MG Sports Cars

Yeah, the cylinder looks good too. Probably could have kept on going if that lifter valley cover hadn't blown wide open.

Jim

Just for the record, I NEVER drove this car. ;)

Yeah, but I bet you WISH you did, and we'll fix that once I get it running again. Anyway the experimental nature of it was the main reason few people drove it and also why I didn't often offer. But as you'll recall I drove it pretty hard myself and I think it's safe to say that whatever damage it accumulated was at my hands. At this point the driveline is the remaining weak area and that is being resolved, but I'd also like to stiffen up the bracing on the wing, improve the front suspension, and add a removable rollbar. I feel very confident that I can eliminate the weaknesses of the engine this time around, as I'm no longer looking for as much power as I can squeeze out of it. I'll have to have good tires on it first of course. It can be a handful if you're not ready for it. At one time it developed a knack for dancing on the back tires if I put 'er down at freeway speeds and to say the least that was exciting. I'm not saying the front wheels were off the ground or anything like that, but it would alternate traction from one side to the other and "dance" back and forth very aggressively. A wrong reaction there could have been very very bad. Of course adding as much as 30% more power and 50% more torque could bring that back so I'll do some testing first.

I've not spent much money on the car at all. $100 transmissions, $1000 engines, discarded axles, heck I only paid $1100 for the car itself. It's been very rare that I've spent over a thousand on anything, and over the length of my ownership I'm quite confident my average cost has been well under a thousand a year. I don't think that's too bad for what I've accomplished with it. But then I've just never had a real big budget to work with. Even the paint was a carport home job costing about $700.

Dan calls it a "Monster Ego Trip" and he's right. People are constantly waving, pulling up at lights and yaking, making circles in the air, and stuff like that. Even pulling it creates excitement. But it's been that way for so long I've gotten used to it and it doesn't feel out of the ordinary at all unless it sits parked for awhile. Then I start to get withdrawal symptoms and work resumes a feverish pace to get it back on the road. Guess I'm hooked.

Jim



Edited 1 time(s). Last edit at 09/18/2008 09:02AM by BlownMGB-V8.

Carl, you missed it. Next time he offers, take it for a cruise! It really is a trip!

I only mentioned it cause I didn't want anyone to think I blew it up. :)

Now why would anyone think that? Been blowing up cars Carl? :-) Is there something you've not been telling us? :-) Actually I suspect Dan felt like the whole world was conspiring against him at that point. His car had been rejecting the transplant all weekend stretched out to 5 days and then this? At least it must be comforting to know that none of it was his fault.

The teardown continues and the engine may come out today. Down to the last 5 bolts. I made a pretty cool rig to hold the tranny in place, try to take a photo of it later. You can tap the top two holes of the bellhousing for 1/2"-13 and use a couple of short bolts, short length of chain, 2x4 and some all-thread and have an adjustable jig that will hold the tranny up while the engine is removed and reinstalled. This eliminates the hassle of dealing with the shifter and driveshaft.

I've also done some work on the IRS. Seems the angle wasn't quite right so I cut and re-welded the rear hanger arms to change the angle. It'll adjust the pinion from about -1* to 10* now and my driveline is at 3* so that's all good and there's room for mount compliance. I've also done some more layout on the forward brace. These changes will be incorporated into the Roadmaster also when it's IRS is transferred to the new body.

Jim



Edited 2 time(s). Last edit at 09/19/2008 08:41AM by BlownMGB-V8.

Been getting a little work done on the IRS, I'll try to get photos tomorrow. The cross brace is made (both of them) and I've rough turned the half-shafts. The hollowbar remnant from what we used for the Roadmaster is just a bit short so I'm going to get another piece, and I've ordered a length of 19mm drill rod to see if it's the right diameter for the bolts. 5/8" turned out to be .002" too big. I could polish it down but that's a lot of work and I'd rather just buy the right size. I've cut out blanks for the rear and center tie bars from 1/2" aluminum plate and the front one will be part of the isolator mount to the crossbar. I haven't quite figured out how I'm going to do that part yet but it'll come to me.

The setup in this car needs to be just as solid as the one in the Roadmaster. Odd as it might sound, I'll be seeing torque and horsepower figures in about the same range, possibly even higher. Consider for a moment that the stock numbers for the 340 were 260 hp (somewhat mundane) and 365 ft/lbs (exceptional). How they came up with those numbers I have no idea, considering that both tq and hp match at 5250 rpm or near thereabouts. The tq curve must be dropping like a rock at that point. But we've altered the system. The build will allow a higher redline and the blower will support it. Equal length headers will boost the max output. Even with a stock cam we're looking at an additional 1/2 atmosphere of pressure pushing past the valves.

Now there are a lot of variables to take into consideration but just allowing for one, the extra intake pressure, we could reasonably anticipate a roughly 50% increase in output. That alone puts the horsepower at 390, a mere 10 hp short of the mighty 455. Do the same with the torque and we're at 547.5 ft/lbs or almost 10% higher than the 455's 500. Considering that I've got bigger rear tires I think y'all can see the reasons why I think the IRS needs to be just as strong.

But on the other hand, the "Taxable horsepower" of the 340 was 45 hp. That plus 50% is 67.5 horsepower. THAT's the figure I think I'll use whenever anybody asks. ;-)

Jim

Back to the IRS. It turns out that the half shafts off this unit cleaned up at 1-1/4" diameter well enough to be able to use that size tubing, where the ones for the Roadmaster were at 1-3/16". I also have on hand a 19" piece of left over hollowbar stock with a 1.230 bore and 3/8" wall. That's heavier than I need but otherwise suitable, so I think I'll use that to weld up the half-shafts and then possibly turn 1/4" off the OD of the tube if I think it feels too heavy. Certainly that's quite a bit beefier than needed. It's a little more work but easier than going out and finding more tubing.

Dale has the 340 engine parts and I just ordered a set of main studs to be sent to him so he can get started with the machine work. He'll probably have to mill the bolt holes in the center cap slightly to allow proper alignment of the thrust surfaces, but the studs should give more strength in that area.

When ordering the studs I talked to Mike at TA and he said they are on track with the new Rover style heads so I'm guessing we'll be seeing something there next year. They've about finished up the aluminum block for the BBB and those heads are next in line after that. They have not yet fully machined any of the blocks but I know they have a batch that have been cast and cleaned so it won't be long. The drag guys are champing at the bit. I couldn't get a weight figure from him because the machine work wasn't done but as soon as I can find out I'll pass it on. I can't imagine it'll be any heavier than my 340 but a lot might depend on what crank is used. I also suggested that with manifold spacer plates these new heads could be used with the 340 and 350, but Mike feels he can get better flow from a dedicated head for the 350 so I don't know how closely he will look at applications for the larger SBB's. The 340 is something of a red-headed step child. Time will tell, but at least I've made the suggestion.

Jim

Progress continues on the 340 block. Dale found some inconsistencies with the mains, as I had as well. There was a sideways shift in the center mains of maybe a couple thou and the rear cap was a good .005" too big. It had to have come from a different block. But, to his credit, Dale was able to bring it in and get the mains to clean up with just a very narrow band on one of the mains by the parting line that didn't clean. I can live with that. The decks were off a bit and the bores weren't perpendicular to the crank but with .020" to cut he was just able to clean those up as well. That's the good news.

The cylinder walls are a little thin in a couple of spots. There was some core shift with the worst spot being about .130" thick on the thrust side of one cylinder. There's another place .110 thick but it isn't a thrust surface and shouldn't be a problem. I'd be a whole lot happier with a more or less uniform 3/16" wall but I don't have another 340 block to check. V8Buick guys suggested pouring in an inch of devcon but I'm concerned it may reduce cooling and may not stay put long term. So I think we're going to go without it. As Dale says, I'll be the first one to know if it isn't strong enough.

Anyway I should get the pistons ordered tomorrow, and maybe the head studs and MLS gaskets as well as some seals and other minor stuff. Then we wait.

In the meantime, today I cut and squared up the tubes for the axles. I need to finish turn the Jag half shafts to fit the ID and then I can cut and weld. Next step after that is to disassemble the jag hubs, turn the pilots to fit the holes in the vette wheels, put them back together and begin final assembly of the IRS. At that point I'll have to polish down the 5/8" drill rods to match the jag pivot shafts.

Those pivot rods have given me quite a ride. I began by ordering a length of 4140 heat treated, only to find the process had made the stock oval. It was not available in TGP (turned ground and polished). So I bought 2 lengths of 5/8" drill rod, which turned out to be .002" oversize and for 4 shafts (2 for this car and 2 for the MGB Roadmaster) that's quite a bit of polishing. So then in an apparent mental fog I somehow thought I was using 3/4" material and with 19mm being .002" smaller I ordered some of that. Special order of course and I couldn't send it back. Which left me ordering another 2 pieces of 5/8" drill rod. Some days...

So I have a fair amount of polishing to do, and then things will start to go together. One last piece of the puzzle is what sort of isolation pivot I will use for the forward end of the pivot rods. They have to allow the LCA's to rotate, be capable of vertical adjustment for the pinion angle changes, have room for a nut to go on the front of the rod, and have a cushion of some sort. I may just set the pinion angle at 3 degrees on this one (which is what both my engine and the MGB Roadmaster's engine set at) and forget the vertical adjustment. But I have a little time to think about it, I'm sure the answer will come to me.

Jim

Got the half shafts finished and a coat of paint on them today, I'll try to get some photos tomorrow. That was something of a job. I did end up turning 1/4" off the diameter of the tubes. It will make an interesting visual reference to see the completed pieces along with a chunk of the 2" hollowbar and some of the 1-1/2" that we used for the MGB Roadmaster. There is no doubt these axles will be stronger, but it's probably serious overkill. It will be interesting to see if we are able to twist one of the smaller ones used in the GT. I'll mark a straight line down each tube we can use for reference and then we can check it after some hard launches. If we do manage to twist one we can still probably turn it down to 1-1/4" on the ends and weld in some of the 2" hollowbar, if I can find enough tubing. Most of the scrap pieces I have have got holes and flats in inconvenient spots.

Anyway I also broke down the Jag uprights and degreased them. One bearing at least will need replaced and I haven't disassembled the LCA pivots yet. But at least I can go ahead and machine the hubs. Not bad progress, if I do say so myself.

Jim

The gears have been ordered, a set of good used 3.54's from ebay for $65 including shipping. So the next step is to finish the cleanup of the uprights by breaking down the pivot bearings and then tear down the differential. I've set up Dana diffs several times so this should be fairly easy, especially since the posi is already there. I found enough damage in the upright spindle bearings to require complete bearing replacement. Very likely the pivots will be similar. Apparently water got in on one side.

Also the piston order has been confirmed. By the time everything is added up we were at $1100 and change for pistons, rings, floating pins, pin oilers and double spiral locks. But that's still quite competitive with the import manufacturers and I'm happy to be supporting a domestic company with a rich racing history. They seem like good folks at Venolia, and treated me quite well.

Jim

Here is the photo I promised:



The long tube is 1-1/2" diameter, the short one is 2" and the half-shafts are 1-3/4".

Below are a couple of different front covers.

First, a 215 cover with a 300 water pump, as used on my 215 blower motor:


Then a bare 300 or 340 cover:


Not much difference there except for some of the accessory bosses, but notice that the timing pointers are located on opposite sides. The 215 cover will work just fine on the 340, and a one piece neoprene seal will fit both covers. A two piece neoprene seal is a drop in fit for the rear main seal as well.

The oil pump extension housing is a straight shot to the oil filter. We need another of these for the MGB Roadmaster project if anyone has a spare.

I have been working on the Jag differential setup. The standard generic Dana 44 ring and pinion looks like it will fit just fine. The ring used 3/8 bolts instead of the 7/16" bolts used by Jag so bushings are used to take up the difference, a standard proceedure. The Jag uses a larger inner pinion bearing than most D44 housings, the generic D44 pinion yoke is used which has a fine spline which also eliminates the troublesome 4 bolt flange, and the standard D44 pinion seal is used. I haven't installed the seal yet but it looks like it should fit.

The 2.88 pinion was marked +5 and the replacement 3.54 one +3. I had .030" in shims behind the large pinion race so replacing it with .028" in shims should put the pinion right where it needs to be. A contact pattern check later will verify that and any need to change it. Next step will be to select the right shims for pinion preload, and then the carrier can be installed and checked for backlash.

The thing about setting up a dana diff is that you have to assume it will be coming back apart a dozen times before it is set up right. It's a labor intensive job but there a few things that can be done to help. Use a non-locking nut on the pinion until final check. Use setup bearings for the carrier to set backlash and preload and only install the bearings that will be used on the final assembly. These setup bearings are good used bearings that have had the bores opened up with a flapper wheel so they are a slip fit. Then it's basically trial and error until the preloads, backlash and contact pattern are all correct. At that point the good bearings are installed as well as the pinion locknut and everything gets locktite. I hope to reach that point next week sometime, then I can begin assembling the suspension. The first decision there will be whether to use the stock timken bearings on the lower pivots of the uprights or to use the delrin bushings like we did in the GT. I'm leaning towards the timkens just so we can look for any differences in the way the suspensions react.

Jim

News from Venolia, the longest 3/4" piston pins available were a bit short to use spiral-locks so we're going with teflon buttons for pin retainers. The pistons should hopefully ship this week.

Work continues on the differential. Think I was kidding about a d44 having to come back apart a dozen times? I'm up to about 9 just setting up the pinion. The Jag large bearing is used but for the small bearing something a little more special is required, as the generic pinion shaft is 1/16" smaller and the generic d44 small bearing is too large at the outer race.

The correct bearing is Timken # 02474 (bearing) and 02420 (cup). You need these numbers if you want to put a u-bolt type yoke on a Jag diff with generic d44 gears.

There are a few tools that are just about indispensable for this job



First, a stationary pinion flange wrench (channel iron) is extremely helpful



Next a pulley puller to remove the flange



And finally, a dial indicator of some sort. It is possible to get the job done without one of these, but it does remove some of the uncertainty.



Next comes installation of the pinion seal and test fitting of the carrier, checking backlash, and if it is within limits, checking the contact pattern. It'd really be nice to get lucky on the backlash but it's unlikely, so removal of the side bearings is almost certain to follow.

Jim



Edited 1 time(s). Last edit at 10/22/2008 03:54PM by BlownMGB-V8.

There's been a bit of a setback. Turns out the vendor I bought my gears from sold me reverse cut gears without listing them as such. How that will be resolved is yet to be seen, but of course the worst of it is the time invested to get another set of gears and set them up. To say the least I'm a little unhappy about that. So that will slow progress a bit.

In the meantime I've ordered seals and bearings for the uprights. I am going to convert the spindles and cross shafts to a gear oil bath instead of grease pack. I think it will be more effective in keeping the bearings lubricated and easier to service. I've ordered nitrile seals to replace the felt and leather ones and will install flip caps for the filler holes assuming that I can find them, and then use synthetic gear grease. The needle bearings on the inside end of the LCA's will remain grease packed since there is no cavity to be used as an oil reservoir. An o-ring will be needed between the seal inner journal and the shaft but a thin one should nest in the corner radius of the journal and the bearing race. On the spindle I'll use an o-ring if I can, or a sealant on the spline if not.

I might get a chance to begin reassembling the half-shafts today as well.

Jim

Jim, for all types of oil cups and filler adaptors check McMaster Carr. Page 2138 in their catalog. [www.mcmaster.com]

Thanks Bill, I never even thought of that. I checked sizes, and they have a push-in style that will fit the hub fill opening so I ordered some. I just finished installing the new spindle bearing races and seals and everything looks good at this point but the new nitrile seals were a very tight fit. Jag sized the bore for a 3.00" seal but the available common sizes are for a 3" bore. Since normal seal fit is .004-.005" interference these had more like .008-.010". Fit tolerance is +.003 to -.002" so in the best case we were .002" beyond the tolerance, and that's about what it was like to fit them in too. You wouldn't get them in with a hammer and a drift punch.

I'll tell you what guys, we should be real grateful to Dan for buying all those IRS parts for the Roadmaster. I've spent upwards of $500 just on bearings and seals and that's with re-using the old differential bearings. By the time you figure in new brake rotors and pads and add it to whatever he had to pay for the IRS that was about a thousand bucks he donated to the cause, and it's money we didn't have to spend.

I got lucky on mine because the brakes are good. So anyway, the half-shafts are assembled and once I turn the hubs they can be joined to the uprights and I can concentrate on the LCA's. Maybe by then I'll have another set of gears.

Jim

Here's the modification to the uprights. The flip caps from McMaster-Carr were a perfect fit in the grease fill hole. I bought 1/8" NPT threaded flip caps for the pivot shaft and drilled and tapped fill and drain holes. First I enlarged the existing small vent hole to use for filling and put the same size plug for a drain where the grease fitting had been on the bottom. I also drilled and tapped a drain hole in the spindle housing.



This allows both cavities to be filled with gear oil or another lubricant, I plan to use Mobil 1, and allows for periodic oil changes without a teardown. I think this will do a much better job of keeping the bearings lubricated and free from moisture than the old system and if I can find the right material to glue into the caps will probably keep the area cleaner as well.

Jim

The second new gearset came in, this is a new set of OEM gears that was used by Richmond Gear to set up their production and inspection so I got them at a good discount. Hundred bucks for new gears, and the vendor who sold me the reverse cut ones refunded my payment and asked me to please not send the gears back. Can't ask for better than that. I got lucky in that the pinion was a +3 which was the same as the pinion in the last set (the reverse cut Ford gears). That meant installing the pinion was just a matter of getting the preload set and that was within .003". I removed one shim and was at 16 inch pounds of torque with the seal installed. Feels just a smidgen heavy to me when I turn it by hand but I think it'll be OK. The spec is 10-20 for new bearings IIRC and I have one new bearing.

The carrier went in and meshed OK but the backlash is excessive. At around .100 just eyeballing it this indicates that there is indeed a carrier break between 3.08 gears and 2.88 ones. This is apparently a 2 series carrier and I need to find a 3 series. New cases can be had for about $230 so that is my target to try to beat. Finding a used 3 series Powerlok case shouldn't be that hard you would think, but the only thing on ebay were complete assemblies selling for about as much as new. This might slow me down for awhile. Once I've gotten the bill from Dale for the engine work I doubt I'll be able to afford more parts until spring. That could slow down development of the forward pivot, which the MGB-Roadmaster also needs, so if anyone has one laying around that they want to get rid of... I can probably work out a trade of some sort. In the meantime there are hubs to turn down and pivot rods to polish.

Speaking of Dale, I told him to go ahead and O-ring the deck. I ran across my copper head gaskets for the 215 the other day which got me thinking about the roughly $300 the MLS head gaskets were going to cost me. Well at about a "C" note to o-ring that's $200 I don't have to spend. I just have to enlarge the bore holes from 3.570 to 3.9 or so. Looking around the shop I found some pieces to make a punch and die set out of so I can do that in the hydraulic press. Every dollar counts.

Jim

More good news. One of my old friends in the I-H community has a 3 series PowerLok posi sitting on the shelf and ready to go. He sort of owes me a favor since I gave him an intake modified for port injectors with a fuel rail, so in exchange for the posi I found him an open carrier and set of gears he was looking for. I don't know if that qualifies for collecting on the favor or not, but I don't guess it really matters since we're both getting something we want. Merry Xmas! The important thing for me is that I'll soon be able to resume work setting up the differential.

All the machine work on the engine has been finished with the exception of installing the cam bearings. For whatever reason the rear cam bearing bore is undersize. I don't know how that happens, but Dale has the tools to fix it and that's the important thing. Apparently there is some warpage through the cam bearing area that will have to be cleaned up. So, I'm crossing my fingers hoping that's the last item and nothing else happens to delay transportation. Otherwise I just might be picking up the engine at the summer V8 meet. We knew about the problem with the cam bearings but unintentionally put that off while doing other things. I guess there's a normal sequence that you generally follow when preparing a block, and I should have made a point of dealing with that issue first but I didn't, so now we're dealing with it last.

Anyway, I'm still in the process of getting used to the cold, figuring out how much propane it is going to take to use the new furnace in the shop and such, and hoping for another warm spell. I've been pretty surprised that so far as I can tell it hasn't dropped below 38* in the shop yet and I'm trying to calibrate the thermostat to keep it above 32. With those old style mechanical thermostats you can rotate the housing off level so that instead of 55 being the lowest setting it'll go on down. How much rotation it takes to hit 32 is the real question. It looks a little strange but it works. Maybe I should try to get one of the round ones if I get a chance.

There's a naturally occurring sequence for setting up this rear end too, and rather than carry the dial indicator back across the shop to dial in the hubs on the lathe I've done other tasks while waiting on a posi. That wait will soon be over and once the lathe is freed up I will move on to polishing the pivot rods. I don't know how much longer I can put that task off, undoubtedly once started it'll go fairly quick and be easier than the anticipation. But it's kinda like drywalling the basement. One of those tasks that has to be done but about which I cannot seem to find one solitary thing to like. Ah well that one I can put off awhile longer. The basement, that's another matter.

Jim

And now, we begin to see some of the things that tend to make a swap such as this one difficult. There was a breakdown in communication apparently between my buddy Scott and myself, and instead of there being a 3series Power-Lok diff in the box when it came, I found a Trac-Lok. While your initial reaction might be, "Hey that's good, it's a great posi." mine was a bit more subdued. Within a day or two I knew there was good reason for that too, but two positive things came of it, and I was able to confirm that, yes indeed, there is a split between a series 2 and a series 3 case, somewhere above a 2.88 Jag gearset. Incidentally, for those curious to know, the Jag diff is called a Salisbury, apparently for the area of England in which they are made, and they are manufactured by the Dana/Spicer corp, on the pattern of the Dana 44 but with the above noted variations. It appears that they do use the same side bearings.

The Trac-Loc would bolt right in and only has 6000 miles on it, but it has 30 or 31 spline side gears so it will not mate up to the Jag stub shafts. I could buy the correct side gears, but I could also sell both units I now have and buy what I want, and at this point that would be a True-trac. It looks like there may be another flurry of ebay activity coming up as I attempt to generate funds for the rest of this upgrade and tidy up the place at the same time. It looks like there will be Olds and Buick engine parts as well as other driveline pieces, and even a pair of T-50's and a bellhousing and flywheel. But right now I'm battling the winter doldrums so it may take me awhile.

The good news is that Steve will be here Thursday, bringing the 340 with him. I'll need to get the Olds off the engine stand to make room for that one, but on the plus side there will be a nice box to ship a short block in. (I think) Then that engine can go together slowly and with plenty of photos for this thread.

I expect Steve and I will be able to feed off each other's enthusiasm for the MGB Roadmaster project and move things along there as usual and since the two projects are entertwined to some degree it should help some here as well, at least concerning the IRS. Anything to get that moving again would be a benefit as this diff business has stalled it out pretty effectively. The other good thing is that there should be an invoice packed in with the parts so although I'll have a bill to pay at least I'll know how large it is, and whether or not my with-holdings in anticipation of it have been sufficient. It could go either way, so it'll be good to know, regardless.

One of the entertwinements is the IRS crossmember. I corrected the angle and trimmed the corners of the mount for the one to go in my roadster, but now in all likelihood we'll put that one in the Roadmaster and I'll modify the other one in the same manner. That will leave the attachment points for the coil-overs to sort out. I've run into an unexpected complication there in that if the pin for the upper mount is square with the crossmember beam, it will not be square with the body of the shock, and since the design of the crossmember allows 6* of angular movement that complicates the matter a little. It shouldn't be a problem with heim joints for the attachment points but may limit other choices. We'll get it all sorted out eventually, but it's not going to be today. Tomorrow isn't looking real great for that either. But the important thing is to keep on doing the small tasks so eventually it does get done. Hard as that may be some times, it's the surest way to the finished project.

Jim