San Diego, Ca
Main British Car:
1966 MGB Roadster 350 LT1 Chevy
Jim Stabe's wide body LT1 powered MGB
Posted by: Jim Stabe
Date: February 28, 2009 11:16AM
Owner: Jim Stabe
City: San Diego
Car Model: 1966 MGB Roadster
Part 2 continues here [forum.britishv8.org]
Part 3 is here [forum.britishv8.org]
Part 4 is here [forum.britishv8.org]
Part 5 is here [forum.britishv8.org]
Engine: 1995 Camaro Z28 LT1 with Advanced Induction ported heads and cam (230/234 .576 lift), 10.9:1 compression, Comp Cams roller rockers, 54 mm throttle body and 30 lb injectors. LATEST CHANGE - adding a Vortech supercharger (8 psi) water/alcohol injection and 60 lb injectors. With the blower and a change in cam to a milder grind (220/230) it made 466 rwhp and 479 rwtq (approx. 535 fwhp and 550 fwtq)
Cooling: 19" x 31" two row Griffin aluminum radiator with dual fan unit from 4th gen Camaro
Exhaust: Block hugger headers with 2 1/2" pipes joining into a 3" pipe behind the transmission. Dynomax 3" muffler mounted crosswise at the rear of the car (different than pictures show)
Transmission: T56 6 speed from the Camaro
Rear Axle: C4 Corvette Posi with 3.73 posi (originally was a Dana 36 but swapped for a Dana 44)
Front Susp.: C4 Corvette with QA1 coilovers
Rear Susp.: C4 Corvette with QA1 coilovers
(master) Wilwood balance bar setup
(front) 13" C4 Corvette rotors and calipers
(rear) 12" C4 Corvette rotors and calipers
Wheels/Tires: 17 x 9 1/2" front, 17 x 11 rear Corvette ZR1 wheels. Tires will probably be either Kuhmo Victoracer or Nitto NT05 275-40-17 front and 315-35-17 rear.
Body Mods: Too many to mention but the biggies are: cut down the center and widened 11" and complete tube frame integrated with unibody. There is less than 250 lbs of MG metal left in the car.
Interior: Hand made dash with 5" and 2 5/8" Autometer gauges, Corvette C-4 seats
Electrical: From scratch with a Painless chassis harness and much modified LT1 fuel injection harness for the engine.
This is the latest version of my project that I have been working on since 2001. I've owned the car since I got out of the Navy in 1971. It is a 1966 model and the first thing I did back then was put a 215 Buick all aluminum V8 in it with a Muncie and a Jag independent rear end. The engine eventually got changed for a 215 Olds Jetfire that was turbocharged.
The car was featured in the original Hot Rod Magazine Engine Swapping Guide.
I drove it for about 10 years and had a mishap that crunched the front. I didn't have a good place to work on it then and I sold the drivetrain and just kept the body. The car sat until 2001 when I decided to redo the car using C4 Corvette suspension and an LT1 engine and 6 speed trans from a Z28 Camaro. The last time I narrowed the jag rear slightly to fit under the MG fenders, this time I widened the car (11") to fit over the stock width Corvette suspension. I made a flat, level table to build the car on with rails made from pallet rack beams and four big chunks of concrete. There are also rails that allowed the body halves to be slid apart to see how wide the body needed to be. I had originally planned to use the Corvette front crossmember but it was so ugly that I decided to make a better looking frame and incorporate the pickup points in it. I was able to get a diagram from a frame straightener that gave coordinates for all the pickup points relative to the centerline of the car and to the ground. The suspension was hung in the proper position with fixtures and the frame tubing was built to join all the components. I then had to join the frame into the monocoque but there was no solid place to do it so the framework had to be extended back into the car. I used the backbone concept that Colin Chapman used in the Lotus Elan to get strength into the structure and tie the front and rear suspensions together. The further I went, the less MGB monocoque was left. Now, there is less than 250 lbs of original MG steel left in the car - I have fabricated everything. It has a steel tube frame that is welded into what is left of the original monocoque.
When I get done it should weigh somewhere around 2,300 lbs and the engine should produce somewhere around 425 hp. A 500 hp Viper has a power to weight ratio of 6.8:1, this should be 5.4:1. (Edit: Have since acquired a Vortech blower kit that will raise the horsepower to 500+ and give a power to weight ratio of around 4.6:1).
The steering column and shaft are from a Fiero
The tunnel is sheeted on both sides of the tubing and filled with 1" board insulation between to keep out the heat. The insulation continues clear to the firewall.
I made a 15 gal gas tank that allows for a trunk and clears the exhaust. It has a 250 lpm internal pump. The square hole is a passage for the fuel lines.
I made a rotisserie so I can work on everything without having to get on the floor - getting too old for that! It uses worm gear winch from Harbor Freight and it will pick up the car from the floor and raise it to working height so I can spin it.
I got a kit from Keisler to relocate the shifter forward on the T56 6 speed to avoid having the Cobra style bent shifter. I had to disassemble the entire 6 speed to install the kit - quite a task!
Working on the dash, it will have Autometer 5" and 2 5/8" gauges. The 1" tubing was bent to form an edge for the cowl to replace the padded piece on the stock MG. I had to make a ring roller to form the piece with the gradual two plane bend.
The bumpers were a challenge. Made them up from 2 sets of stock bumpers and a lot of welding, pie cuts and gringing. I made the attachments hidden while I was at it.
Here is the car as it is today. Need to get busy building fenders and lower valances and the like. I built an English wheel to help with the sheet metal construction.
8/23/2010 I wanted a more finished look for the tops of the doors since there will be no windows or windwings so I continued the 1" round tube that I replaced the crash pad with around the tops of the doors and then across the back behind the roll bar. This extends the distance from the trunk lid to the rear of the cockpit by about 7" and gives me a place to stuff a jacket out of the wind.
I didn't like the way the body rolled under at the rockers so I added some panels to give it a beefier look and to blend into the flares better. The front is angled out about 1/2" and the fender will be cut off and attached to the top. The rear angles out about an inch and just covers the tread. Flares will start at the rear of the door.
The throttle linkage took some thinking. I used a universal pedal I got at the swapmeet for the spline and then extended the shaft so it would reach through the footwell (it is 1" thick due to the double wall and insulation). I built a bearing using 2 oilite bushings and some scrap tubing. The cable is a custom unit made by Control Cables Inc in Santa Fe Springs. Works really slick.
I started on the rear fenders. The top section is 3 pieces formed on the English wheel and welded together. With the top cleecoed in place I used a laser line (like the ones you hang pictures with to get them level) to line up the bend line with the line on the door. The outward bend for the body line was done with a tipping wheel in my English wheel. The downward bend was done with flat pliers and finished with square faced hammer and a stepped dolly I made. The lower panels were done in 2 pieces. The rear one was welded into the top section and around the tail light and then the flange was spot welded to the inner fender. The flare didn't look right ending at the door edge. The door has a slight inward curvature at the rear and with the flare curving inward as well, it looked like the side of the car was pushed in at the rear of the door. I had to extend the flare about 12" into the door to make it look right. I am going to push it out the same way I did the door jamb by making a vertical cut in the end and a cut going forward just below the body line. The top and bottom will then swing out to match up with the fender and the gaps filled up with metal and welded. Now all I have to do is match it on the other side in mirror image. I now know why guys build motorcycles - you don't have to make matching parts! More pictures soon
Here are the cuts made to extend the flare into the door. A vertical cut was made in the jamb portion and a horizontal cut was made just below the beltline. The pieces were spread apart until the contours matched up. The line now flows well. I will fill all the wedge shaped openings this afternoon.
I just finished redoing the exhaust system for my MGB project. I previously had a dual system with C5 Corvette mufflers (they fit into the recesses in the fuel tank) but the pipes hung down too low where they passed under the rear end and the tips stuck too far out in back and didn't look right (see pictures above). I decided to tuck the entire exhaust system up into the tunnel so I could have the car very low and still have good ground clearance. I was successful except for two areas that stick down less than 1/2" below the plane of the pinch welds. The car will sit 6 1/2" off the ground at the pinch weld in the back and 6" in the front so I will have 5 1/2" minimum clearance and that is as good as a stock early model car. With the car being 11" wider it really looks low when on the ground. When I finish making the other rear fender I will set it on the wheels and take some pictures.
The muffler is a Flowmaster 50 series with 3" in & out. The engine has block hugger headers that feed into 2 1/2" pipes which Y together at the rear of the transmission into 3" tubing back to the muffler. This is an LS1 powered BMW that has an almost identical exhaust system [vorshlag.smugmug.com] I think it sounds pretty nice. The lowest point of the system is where it has to go under the clutch release lever housing. I made some low profile ovalized pipe from 1 1/4" tube split down the middle and 16 ga sheet welded in between so that the cross section area is slightly greater than the area of a 2 1/2" tube. I did the same thing at the rear where the pipe goes under the rear end. I split two 90* 1 3/4" bends and filled them in with enough sheet to increase the volume to 140% of a 3" tube to create a resonator effect, turn the corner and tuck the pipe up.
The pipes tuck up into the tunnel nicely and don't hang down
The front and rear pipe sections are joined together with a 3" stack clamp from a tractor supply. $30 is better than the $80 that the hot rod parts guys charge. It's not as pretty but it doesn't really show.
I had to make a cover for the muffler since it stuck up into the trunk
Here's the car sitting on the ground, both rear fenders done
This photo shows the ground clearance with the exhaust system in place. It has a minimum of 5 1/2" and this is better than a stock MGB has to the exhaust pipes. The pictures don't really show how low the car really looks standing next to it.
The next step is to make the rear valance below the bumper. When I get that completed I can remove the exhaust and take the engine and trans out so I can get serious on finishing the bodywork. I have decided to make a hood from scratch rather than try to piece the two halves together. I found a 5'x5' sheet of 16 ga aluminum which was needed because the hood is now more than 48" in both length and width. I plan to make a square tube frame out of steel and rivet the skin to it after it is formed. The steel frame may make it a couple pounds heavier but it should add a lot of rigidity and give me strong attachments for hinges and latches.
That's it for 2010, Happy New Year everyone
Got a slow start for 2011 and just finished making the rear pan. I haven't formed the lip around the bottom or around the exhaust exit yet, I'll wait until I have the engine and exhaust out and have it back on the rotisserie so I can get at it better. I am really ticked about the chrome on the rear bumper. I didn't unwrap the rear after I got them chromed, I was just expecting it to have the same quality of work as the front. Unfortunately, the rear has waves and pits in it, not what I expected from a supposedly show chrome job. It has been 4 years since I had it done and they won't do anything about it. The Bumper Shop In Los Angeles - STAY FAR FAR AWAY!!!
2/9/11 (I'm going to start dating my posts)
I finished up the trunk floor tonight. The outer pieces are formed with flanges on the edge so they can be spot welded in. I bead rolled a depression that is close to what I remember the stock pieces looked like, not that it matters much at this point.
I'm going to remove the engine and trans this weekend and start hanging the front fenders. They won't attach at the bottom like the stock ones because of the rocker extensions I put in so I'll have to come up with a mounting scheme.
Ordinarily I wouldn't post after a day like today because I really didn't change the car at all. It started about 7:00 am by getting the cherry picker down from the mezzanine along with the engine stand and getting them both set up. I have a trap door in the floor and a HF electric hoist so it is a little bit easier especially since I have no help. With that done I set about removing the exhaust and disconnecting anything that was connected. Fortunately, there isn't much at this point. I got the engine and trans out, removed the trans, clutch and flywheel and put the engine on the stand. I wanted the car turned around in the garage so I made at least 50 back-and-forths to get it facing the other way. It is up on stands now so I can work on the front fenders, radiator shrouding and spoiler sheetmetal.
Doesn't sound like much as I'm typing it out but I'm tired and sore and I want a drink! Like the Stones said "What a drag it is getting old"! It's my birthday tomorrow so I'm going to relax and recuperate.
I made some new inner door skins a while back because the dash extensions that wrapped around into the door had nothing to attach to since there was a hollow in that area. I had also cut the doors earlier for a chassis stiffening bar that I subsequently decided not to use and I needed to repair that as well. I've been putting off the job of making dimple dies for the holes. The holes were punched with a hydraulic sheetmetal punch set I got from Harbor freight. The set comes with dies for up to 2" but they are for conduit and cut holes to allow a 2" pipe to go through (2 3/8"). The also sell a 3" punch that cuts a 3 1/2" hole. This is the 3" punch [www.harborfreight.com] and this is the hydraulic punch set [www.harborfreight.com] . Both were on sale and I used 20% coupons for both so I have about $70 in the whole setup. One of the best buys I've made from HF. I was able to punch both 18 ga panels at once using the 3" die set and it went through it like butter leaving only a slight burr that cleaned up with sandpaper (but not before cutting my finger).
I spent the afternoon on the lathe yesterday making dies to dimple the edge of the holes to make the panels look better and to also strengthen them. More work than I thought but the panels came out nice so I guess it was worth it.
Punch dies are on top and the dimple dies on the bottom
I only have one picture left on this journal but I will be starting another one to continue with the project, Curtis was kind enough to allow me to bend the rules and do it. So how do you think the car would look painted this color (Ferrari Rossa Red)?
Thanks for following the project, it's nice to know so many people are interested.
Part 2 continues here [forum.britishv8.org]
Part 3 is here [forum.britishv8.org]
Edited 36 time(s). Last edit at 05/04/2017 04:40PM by Jim Stabe.