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MG MGB GT V8 Factory Originals Technical - All right, I'll do it!!

Hello,
I have been ready with much intrest about the gm 2.8 v6 conversion and I confess I have been afflicted and the only cure is the conversion. I just am having problems discerning what car to get the motor from. I wan't to use the carburated 2.8 and a 5 speed t-5 (or whatever version will work well with the 78 RB rear end. I will use Bill guzmans kit. I am trying to keep the cost down and will be doing most of the work I can do on my own. So please hit me with some of the particulars about the donor cars year, make and models.
also what kind of clutch setup and drive shaft.


thanks for your help,
Andy
andy heston

Andy:

I have researched this to death, So have others and lots in the archives. Buy a 1990 or later Camaro/Firebird drivetrain. You will need to retrofit the carb and distributor, but no big deal. Call one of the conversion suppliers and you will be there.

Pete
Pete

Pete,

Would a '90 or later also get you the "world class" T5? Or did that start later?

Michael
Michael Willis

Andy,

I tried you email address. But, received an undeliverable response. Where are you in Arizona? I also reside in Arizona, Peoria, and have a '78 that I will be converting.

Michael
Michael Willis

Michael,
I emailed you did you get it? I live out in the outback in yuma. drop me a line at hestonma@3mawyuma.usmc.mil


andy
andy heston

Michael:

Not sure about 90. Seems that was the changing point. What I recommend is a T5 fron a V8 car. It will have a .63 OD and will work with the 3.9 rear end. Not all V8 T5s have the tall overdrive. The problem with T5s is that if they are for sale used, they have probably been used-up by the previous owner. With the cost of a re-build, its best to buy a re-built unit or go new.

Pete
Pete

Wouldn't the bell housing have to be changed if you use the V8 transmission with the six-cylinder engine. The six is more narrow that the eight.

Considering do the six-cylinder conversion as well.

Zach
Zach Dorsch

Yes, You need a V6 bellhousing. It will fit the V8 trans. The bellhousing swap is a lot easier than the rear gear swap.

Another thing to consider is the clutch. I believe you will need a hybrid of V8 and V6 parts to fit the splines and flywheel. Do not forget that this swap will also require a hydraulic throw-out bearing.

Pete
Pete

what would be the problem with using the v6 s speed tranny? is the 5th gear a different ratio. would it work with the stock rearend.
andy heston

I have a 3.4-litre V6 and T-5 from a 95 Camaro/Firebird. I've measured the ratios so I'm not guessing or quoting from specs: first gear is 3.75 and fifth/OD is .73. My protractor is not 2 ft in diameter, so these may by off by a hundredth or two. First gear will be far too "low" with the std B axle of 3.91. You will end up using second gear for startoff and ignoring first: ie - you effectively have a four-speed. The fifth gear ratio of .73 is not bad, it would give about 2400RPM cruising at 60MPH. But you really want a 3.31 or 3.07 axle ratio.

As Pete says, the V8 box is better suited. First gear on the "world class" version is 2.95, and fifth/OD is .63 or .65 - something like that. Much more useful with the std axle. There are apparently some variations in ratios on T-5 boxes, esp. the V8's, so don't take all this as gospel...take a protractor, some glue, and wire pointers and prove it to yourself before you pay for any gearbox.
Bob Wilson

Andy, Your e-mail is disabled. If you want to do a proper 60 degree conversion, give me a call. I am not in the business, but there is a much better way than the rwd Camaro drivetrain route. The rwd conversion may seem better on the surface, but it 'aint the way the go regardless of what anyone may say.
David Gable

David,
thanks fro the reply I sent you an email. so fire away.

andy
andy heston

David,
I just recieved my email back that i sent you saying your address is not there. try me at hestonma@3mawyuma.usmc.mil this is my work email. i will look at my email to you closer and see if i screwed up something.

andy
andy heston

Hello David,

I was going to purchase a Camaro for my 1980 B conversion, but I am looking for something better. Please send me the info you sent Andy, Thanks a lot,

Angelo
Angelo

David,

I also tried to send you an email without success. Since many of us seem to be interested in your information. perhaps you could somehow post it?



Stan Arendts

Yes, please do post the information David, or, get back to us at our email adresses left here. Thanks in advance.

Michael
Michael Willis

I checked my T5 and since it has a bell housing which mates to the 3.4L and 1st checks at 3.75 ratio, 5th at .73 it has to be a V6 unit. Previous postings said a 26 tooth input spline and 27 output makes it a V8 tranny don't seem correct as my 94 camaro tranny has both??
Anyway, The motor was from an automatic and since I am going to stick I will need the input bushing in the end of the crank which supports the trans shaft. Anyone out there done this??Will a stock bushing do it?? Or is my machinist going to get richer??
Thomas Rynne

Your machinist will have a little more of your money, but probably not be too rich. He'll inlet the crank for the stock bushing, not a big deal. I've seen these bushings offered with roller bearings, but don't know if this gives much advantage.
As you probably know by now, T5s parts get mixed and matched quite a bit; the main thing is that you end up with a stout tranny. Also, parts are readily available for rebuild, and there are videos out to guide you thru it. Doesn't look too difficult, but you need access to a fairly big press at some points.
Joe
Joe Ullman

This thread was discussed between 13/09/2001 and 02/10/2001

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