I have a 91 camaro rs and im lookin at pullin out the 3.1 and replaceing it with some kind of v-8. What am i getting into? I'v been a mechanic for about 6 years so i can handle my own but just curious if anyone has tried this befor? If so what all is involved? or even just a a 350 or 383
thanks for your time
J

 

Read the sticky about a BBC swap at the top of this forum

 

To sum it up VERY loosely, its basically the same as the V6-350 swap, only space it at much more of a premium, the parts are more expensive (ex. headers), and the cooling system MUST be upgraded.

 

Blip the throttle on that 454 and you'll probably pop out the windshield.

 

It's just like Adam said, it's a tight fit and will be more expensive in general to do. You'll want a new rear end and definitely a new tranny the 454 is gonna fit just as well as a 396, 427, 502 etc. BBC's are the heaviest big blocks GM made IIRC, somewhere around 720 lbs stock, but the added cubes make up for the weight without breaking a sweat.

 

I know its gonna be a complete driveline replacement, what kinda tranny bolts up to the a bbc? The reason im lookin at a 454 is bc there so easy to come by back home. How difficult do ya think it would be to just get the motor and driveline put in the car just to drive it? Gonna be more of a track car so not too concerned with wiring and all that good stuff. should i go carb?
thanks
J

 

Most any tranny can bolt up with the right bell housing, I'd look at a TH400 or 200R4 for auto, M22 or T56 for manual. My car came stock with the TH350 and 8.5" 10 bolt which are still in there and they seem to be holding up just fine on the street. If I turned it into a track car I think I'd feel more comfortable going with a 12 Bolt or better. I would expect to tow a thirdgen home if you leave the stock rear end in there (7.625"?)... probably get you a few passes before shattering.

 

Lol dont wanna do that again, i have a 01 ss after a tune and cam with bolt ons the rear end went out.
What kinda tranny came stock with the 3.1?
I'v heard the 700r4 are pretty much universal also

 

SBC and BBC use the same bellhousing bolt pattern but as mentioned above, you'll probably want a TH400 or at least a TH350 tranny. Because of the wider bore spacing, a BBC has a longer block. The tranny location doesn't change and the engine mounts are in the same locating on a BBC and SBC so physically bolting it in isn't a problem.

A bone stock BBC is heavy but just about everyone uses an aluminum intake which drops a lot of weight. Headers, although expensive, also save a lot of weight compared to iron manifolds. My BBC with aluminum heads is about the same weight as an iron head SBC.

 

I'm assuming you have an auto already? The 700R4 was stock on thirdgens for most years, from what I've heard the 700R4 is pretty beefy, but it's near the edge of it's limits for a mild Big block 400-500 Hp is what I've heard they can take, my TH350 is similarly rated, the 200R4 and TH400 tend to be beefier trannies... I can't speak much from experience though, just what I've heard from other people... my '74 is the only Auto I've ever owned.
----------



Yeah if you spring for alum. heads and intake you'll probably shead 100-150 lbs.

 

BBC does NOT weigh 720lbs... not even with iron heads. Its closer to about 620lbs, and a small block is around 500lbs.

 

According to this site Chevrolet Big-Block engine: Information From Answers.com You can find a BBC stock at 685 lbs starting with the Mark IV's

I could have sworn I saw 720 somewhere... The rest of the GM "Big Block" lineup is significantly lighter (Pontiac, Buick/Olds).