I'm currently in the process of getting an RX7 project started.. bought the body, the motor.. looking for a 6 speed, then its off to hinson.. I'm sorta curious though, after this car whats next? I just wanted to see what you guys thought about this its been in my head all day. I'm pretty sure I've seen some info on here, but a search only 1 or 2 threads with not much info.

Cammed Ls1/6-speed in an early 70's Opel GT.. I like how the car looks when they are done just right and flawless. Black interior, Red car.. Some nice wheels..

Now for a few questions:

I'm pretty sure these things are less than 2500lbs, any guesses as to what an ls1 swap would weigh? Are these car 50/50? How strong is the rear? I imagine not that strong because of the low horsepower rating.. How does the car handle? Is there any comparison to cars of today at all, or is it just terribly outdated?

How hard would it be to do this swap? Is it even possible?

Thanks,
Josh

 

The main differences in weight between stock and LS1/T56 Opel GT would be in engine and tranny. They originally came with n/a Buick 3.8s and I'm not sure what tranny. The main difficulty with the swap would probably be the increased engine dimensions. From what I understand, the rearend is pretty weak but I have seen some stockers with 3.8 Turbo conversions so I don't know, a better bet would be a more custom rearend to let yo get some rubber under the tiny fenders because I'm sure you will be having problems with the same thing as me in such a light car...traction. Good luck. P.S. It will probably be easier than the mid-engine Opel GT with the Allison 1710ci V12 .

 

Might want to learn something about what you're talking about before you call it fact...no Opel GT ever shipped with a Buick engine, or a six! They all had Opel CIH (cam-in-head...not really OHC but not really a pushrod setup either) inline fours. The vast majority were 1.9L's, but some 1.1L's made it out too. The only thing Buick about them was the dealers that sold them.

I (well, my fiance) had a '73 GT for some time. Great little car, we just didn't have the time and space for another project...it was just a lot easier to deal with paying for a Miata than it was to keep the GT running. I never had the engine out to measure, but from what I remember, you're going to be doing some decent mods under the hood to clear everything. That, and the GT's unibody isn't exactly what I would call stiff (all of these cheaply done convertible conversions make me wonder how they can still open the doors!) so, honestly, you might want to consider at least installing a rollcage, if not tube-framing the car altogether. An LS1 would seriously twist a stock-body GT.

The rear is nowhere near what you'd need to live behind an LS1, and it's set up for a torque tube anyway. On the plus side, since it's a live axle (just a simple trailing-arm setup) it really shouldn't be difficult to mount up a narrowed axle that can take the heat, and get rear discs while you're at it.

The handling isn't bad at all, stock. I'm also 99% certain they're below 2000lb. They do have an odd transverse-leaf front suspension (like the back end of a 'Vette) which I'm guessing you'd probably have to abandon to clear the LS1...but that's purely academic if you do tube-frame the car. Even with the added weight of an LS1 / T-56 (that T-56 is at least 100lb heavier than the Opel 4-speed box!) you should still be under 2500lb, which basically puts you dead even with an LS1 Miata.

 

You know, as soon as I started reading your response I got to thinking, I guess I was thinking of the Sunbird (?) and the other cars on that GM platform. And doing some reaearch on the internet, I have found hat 60° V6 swaps are popular, but there's a big difference between the 2.8s, 3.1s and 3.4s and the 3.8s. Sorry for my confusion.

 

I'll let you know when I get mine done. Mild CHI 4L with 8.8 narrowed rear. Going for fun street car. -Brett

Compperformance@hotmail.com

 

Love this conversion idea!