What transmission do I need?

[mspear]

I want to install a 3.5L, twin turbo engine in a 79 911. Bought the car, as a roller, with Yellowbird bodywork. Seems like it would be fun, with an engine like this.

What are my options for a transmission? (I'm not overly wealthy)

The engine is currently mated with a G50 transmission. Does the 911 body need to be altered, for this drivetrain?

If I don't want to alter the car, am I needing a short bellhousing transmission?

I would appreciate any advice.

Mike

[Tippy]

G50 is fine. You can add a billet differential cover for added strength.

[RarlyL8]

The engine is currently mated with a G50 transmission

You answered your own question. There is no better tranny, and you already have it.
Now post pictures!

[Dr J]

The G50 will NOT fit an unmolested 79 body. Mucho bucks to make it fit.

[vintagecarlover]

Originally Posted by Dr J

The G50 will NOT fit an unmolested 79 body. Mucho bucks to make it fit.

Mucho bucks part may be strong. Go Coil overs for under 1200. And delete torsion tube center. Fab isn't a lot even if farmed out. G50 pedal assly and brake booster.

[Dr J]

Vintagecarlover, good answer, as I only considered the shortened bellhousing option where you do not modify the body.

[Matt Monson]

Fun project. You've got all the parts and pieces to make a monster.

[930cabman]

+1 with the G50

[SexOnTheBeach]

You can also use Californnia Motorsports rear flat end cover, if you need extra clearance.,

Originally Posted by Dr J

Vintagecarlover, good answer, as I only considered the shortened bellhousing option where you do not modify the body.

[vintagecarlover]

Gearbox still needs to be shortened according to Rodger at cal Motorsports. Billet flat end cap doesn't change that.

[YermanCars]

You can also shorten the G50.....

[Kraftday]

The 915, 225mm or the 930, 240mm 4Spd would fit easier. The G50/01 is the ultimate choice for a 3.5L but will require the bell housing and mainshaft to be machined shorter to fit the shorter chassis without removing the 911s torsion tube. Because the 911 chassis is shorter than the 930 some additional clearance to the torsion tube will be necessary. The support carrier mount would also need fabrication. The 87-89 911 pedal, hydraulic assembly and shifter will also be needed. Clutch to use is an early 76 Turbo, low profile clutch cover, ring gear and low profile bolt with G50 release bearing. Also engine block needs shorter studs. That is most of it. I can help you with the machine work, transaxle build and parts of you want to go this direction! It wold be worth it!

[Dr J]

... and we have come full circle to my original post.

[TurboKraft]

Mike -- the G50 conversion is worth the effort. IMO the ideal transmission for a street-driven 930, the close ratio gears of 2nd/3rd are just a blast. They're really durable as well, and the hydraulic clutch actuation makes it all the sweeter. Yes, the ideal is to disassemble it and have CA M'Sp shorten the mainshaft and bell housing. Really not that expensive. Gearbox disassembly & reassembly isn't that challenging on these cars, and it is good to know it's all healthy inside before putting 3.5L Twin Turbo power through it. Don't want to do the labor? Ship it to them, Bobby and Shawn with do the whole job and it'll look like new when you get it back.

[mspear]

Sorry, I've been away for awhile. Thanks to everyone for the options.

So, I need more advice. I'm committed to using the G50 transmission, since we bought an 86 cab that has this 3.5l tt engine and G50 transmission in it.

From what we can see, they cut the torsion tube and welded in gussets on the 86 cab body. Is the 79 coupe body different than the 86 cab body?

and if not, does that tell me that the G50 transmission has already been shortened?

Thanks again, this is an exciting project. We have a 3.2l engine and 915 transmission, to install in the 86 cab.

I'll have to learn how to add pictures.

Mike

[vintagecarlover]

U need to duplicate the torsion tub cut and swap it over. Will need Coil overs too. Trans doesn't matter then if shortened.
I used a different browser to load pics.

[Kraftday]

~$6K+ now to buy a 930, 4spd and fit fly/clutch. How fresh is the G50? If it has to be gone through, may as well convert it to G50 SBH. Some overlapping costs involved. For sure no regrets shifting through the best matched gearbox. Future value would also be there with that investment especially considering the bastard nature of your car (no snootiness intended!)

SBH machine with common rebuild with parts ~$3K range.

A proper rear coil over package is ~$1300+ now to do 935 style either way you go.

[mspear]

Kraftday,

No offense taken. This car came to us, as a Yellowbird CTR 001 tribute roller, with extremely high quality body work finished (but no paint, seats or drivetrain).

So, the project was already a bastard and my son and I are just building a hot rod.

That being said, if you're building a car that looks like Yellowbird, it best have pretty good performance to back it up.

Our decisions have been made.

We are installing the 3.5L TT engine, G50 transmission, front and rear coil overs and 993 Big Black brakes on the Yellowbird tribute car.

The body has been COMPLETELY disassembled and repainted this summer.

We're almost into snow season, so the plan is to have it roadworthy by next Spring.

I'm not very good on the website. Could someone send me detailed instructions on loading pictures? This is a fun project for us (I keep saying it's my last).

mspear13@aol.com

Mike

[Dr J]

Mike, now that the decision has been made, that will be an amazing car when you are done with it. Congratulations and looking forward to those pics.