MG MGB and MGB GT Tech Talk
June 8, 2007
Hi,
This is a really great website and thought it would be the best place to make my mgb engine rebuild a reality.
I am looking for an early 64 thru 67 mgb flywheel to bolt on to my 68 mgb 5 main bearing engine so it fits my mga transmission. If anyone can help me find one it would be much appreciated.
Thanks,
Liam O'Flaherty
Novato, California
Liam, you're sure you want a early 5 main instead of the 3-main? E-mail me and I'll check the stack. I think there is one left.
I had to go thru all this kinda stuff before and am dealing with something close to this right now, all this can get quite confusing. Here's the issues you have to deal with, MGA and maybe even 3 main MGB flywheel register differently on the crankshaft than 5 main flywheel. The the next issue you need to deal with is which clutch you are using if you are using the MGA clutch which has the same bolt pattern on the flywheel as a MGB clutch then the throw out arm on the MGA tranny will work, but if you're using a MGB clutch, then you need the throw out arm off a 3 syncro MGB tranny.
The MGB engine I just finished for a shop in Miami has a MGA that has my MGB engine going in it, and they want to use the Moss 5 speed, so the shop owner, myself and Kelvin Dodds have all been taking this week about everything needed to make this conversion, while this is a little different than your project, all the differences of these cars, their engine back plate, clutches and throw out arms has been part of our discussions, so this applies to you your deal as well. The throw out arm I'm sure of, the flywheel on the three main engine I'm not, on 5 main MGB engine, any of them, they all are flat on the crankshaft mounting side of the the flywheel, on the MGA, the crankshaft mounting side of the flywheel is countersunk and registers by fitting over the edge of the flywheel, The 3 main MGB flywheel is one I'm not sure of, but it it is countersunk like the MGA flywheel, it won't work with the 5 main crankshaft. Of course the difference between a 5 main 3 syncro tranny MGB flywheel and the later 4 syncro tranny flywheel is diameter, the the 4 snycro flywheel being a larger diameter.
Ain't swapping parts from different cars around fun? :)
Rereading this, you are right. It has been at least 5 years since the last swap to an MGA and those were to drop 18v engines in. It required changing the back plate and flywheel and getting the special conversion spigot bushing. It may also have required changing the front plate.
Bob Munch would know definitively, and his memory is pretty good.
Anyway, I'll check and get back to you.
Thanks for all your help you guys. Especially Hap's input since he just went through this one.
Thanks for all the emails regarding available flywheels from the 64 through 67 engines. I went with the one who had the complete package.
The resurfaced flywheel, new clutch, new throw out bearing and the mgb early throw out arm. I am using Doug Jackson's web site (mgbmga.com) and the mgaguru site and the MGA Tech articles for info on the conversion. None of them mention any flywheel counter sunk bolting alignment issues so I am just keeping my fingers crossed. I will soon know if there is any issues and I will report back.
You guys are the best.
Thanks again,
Liam O'Flaherty
marin mg