SBC to BBC conversion.

[gunshotwoundshurt]

74 gmc with 350. How much of a pain is it for a swap to the big block? Any and all info and advice is greatly appreciated. Just score a newer 454 from a friend for free. He put in a new 572. Drove in the car with this motor many times. Only 5k on the motor. Help me out guys.

[Pyrotechnic]

Not too big of a deal. Biggest difference is the accessory brackets and of course you will probably have to rearrange your exhaust a little bit. If you don't have a 4 core big block radiator, it's a good idea to get one. If running a Turbo 350, make sure it is in good health and a shift kit is a good idea.

A new 454 for free ? You must have some really generous friends.

[d10s69c10]

not hard at all. really just a drop in.

its heavy so your front might sit about 2 inches lower.
if you dont have pullies/brackets could present more work.
Needs a bigger/aluminum radiator.
if your foot is heavy/ tranny will suffer.

[Albatrossian]

A 454 for free? Hey, I'll be your best friend! I wonder if theres alot of weight difference between the 396 and the 454..
Hmm..

[d10s69c10]

Originally Posted by Albatrossian

A 454 for free? Hey, I'll be your best friend! I wonder if theres alot of weight difference between the 396 and the 454..
Hmm..

kinda goes both ways. aluminum motors to steel ones. 2 bolt to 4 bolt all these things can be taken into consideration. 396-632 396 has the most metal in the cylinder walls and a 632 has alot less metal in the walls...

i think the 396 is one of the heaviest correct me if i am wrong.

[gunshotwoundshurt]

I have a new turbo 350. Its been built with a shift kit and all the goodies. This 454 is REALLY strong. Might have to adress the tranny and rear end.