hey guys, ole Roost just joined, nice site. I had a couple C3's back in the day, then a 4 and later a 5, i go to Mecum in Houston every year and couldnt help but notice how cheap the 3's are going for now. Which brings me to my question, it looks like you can pick up a perfect car for less than 15k with very low miles, now days 15k wont buy anything hardly. I'm thinking about finding a late car, 80, 81, 82, and put a motor in it, and i was on GMperformance the other day looking at motors, complete motors. I saw the LSX454 and thought my god what a car that would be, a 81 vette, mint, 15k miles, with that motor, I have a TH400 tranny to go behind it already. I just wonder what all problems i would have as far as hooking everything up, PS PB AC all that stuff, serpintine belt. I figured some of you guys have done it, maybe not the LSX but one of the other high HP motors they have, i first thought i would go BB till i saw the LSX, but it looks like it would not be to terribly hard to do. I think it would be so cool to have a nearly new C3 with that motor and come out with around 30k in the whole deal, and having 650 instead of 190 that everyone assumes you have. Where am i going wrong here....Roost

 

Well I don't doubt that you can put that big engine in a late C3, it will be a very expensive project. Just a set of exhaust manifolds is very expensive. Of course if you go with headers, you wouldn't need those. The next problem is going to be longevity of the drivetrain with that much horsepower and torque put on it. You'll definitely need to beef up that end of the project.

 

Shark, thanks for reply. The LSX454 is the same physical size as the motor that is in the car now. How GM did that I don't know, don't seem possible does it. I have a beefed up TH400 I had built for a BB that I never used, I am not sure how much the rear end can stand but the early c3's had some serious up. I'm thinking it wouldn't be too much money to get the rear end built up though there's not a whole lot to it and it has to be close to an early c3 which some of those had ****loads of torgue

 

I don't know how much the differential can stand or whether it was different for BBC early on but I do know that the half shafts and U joints were different for the BBC. Another consideration is finding all the accessory brackets that mount on the engine. I know the BBC will fit but not sure if the motor mounts are in the same place. They probably are though. Another consideration is the fact that an automatic transmission also multiplies the torque.

 

Exactly, that's the main reason I came here, figured somebody had at least done it w just a new LS motor, 6.2 maybe. That would be the same mount wise as the lax I think. Did you eyeball that motor on GM's website ? how do they get 454ci out of a sb, one helluva feat for sure. Now picture that motor in an 81 mint car w 20k original miles, OMG that would be a cool car, and rare, and run w anything. I'm thinking 25k turnkey, 30 at the most. Be a fun car, and I could care less about originality, Damm car only comes w 190hp that's sad, a new Chevy truck will smoke your azz, cant have that

 

Didn't realize that it was a SBC. Can imagine if the bore centers are the same as a regular small block how thin the cylinder walls will be. Good luck with your project.