San Diego, Ca
Main British Car:
1966 MGB Roadster 350 LT1 Chevy
Jim Stabe's Wide Body LT1 Powered MGB "Part 5"
Posted by: Jim Stabe
Date: October 06, 2014 02:03PM
Link to part 1 [forum.britishv8.org]
Link to part 2 [forum.britishv8.org]
Link to Part 3 [forum.britishv8.org]
Link to Part 4 [forum.britishv8.org]
I haven't been able to confirm it with Curtis but I believe I have reached a word or character limit on Part 4 since I got an error message to that effect when I tried to post this message - and so Part 5 begins...
I have decided to take a different approach to making a hood skin. I have a frame and hinge system made but after two failed attempts at making a skin from scratch, I have decided to sacrifice two slightly damaged aluminum MGB hoods to make one. One of the hoods had a damaged internal structure in the hinge area, probably caused by the hood being blown open at some point. The second hood had damage in the left front corner that had been poorly repaired at some point. I removed the inner structure from both hoods and then cut both skins down the middle. I will use the front 3" of one hood and the entire rear of the other. One of the issues I have to deal with is that the curvature of the front of the new hood extends forward about 3/4" - 1" further than a stock hood does so that the curve flows soothly with the extra width. That is the reason I have to use the front 3" of one hood so that it will follow the revised contour of the frame. The rear edge is slightly off also but I can adjust the edge of the 90* fold si it fits the contour.
It will still require me to make a center strip but that is relatively easy since there is very little curvature side to side. I recognize my shortcomings welding thin aluminum so all welding will be done by a coachbuilder I met and I will actually have to pay for some labor on the car. He is a master at gas welding aluminum sheet and actually built an entire aluminum body for a wrecked Dino Ferrari. The guy's shop is in Irvine about 90 miles up the road and it will require at least two trips and possibly three to get the job complete but I should have a nice hood at the end of it all.
I also didn't like the look of the Camaro mirrors I had on the cat - thought it screamed Mid 80"s GM too much. I ended up buying a pair of mirrors for a 356 Porsche that look more appropriate to the car. [www.ebay.com]
I may only use one on the driver's side since I never needed the passenger side one when I had the Camaro mirrors on the car.
Here is a picture of the drivers's side mirror on the car. I also installed a fire extinguisher after I saw a picture of a car on the news that burned to the ground on the side of the freeway.
I haven't driven the car for a couple weeks so I may take it out and scare myself again - damn the car is quick.
Having driven the car a bit now both on the streets and on the freeway, I find that I would like it to idle a bit better and have a little crisper off idle performance on the street. On the freeway, it runs fine in 6th gear as long as you are going 70 mph (1700 rpm) or more but if I have to slow down to 60-65 mph (1400-1500 rpm) the engine isn't happy and it starts to "catch" at about 60 mph. Downshifting into 5th is not good either because of the wide spacing between the 5th and 6th ratios - besides it's a pain everytime you have to slow down a little. I talked with the techies at Comp Cams and they recommended a cam with about 10* less intake duration at .050" and a wider lobe separation angle of 114*. This should raise my idle vacuum from 10 inches to 15-16 inches and make it more responsive. for street driving. It may cost me a few hp at the top end but I have plenty to spare so that shouldn't be an issue and it should be easier to manage in autocrosses. I could probably do the cam change in a day but I'm going to allot 2 days just so my back doesn't end up killing me. I have to order the cam so I could possibly have the hood done by the time I get it.
Here is an update on the hood. Because the front of my frame extends about 3/8" further forward than the stock hood due to making the curvature of the front edge flow smoothly across the widened section, the front pieces were cocked slightly. I overlapped the front and rear pieces and scribed a cut line on the front section. Once cut there was a perfect butt joint for welding. I didn't have a good center piece for the front so I used the center of the under bracing structure and formed the rear portion to match the contour of the hood. The last picture shows half of the bracing structure piece and how it flattens out to form the mount for the latch. The finish on the center piece isn't perfect but that's why they invented Bondo. I had to make the rear center section from 3003 sheet but the contours weren't too bad and I got a pretty good fit. I used the same scribing method to cut the side sections of the stock hood pieces to fit.
I had a guy all lined up to do the welding, he is a very talented coach builder who learned his trade repairing exotic race and street cars. He had quoted me a very reasonable price during the first two visits but when I took it up yesterday to get the work done, the price had risen to $1500. All he talked about was how rough the business had gotten and his recent divorce. Needless to say I gathered up my stuff and left. This may be a blessing in disguise as it now forces me to learn how to gas weld aluminum. I was planning to learn the skill anyway but this forces the issue. Also probably means I won't have a hood as soon as I planned. If the welding attempt fails I will probably talk with Dave Craddock and get some tips on building a fiberglass one.
Well, I stepped for the welding goggles, flux and filler wire to the tune of $270 so now I just have to practice. I have to give a shout out to Sam Terracina in Arizona for donating an aluminum hood that he has to the cause. It was an extra that has a dent in the very front and all I have to do is meet him in Yuma to pick it up. I'll be making the trip on Monday morning.
Meanwhile I have been working to install the cam which required removal of almost everything on the front of the car. Seems like everything I needed to remove required taking something else off. To remove the air inlet ducting required removing the front bumper to access the screws that hold it down in the front. To remove the water pump I had to take off the blower because one of the bolts was covered up by one of the idler pulleys and the only way to take the idler pulley out was to take the blower off. It goes on and on. Another thing I discovered is that I hadn't provided a good way to drain the cooling system and it holds 5 gallons of coolant. I bought the largest plastic pan I could find at Walmart and removed the block drain plugs which made an absolute mess in the garage but I was able to capture most of the coolant. I siphoned the radiator out through the top radiator inlet so that wasn't too bad. Lesson learned - I'm putting 45* fittings in the block drains with petcocks and adding a short length of hose to the radiator drain (which I had plugged because I couldn't get to it) with another petcock so I don't do through this again. Here is the pile of stuff I had to remove.
All to get down to this
While I have it apart I'll bend up a 7/8" sway bar and mount it since it is much easier to work with all the stuff removed. I also asked on some other forums why the power and torque were coming so early and then falling off quickly (max power was at 4800 rpm). A couple knowledgeable people thought I may have an exhaust restriction and I should look at some other muffler than a Flowmaster. Doing a little research I found that a 50 series Flowmaster like I have only flows 53% of what an open pipe flows whereas a Dynomax Ultra flow flows 100% of what an open pipe flows. The Dynomax was also just as quite as the Flowmaster and didn't resonate as badly around 2000 rpm. The test was run with 2 1/2" mufflers but I believe the same would apply to a 3" like I have. I'll be replacing the muffler before I take it back to the dyno to have the tune tweaked.
Probably won't get it back on the road until after the holidays but that should give some time to practice welding.
I ordered some 7/8" 1144 stressproof steel for the front sway bar. I used that material rather than 4340 because I don't have to heat treat this material to get the properties if I bend it cold. I made up some tooling for my HF 20 ton press. The ram piece is a 3" diameter steel bar with a V groove turned into it and then cut in half. I welded a piece of 1 3/4" x 1/8" wall tube to it so it would fit over the 1 1/2" diameter ram on the press. The lower rollers are 1 1/2" aluminum bar with V grooves riding on 3/4" grade 8 bolts. One of the rollers actually rolled but the other one just wore a spot in the aluminum. It didn't mark the bar in either case so I guess it doesn't matter. I practiced on an old 1" diameter sway bar that I had to see where the bends actually came out in relation to the marks I made on the bar so that I would end up with the proper amount of straight section between the mounting blocks. After a few adjustments to the marks I had made on the bar I started bending the 7/8" 1144.
The first two bends came out exactly where I wanted them to be so I bent up a piece of aluminum welding rod as a pattern to get the location of the return bend at the ends of the bar. You can see it in the photos of the bar laying on the ground.
To bend the returns I had to tilt the press to give enough clearance that the other end of the bar didn't hit the floor, a 4x4 and a 2x4 under the front legs did the trick. Now I have to make the links to connect it to the lower A arms.
I have a friend coming over tomorrow to help put the intake manifold back on and then I can put the rest of the front end back together.
I had a friend remind me that I needed to update the progress so here goes. I made the swaybar links. They are a combination of the Corvette lower piece with a plate welded in, a short aluminum spacer and a clamp type bracket on the bar with ears to accept the heim joint.
The links required me to fix some of the earlier screw-ups I had made. I thought I had done a good enough job of guesstimating the alignment settings when I was welding in the brackets for attaching the A arms and coilovers to the frame members. I was mistaken, the upper A arms had to be swung to the rear a considerable amount to gain the necessary caster. This caused the front leg of the upper A arm to interfere with the coil spring on the coilover. I was able to initially fix it by inverting the QA1 shocks so the spring was now below the A arm. Now that I have the sway bar in place the spring now interfered with the sway bar links. I had to cut off the upper shock mounts and move them rearward so that the coil spring will be centered between at arms when mounted in the conventional manner ( there is equal clearance between the spring and the front and rear arms although it doesn't look like it in the picture). I've made the new mounts removable this time in case I need to change them again for some reason. You can see where the original mounts were and that the new position is about 3/4" further back.
Moving the upper ball joint rearward and increasing the caster also caused the edge of the tire to slightly rub the front of the foot well. I now have to cut out that sheetmetal and move everything back about 3/4" for proper clearance - not what I wanted to do after everything was painted. You can see the marks from the tire rubbing at full lock.
To change the cam I had to drop the front of the pan to be able to remove the timing cover. I wanted to take the pan off to see if there were any nasty shiny bits of bearing in the bottom so I tried removing it only to find I couldn't get it to go past the oil pump pickup. When the engine was on the stand I was able to get the oil pan on and off by wiggling and tilting the pan to get the oil pickup past the internal baffling of the race pan. In the car I didn't have the same range of motion of the pan because of the transmission and exhaust. It took me a full day but I eventually got it off. I modified the baffling so that I can now pull the pan straight down to get it out of the car.
I have been curious ever since I got the car tuned why the power came in at such a low rpm (4800) and then dropped off. A couple guys on the Corvette forum in the forced induction section may have hit on the answer. They pointed me to a muffler test that compared flow rates to an open pipe. The Flowmaster I have only flowed 53% of what an open pipe flowed but a Dynomax Ultraflow was 101% of open pipe flow. Oddly enough, the Ultraflow was also several db's quieter than the Flowmaster throughout the rpm range. Guess what I have that will be installed before I have the car retuned. It will be interesting to see what the power curve looks like with the new muffler.
Started it up today and everything looks great so far, it idled at 16" of vacuum instead of 10" and it was a lot smoother even before it gets retuned. The exhaust sounds really nice with the Dynomax Ultraflow and may be slightly quieter than the Flowmaster even though it is a straight through 3" core muffler. I had a broken bearing on one of the coilovers so I won't give it a test drive until I get the replacement on, hope it comes today. I'm anxious to see what the freeway manners are like with the new cam.
The replacement bearing for the coilover came in today so I was able to take the car out for a short drive. It idles much smoother at 800 rpm with 16" of vacuum, it pulls nicely from under 1500 rpm in the higher gears and the exhaust note is quieter and more pleasing to the ear than it was with the Flowmaster. I still have to get it retuned so I didn't give a full throttle test but it is much more of a pleasure to drive now.
I have an appointment to get the car retuned next week but I decided to use the time for a peace of mind addition to the drivetrain. The driveshaft is very stout and it uses the best U joints so I'm not expecting a failure. However, the fuel and brake lines run through the tunnel and I want to protect them in the unlikely event that the driveshaft does fail. I made the actual containment ring from 1/4" wall steel tubing and then split it in half so I can get it in the car without taking out the driveshaft, The two halves are held together with 3/8" grade 8 bolts like a connecting rod big end. I also made it fairly close fitting to the driveshaft tube so it can't flail around if it does break. It should be OK since I have stiff polyurethane engine and trans mounts that allow very little movement of the drivetrain..
Here a the similar one I made for the back end of the driveshaft
Stay tuned for the dyno results. I also ordered the 5/8" master cylinders to reduce the pedal effort required for a hard stop. Need to start practicing gas welding aluminum sheet so I can get the hood done.
Got the car back from the dyno. The old cam made massive torque (543 ft lbs at the rear wheels) and the horsepower was 450 but at only 4800 and then it dropped off rapidly. With the smaller cam you would expect the horsepower be lower and to peak at a lower rpm but it actually raised the peak almost 1000 rpm peaking at 466 rear wheel hp at 5750 rpm (that's 536 flywheel hp). What a difference a muffler makes!
Before the horsepower and torque peaks, the new curves were flatter and lower as I expected but it still makes over 300 ft lbs at 2500 rpm and 425 ft lbs at 3000 rpm and it stays over 400 ft lbs past 6000 rpm (peak is 479 ft lbs at 4300 rpm). All the new numbers were with the water/methanol injection turned off and the old ones were with it turned on so they will probably be closer with the system on. So am I disappointed with the lower performance now? It still has plenty of power to scare me and I still need to be sure to have it pointed straight ahead when the boost comes on. What is nicer is the normal driving and I think it will be much easier to control in autocrosses, I just need to control the acceleration rate by shifting early.
I am going to keep the old cam because if I build another engine with forged internals ( I have a stock shortblock with cast pistons and 11:1 compression now) I would love to see what it would do with the less restrictive Dynomax exhaust. My guess is well over 500 rwhp and close to 600 rwtq and I could regain some of the low end performance with a set of Rhoads lifters [www.rhoadslifters.com] The engine just won't take that kind of hp now.
I turned 70 today. Happy Birthday to me. To celebrate I took the 536 horses out for some exercise and then the wife and I went wine tasting in the afternoon.
I had the flu for a couple weeks so didn't get much done on the car. I did manage to make a new mount for the dash rearview mirror. I never liked the mount it came with because it was just a piece of square stock and it didn't get the mirror high enough to see entirely over the rear deck. I machined, filed and sanded it out of a piece of 1"x2" aluminum stock and I will have it chromed when I do the rest of the chrome on the car. It positions the mirror about 1" higher and the angle matches the layback of the windshield. I won't be able to mount it until I take the windshield off to make a new glass for it.
I also decided to use the gen 1 RX7 door mirrors because their angles are a good compliment to the windshield post angles, they have a clean look and they are the right size for the car. They will be painted body color. I'll take a picture when I get them on the car
Yesterday I finally put in the 5/8" master cylinders for the brakes. I originally built the car with 3/4" masters but the pedal effort was too heavy in a hard stop. The 5/8" ones are perfect - around town braking is much easier now (not power brake easy but a nice feel) and the car really stops when you push on them hard. It is just the feel I was after. The tires I have on the car now are way past their date codes and so probably won't provide optimal stopping distances but I will test it anyway when I get a chance. I would love it if it stopped from 60 mph in around 100', I think that is about what the new Z06 Corvette does.
I'm practicing my aluminum welding and so far I have been able to make a 3" long weld that holds together well - looks, not so much. Keep practicing.
I have been practicing my gas welding for aluminum and have made some progress, still a long way from being ready to weld up the hood though. On Monday the oxygen regulator on my welding setup died so that put an end to my practice until the new one arrives. I found a low pressure regulator that should work much better for welding aluminum. You need very low pressures, like 2 psi and the regulator I had had a pressure range from 0 to 200 psi so trying to set 2 psi was a problem. The new one has a range from 0 to 30 psi and there are widely spaced 1 psi graduations so it should work much better.
While I was down I decided to mount the RX7 mirrors. I'm really happy with them - they are very rigidly mounted so no shake and the mounting arm is the perfect angle to match the angle of the windshield posts and they aren't too large for the car. They should look really nice painted body color. They are electric mirrors but I couldn't get them to work so I'm not going to hook them up. Rob Ficalora used Chrysler Crossfire mirrors on his car and has never hooked them up and he says he has never had to reset them.
Many of you know Lloyd Faust from the other site. Lloyd called me a while back and said that the lower corners of the wheel openings bothered him. Too squared off he said with the rest of the body being very curvy. I had played around with a black marker to see if I would like it and so yesterday out came the die grinder with cutoff wheel and the recip saw. All had to have return flanges and/or cap plates welded on so it took me most of the day. After all is said and done I think he was right. The 1st picture is what they looked like before and the 2nd is what they look like now. Small change but I think it makes a difference in the looks of the car. You can also see the RX7 mirrors mounted on the car, the angle of the stalk is almost a perfect match to the slope of the windshield posts.
I have not been happy with the shape of the top part of the rear wheel openings. I feel the slightly flattened top is a distinct styling cue for the MGB and I wanted to retain it in the new fenders I built. However, I got the shape wrong and the flat on the top was too pronounced and the radii of the top corners was too sharp, it just didn't look right. One of the reasons I left the opening wider at the top was because I was afraid that the massive rear wheel/tire might not come out without disconnecting the suspension.
I decided to change the shape to match the stock MGB so I took a tracing of the opening off a friends car so I could duplicate it. I got some 5/16" square rod today to form the edge of the new opening. It took quite a bit of fiddling because they have to bend in two planes to stay even with the fender sheetmetal but I finally got them tacked in place. It took about an hour and a half to form the pieces of rod and get them ground down so they would blend into the edge of the existing opening. Ta - Da !! I can get the wheel/tire on and off the car with the reshaped wheel openings. There is slightly less room for the tire to go in and out but it still has plenty of clearance. Need to get the other side done and both welded permanently and then I can fill in the gaps with new sheetmetal. Quite a difference in the shapes of the two openings.
I made a form from a scrap of MDF to use as a pattern for bending
Here's what it looks like with the gaps filled in with sheet metal.
One last bit of surgery on the car before I get back to practicing welding for the hood. In the early stages of construction I estimated how much clearance I would need behind the tire to clear the front of the footwells at full steering lock. Well, I guessed wrong and the outside edge of the tread just touched the rear of the wheel well/front of the footwell. I had to provide clearance so I notched the 1"x3" tube that forms the bottom and then cut out the sheetmetal above and filled in with new metal. The tire now has enough clearance that I can fit my fingers in the gap at full lock.
I haven't fallen off the edge of the earth, I just haven't had time to work on the car in the past 2 weeks. My daughter wanted an outdoor table for her patio so I decided to make her one for Mother's Day. It is her 1st Mother's day since giving birth to our grandson. It was more of a project than I thought and has taken all my time for the past 2 weeks, turned out nice though. Here is a picture before the finish gets applied.
Going to get back to aluminum welding practice tomorrow so I can get the hood done.
Well, I practiced and practiced gas welding aluminum and I am just not confident enough to try welding the hood together. So I did the next best thing and am TIGing it together. I'm not much better with a TIG but at least I can get the pieces stuck together and grind/file the extra weld away. You can see how well all the panels fit together from the pictures at the beginning of Part 5, that is how well they fit before I started welding. I tacked the long seam on the passenger side first and then tacked in between the tacks until I just had 1/2" - 3/4" between them. I welded the front half of the seam solid and then reshaped the area with hammer and dolly and English wheel. The shape of the passenger side is pretty close but you can see what it did to the edge on the driver's side.
My friend Mike came over to help get the driver's side seam tacked and having an extra set of hands was invaluable. The edges lined up fairly well at the back so we started there. I would do a tack out about 3" and then go back and align the edges between the tacks and tack it again halfway in between. This worked pretty well for the first 2' and then the gap between the sheets started to get wider.
We stopped and a little slapper / hammer and dolly got the shape close to where it should be and started to close the gap at the front slightly. It wasn't enough so I took off the aluminum skin and ground the edge of the steel frame slightly to allow the hood section on the driver's side to come closer to the center piece. A couple tries and the gap was nice and tight again but the center strip had to be man-handled to get the edges to line up. That's where Mike's extra hands came in and we were able to get it tacked about 3" at a time before I had to hammer and dolly the shape again. Each cycle of tacking and shaping caused the seam to get closer and closer until the final 8" the edges were perfectly aligned
The two front pieces on the driver's side were tacked in place and it was starting to look like a hood.
The fit of the hood to the fenders when closed is pretty good without making any adjustments ( I just had to see what it looked like)
I still have to weld in the center nose piece and finish weld the seams that are just tacked. When I get all the finished welds dressed I can tune up the shape and finish the contours in the English wheel. I will epoxy prime and paint the underside of the skin before I crimp it on to the frame. I can then adjust the edges so the skin is level with the fenders and cowl. Once that is done I can block it out and paint the outside.
I feel like a big weight has been lifted from my shoulders knowing I will have an aluminum hood on the car.
Here are a couple of pictures of the completed hood skin on the frame installed on the car. I still need to repaint the frame, install some underhood insulation and crimp the skin to the frame
Here is a picture of the insulation installed on the underside of the skin. I used Bonded Logic material that I got from Summit Racing, it's light weight (3 oz / sq ft), durable and comes in a 4' x 6' sheet. Used some aluminum tape from Ebay to seal the edges. The stuff is cheap - only $25 for the 4 ' x 6' sheet.
I got the skin crimped on to the frame and added a center support for the insulation to help keep it in place. The support is a piece of aluminum sheet with dimpled holes riveted to the frame. Here is a picture of it on the car.
I need to spend some time getting it to fit right but it's nice seeing it on the car.
The fuel level gauge has been sticking so I pulled it out to see what was happening. When I looked down in the hole I was shocked to see the tank sealer I used peeling off the walls of the tank in sheets. I fabricated the fuel tank for my car from aluminum several years ago and I pressure tested it at the time and it held 5 psi overnight. When I finally put gas in it last year I found a couple pin hole leaks and I also had concern that the alcohol in the gas might attack the aluminum. The Hirsch sealer had some good reviews so I bought the kit to both seal the leaks and coat the inside with an alcohol proof barrier coating. [www.hirschauto.com] . I followed the instructions to the letter etching the interior with the material supplied in the kit. I took extra care to make sure the inside was completely dry (per instructions) and actually ran the heated air through the tank twice as long as specified. Next came the actual sealing solution which got thoroughly sloshed around and the excess drained. I allowed the material to cure several times longer than the instructions called for and when I filled the tank, the leaks were no more.
Fast forward a year to this week. The old sender was a swing arm type and I think it was getting hung up in the peeling coating. I was afraid that the peeling material could clog the fuel pump ( I have an in-tank pump for F.I.) so I removed the tank and pulled out the pump and filler neck as well. Good thing I did because the sock over the inlet was covered with pieces of the shed coating. Spent the whole day scouring the inside of the tank where I could reach (I put 4 baffles in it). I called Hirsch and they told me that their instructions say that it does not adhere well to new metal (isn't that what the etch is supposed to do?). I reread all their literature and there is absolutely no mention of adhesion problems on new metal (I wouldn't have bought it if that were the case). I emailed them pointing out their oversight and am still waiting for a reply. From all the online reviews of users sealing rusty tanks I have to believe it is a good product for that application but I strongly advise against using it on a fabricated tank. The picture shows what I have removed from the tank so far. I will have to pull the fuel pump periodically to see if the inlet sock is getting contaminated with shedding coating - hopefully, it won't. The last thing I need is to have the pump starve and the engine go lean when making boost.
To be able to get my hand down into the end of the tank where the sender is I had to cut out a larger opening which will be covered with an aluminum plate. I also got a new sender that is a straight tube design rather than the swing arm - I checked it by flipping it upside down and it read full, right side up it reads empty just like it is supposed to.
If you are thinking of sealing your fuel tank, I do not recommend using the Hirsch product.
My old friend Lloyd (you may know him from the MGE) strongly suggested I fix the area below the tail lights before I start on the body and paint work. Lloyd has been spot on with his design suggestions throughout the project and I think he did it again with this one. There is a void below the bumper before you get to the rear valence that makes that part of the car look unfinished. It never really bugged me until he brought it up and then it was all I saw when I looked at the back end of the car. People who remove the bumpers and install a Sebring body kit fix the problem with the new valence provided in the kit. This picture shows what the issue is with the stock body, it looks even worse without the bumper in place.
I decided to add a rear fascia similar to the Sebring but do it in steel and still allow the bumper to be used. The fascia is formed from four pieces with the weld seams under the tail lights and in the center. Lots of shot bag and English wheel work to form the pieces and a length of 1/2" tubing to soften the lower edge. The top and bottom pieces are just tacked together now and is still removable from the car. I want to finish weld all the seams and epoxy paint the inside before I weld it on the car for good. I think it improves the look of the car and finishes the rear corners that looked unfinished before.
You can see how much the new valence moves the body line out from the stock valence.
This is what it looks like without and with the bumper in place.
I'll take a picture after it's all welded in place and primed when it is sitting on the ground.
Here is the new rear valence welded on the car and primed. It's one of those things that isn't readily apparent when you walk up to the car but it finishes off the back end pretty well.
Here is a shot with the hood on.
I started on the new roll bar this morning. I want to put a slight curve to the top section to make it match up better with the windshield frame and also because having a straight section that long would look odd. I made a cardboard template to be able to visualize what it would look like and to have a guide for the bending. It actually matches the curvature of the windshield frame very well although if viewed from the front it looks like it has too much curvature
If viewed from the rear it looks too flat
To put the curve in the bar I used a Harbor Freight tubing roll bender but the 2" DOM was too stiff for it to bend. I made some extensions to move the lower dies further apart and I was able to get it to bend but with considerable effort. I also had to replace the cheap Chinese set screws that were supposed to hold the upper die to the shaft as well as the screws that hold the hand wheel to the shaft - all of them bent over and had to be drilled out. There are now some aircraft quality 5/16" allen screws holding everything in place.
The bar has a nice gradual curve and I can get the other bends done at my friend's house.
That is a lot of work! I was able to borrow a JB Squared bender with 2" dies that had been converted to operate with a modified trailer jack so it did not have to be bolted down to the ground. The 2" DOM tubing was difficult to bend and I was glad I didn't have to be pulling on a bar to do it. It did, however require a lot of cranks with a 1/2" ratchet. I'm glad I bought a less expensive piece of welded tube to practice on because I wasn't happy with the side angles and was able to correct it on the real piece. At any rate, after 5 hours cranking on the bender in 90* weather I have a bar that I'm happy with.
The bar is as much for appearance as for actual roll over protection so I kept trimming the legs down until the height looked right with the windshield, it is now about 1/2" higher than the windshield frame and just over the top of my head. I was amazed how much difference 3/4" in height made in the way it looks in the car. The legs bolt into 1/2"-13 threaded tubes that I welded into the frame when I was building the car. There will be a 3rd 1/2" bolt perpendicular to the other two that will bolt it to the lower section of the inner fender well.
If you look closely you will notice the top section of the bar has a slight arc to it, about an inch in the middle. Since my car is 11" wider a bar with a flat top didn't look right with the curve of the deck lid and of the windshield frame. I rolled in the curve with a modified HF tubing roller as shown above. I still have to make the rear supports which land inside the trunk and finish weld everything and get it powdercoated. I am also going to add a removable bar just below the height of the deck to have a mounting point for a harness if I ever need it.
I'm very happy with the way everything fits and the clearance to the body where it exits the cockpit, Pretty pleased for a first effort bending a roll bar.
Here are the rear roll bar supports tacked in place.
I also picked up some weld in clevises today so I can make a removable harness bar
I got the harness bar brackets welded in today and I ordered the belts from Summit. I need to have the belts to figure out where the mounts need to be in the harness bar. I really like the way the bar is removable using the clevises. The harness bar is 1 1/2" .120" wall DOM tubing. I'm going to pay someone to TIG weld the rear stays to the hoop and the clevises to the harness bar tube. I practiced all morning and I just can't reliably make nice looking TIG welds - oh well.
I installed the seat belts. I got 3" G Force racing belts and discovered that there wasn't enough room between the seat and the inner rocker for the belt to fit. I had moved the driver's seat over about 1 1/2" earlier to make it line up with the steering and pedals better but now I had to move it back about 1/2" to provide clearance for the seat belts. I tried moving it to the original position but the offset to the controls was too uncomfortable. The new position isn't perfect but still much better than where it was originally. I had to get the seat where it was going to stay before I weld the shoulder harness attachments to the harness bar, I'm waiting for the weld brackets I ordered to arrive.
I've made a decision about the look of the car that I hope I don't regret. I have seen a number of cars in shows that have a satin nickel finish on the trim rather than chrome and I really like the look. My friend has an Audi A-4 that has the same type of finish on the trim and it looks great. I was never happy with the job the chrome shop did on my bumpers so I was eventually going to have them redone anyway. So what I'm going to do is get everything powdercoated with a satin nickel finish - roll bar, windshield frame, gauge insert, shifter bezel, e brake bezel, headlight and tail light trim, grille and bumpers. I think it will give the car a tough, purposeful look with the red paint. The engine compartment already has that look and I like it.
Like I said, I hope I don't regret it.
With the roll bar done the next item on the list is cutting another windshield to replace the one that cracked. I cut the windshield from a 1967 Impala glass and I bought another one from the same auto glass supplier. When the guy delivered it he got really interested in how I was able to cut the glass - he had tried cutting a windshield using the glass cutter and then burning alcohol to soften the plastic lamination so it could be cut with a razor blade. He broke five windshields before he finally gave up. I gave him a quick demo using the Rotozip with a diamond router bit and he was amazed. He wants me to teach him how to do it. I'm debating whether to teach him or to do subcontract work for him. I would only do it if I was not held responsible for any cracked windshields.
BTW I have redesigned the lower support for the glass to relieve the stress that cracked the first one.
I was going to powder coat the trim on the car but there are a couple problem pieces that may not take the heat required to cure the powder, the rear view mirror for one. I also wanted to slightly contour the face of the grille to make it look more like the stock early MGB piece and the Bondo also would not take the heat. I found a paint color that I like, it is called stainless steel, and it has the look of stainless with a very slight tinge of gold to warm it up a bit. You can't really see the gold tone unless you hold it side by side with a true silver. When I was at SEMA a couple weeks ago I ran across a company called Cera Kote that makes very durable clear coatings that are used a lot in the firearms industry. They make a matte clear coating that is harder than a powder coat finish and it is super easy to apply. All you do is spray a wet coat and follow it immediately with another wet coat and let it air dry. Once set the only way to remove it is to sand or grind it off. It is highly scratch and chip resistant. It is also a non catalyzed product so you can pour the excess right out of the gun back in the can. I was going to get some matte clear urethane but it would have cost me more that the Cera Kote and wouldn't have been as durable.
Here is what the trim color looks like next to the red body color. One is in the direct light reflection and the other at a slight angle off. I think I'll like it.
I have not been running a front license plate on the car because I didn't want to ruin the looks of the clean front bumper but I was talking with a Highway Patrol friend the other day and he said that no front plate is one of the big reasons they have to pull a car over (cause to stop he called it). Since I am going to dechrome the car and paint the bumpers anyway I decided to make an easily removable license plate so I can take it off at a car event and put it back on for the trip home. With the plate removed there are only two small bosses under the bumper and back from the front edge that you have to bend over to see. The extensions off the back of the plate are threaded so all you have to do is put two bolts through the bumper brackets and the plate is back on. After it was all done I don't mind the look of the front plate as much as I thought I would.
I also attached my sand cast gas pedal
Not much progress due to catching up on maintenance around the house. I have started on refinishing the trim in a flat stainless color. Any parts that were chrome (headlight and tail light bezels, bumpers, etc all had to be sanded down and coated with etch primer before I could spray the stainless paint and clear coat over the top. Everything went fine until I got to the bumpers. I scuffed up the front bumper, shot it with etch primer and then with the stainless paint. I was shocked at all the ridges that were in the bumper from the chrome shop grinding and sanding (won't be going back to those guys). Once the surface was shot with a flat paint, all the shadows from the ridges showed up. I thought the chrome surface was pretty nice before I started the process. The paint and primer on the bumper acted like a guide coat revealing a very poorly prepared surface. Amazing how the shiny chrome masked all that, I thought the opposite would be true and the chrome would show the flaws. The pictures below show the back bumper at the start of the sanding process and how all the surface imperfections show up. I had 4-5 hours of block sanding time on the front bumper and it looks like I will have the same amount on the rear. The first picture shows the bad surface. The second shows sanding about 1/2 done and the last is the front bumper painted but without the clearcoat.
It's been a while since I updated. I have been getting ready for shoulder replacement surgery tomorrow by getting a lot of things done around the house that I won't be able to do for a while. As a result, the car has had to sit. I did start on the bodywork at the back end and have the rear valence fairly straight and the panel just below the trunk is coming along also. I was going to finish sanding the Bondo today and spray a coat of primer on but the switch for my air compressor decided to stop working. I'll probably get some rattle can primer to cover it up in a couple weeks so it doesn't absorb moisture and then sand it off when I am able to get back on the project. The doctor says I can get the other shoulder done in 3 months so it will likely be the end of the year before I can finish the bodywork and paint the car. Here is what the back of the car looks like now.
I'll be back when I can use my shoulders again
The shoulder is starting to feel better so I decided to do some painting on the trim, bumpers and roll bar. I Bondo'd the uneven spots in the rear bumper and primed it. I then painted them with the stainless steel spray paint and finished them with a couple coats of flat clear urethane. The look is just what I was after.
I assembled the grille with the GM emblem. I think it turned out well. The mesh is an elongated hexagon pattern in ABS plastic that I bought on Ebay.
I got my seats and console back from the upholsterer this morning and am happy with the results. The material is a matte black vinyl for the console, bolsters and headrest with the same material perforated for the seat bottom and center of the backrest. I got extra material to cover the door and kick panels which I'm going to do myself. I'm going to keep them simple with maybe just a thin strip of metal trim painted the same as the rest of the trim on the car. I'll have the same guy do the carpet after the car gets painted.
Well, it's back under the knife again next week for the right shoulder so there won't be any progress again for a while. At least I should be more coordinated with my left hand after this is over. Wish me luck
I have been looking for several years to find a reasonably priced Dana 44 Corvette rear end to replace the much weaker Dana 36 that I have in the car now. I haven't broken the Dana 36 yet but I have been careful applying the power and I know it is just a matter of time until it breaks. I was looking on Craig's List and noticed a guy selling a 1985 Corvette rolling chassis (no engine or trans) but it did have a Dana 44 rear end AND it already had 3.73 gears installed with a beefed up posi and billet steel bearing caps with only a couple thousand miles since the work was done. The engine developed a knock and he parked it about 5 years ago. He wanted $1000 but I was able to get it for $900 - an used Dana 44 would cost a minimum of $1200 plus an additional $600 - $800 for the gears and posi.. The really good news is that the car is in great shape. I figure I can sell the newly upholstered seats, rear glass, doors, front suspension and wheels/tires for more than I paid for the car.
Today was a good day all in all.
The Corvette is completely apart and all the waste fiberglass has been distributed throughout the neighborhood trash cans and is gone. The steel (mostly the frame) has been cut up and delivered to the scrap metal yard, 680 lbs in all and I got the princely sum of $24.48 for the lot. Best part is I have the driveway back and it doesn't look like Sanford and Son out there now. Without advertising, I have already sold the seats, steering column and front suspension and have recovered nearly half of the investment in the car. I still have lots of valuable pieces left and should have no problem clearing $1500 by the time I'm done and I can still sell my Dana 36 for $350-$400.
Between Thanksgiving and Christmas I will probably only be able to get the new rear end installed. Bodywork and paint will have to wait until after the new year.
Some good news and some not so good news on the Dana 44 rear. I took the batwing off and the gears are, in fact, 3.73 and they appear to be in like new condition. The bearing caps are also billet steel just as the owner said. The bad news is that three of the 5 bolts that mount the batwing were stripped when I went to reassemble and one of them had a poorly installed helicoil. The bolts are metric that are approximately the same size as a SAE 3/8" bolt. I drilled out the offending holes in the pumpkin and tapped them to 1/2"-13 SAE thread so that the threads are in good aluminum. Glad I decided to take it apart, hate to think what 550 ft lbs might have done. I need to let the silicone sealant set up for a couple days before I put the gear lube in so it will be next week before I can install. Hope everyone had a good Thanksgiving.
So I got the rear end back together on the bench and noticed some gear oil. Looking more closely, I saw a crack on the bottom side of the gear case starting where I drilled and tapped a drain plug hole. I have the crack gouged out and hope to get it TIG welded back up this week. Guess I won't be having a drain plug. It could be worse and I could have installed everything in the car before I discovered the crack. Merry Christmas everyone.
I got the housing welded up by a friend of a friend who happens to be a certified welder for aerospace components. He did a great job. As he was heating the casting to clean out the oils from the crack the crack continued to open up so the repair ended up longer than I originally thought. I had to dress the weld bead down on the inside to clear the ring gear, it comes really close to the housing.
After disassembling the rear I also found some questionable assembly issues and a bearing that was a little rough so I decided to get all new bearings and seals and have a pro assemble it. In a way, I'm glad the crack happened because these issues would have been raised down the road. Goes to show you can't always believe what a seller tells you. I also had to shorten the torque arm because the Dana 44 is about an inch longer than the Dana 36 that came out. Just waiting for the gears to be installed so I can get it back in the car.
I FINALLY got the rear end back together and back in the car but not without some challenges along the way. I previously had a polyurethane bushing on the forward end of the torque arm but I was having a hard time getting the hole to align with the chassis after shortening it. Solved the problem by using a 5/8" chrome moly rod end which solved both the length and misalignment issues. The poly bushing was 1 3/4" wide and the rod end is only 5/8" so I had to make up some spacers. I JB welded the 5/8" block to the chassis and the 1/2" block is loose so I can insert it when I put in the bolt. I have the driveshaft out being shortened also
The rear doesn't look significantly different than it did before but the internals are a lot beefier. I learned that the Dana 44 uses two different diameters of ring gear. The C4 Corvette and early Viper used a 216 mm diameter ring gear (8.5") while the later Viper and some Jeeps used a 226 mm ring gear (8.9"). The aftermarket has adopted the 226 mm size as standard so I had to relieve the case in 3 areas to clear the larger diameter. Nice knowing that I have the strength somewhere between an 8.8" Ford and a 9" Ford. I can actually make some hard launches with the car now without worrying about scattering the rear end. I have also sold some more of the Corvette parts so the entire rear end conversion has been paid for including the new bearings and seals, setup and shortening the driveshaft. I also sold my old rear end so I have some in the kitty as well.
We are getting some clear weather so I'll be getting back to the body work so I can get the car painted. I would like to take it to the gathering in June since it is in San Diego.
Edited 70 time(s). Last edit at 02/08/2017 08:02PM by Jim Stabe.