I just recently brought a 1972 Chevy Caprice. Factory was a 402BBC, so I am thinking about buying another one to keep it original. I really want to go with a 454 but wondering if I can get good horsepower out of the 402, any suggestions.. I want to be between 400-500hp.
to me unless the car is in perfect conduction there is know reason to go back with the 402. All big block cost alot to rebuild so you might as well get the biggest one you can
but to answer your question can you build power out of a 402 of course you can but its going to cost you either way and you'll get a lot more out of a 454
Okay thank you thats what I was thinking. Now I just need to figure out if I want to get a core motor and just have it rebuilt or just buy a brand new one.
Think of 402 as a "30-over 396 with a weak crankshaft". The main difference between 396 and 402 is the "cast" crankshaft in the 402. 396 had a nice forging, the same as 366 and 427. If keeping the revs under 6,000, the 402 crank is okay. A forging "drops in", as all the journals and spacing are the same.
454 makes a lot more low-end power. This is "better" for the heavy car. The 454 block is different, though, with a 1/8" larger bore size. It also has te 4" stroke to increase the displacement from 427. Non-performance 454s also have cast crankshafts. Forgings are desired for any "real" performance applications.
402 uses basically the same cylinder head as 454 of the same years. 100% interchangeable.
For a nice "cruiser", 402 is fine. It can be cammed and "tuned" to get good low-end and decent fuel economy. 454 will make more low-end power, as previously said. If response and performance are more important to you, 454 is probably the best choice.
Yes thanks, that helps alot. Im going to with the 454, but now I need to pick the correct one. What is the difference between 2 bolt and 4 bolt main and which should I go with??
I have a 70 chevy c10 truck with a 3.08 gear, th400 trans, and a 4300 lb curb weight. I have 2 big blocks that I use. one is a 413 (bored 396) and a 468 (60 over 454).
I use the same cam and compression and exhaust system with both engines.
To me the 454 makes much better power under 3000 rpms and then they seem to make about the same after that. maybe the 454 makes a little more upper rpm power but not much more.
I think I would build a 496 for a car that big or add a turbo and efi to your current engine.
2 bolt or 4 bolt doesn't make a difference under 600 hp in a bbc.
they both use 6.135" rods so there is no price difference there, and you will have to buy a set of pistons that have a shorter compression height, but like when buying 383 pistons over 350 pistons there is normally next to no cost difference between the two.
if you are going to have this built then i guess you could go with the 496/489, it is a little overkill as the 454 can make gobs of tq but just like people like to build 383's instead of 350's, i can understand it cause there is a minimal cost differecne between building the two.
I say cubic inches rule. If some more is good a lot more is great. No replacement for displacement, except turbo's, superchargers and nitrous.
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