chevy 302

[sleeper05]

i see that the chev 302s are rated at 290 hp, but i have heard rumors that they were actually around 375-400. Is any of this true??

[black84z28]

yes...very much true

[92rs25th]

But the 302 boss motor will kill it , so i've heard. Not actually bothered to verify it though. And the 351 cleveland kills the 350 4 bolt.

[black84z28]

Originally Posted by 92rs25th

But the 302 boss motor will kill it , so i've heard. Not actually bothered to verify it though. And the 351 cleveland kills the 350 4 bolt.

the z/28 trapped 14.3@101 compared to the 14.5@97 in the boss

[CORE402]

Man you people really need to know what you are talking about before you just start shooting things down or saying this will kill this no problem. The boss 302 was a baaaad little motor same with Chevy's 302. The 1970 LT1 was right there with the 351 cleveland. They are pretty much the same. They are the same displacement and very similar designs. Clevelands may have some advantage with their crazy heads.
Back to the original question. Yes, the old 302s from 67-69 were rated from the factory with "290" horsepower. However, it made more like 390hp and with simple mods it could reach 450hp.

[CORE402]

I really want to build myself a 302. Is there an aftermarket rotating assmebly to turn a 350 into a 302? That would be one hell of a fun car to drive!

[92rs25th]

You'd be better off geting a 400 sb.

[CORE402]

Well I would also be better off with a 472ci SBC Dart motor. Hell might as well get a 572 or a 632 BBC. It isn't always about displacement, sometimes it is about nostagia. Dont get me wrong I love displacement that is why I have a V8 and I do plan on building up a 400 SBC someday. But I would really like to build a 302 SBC too. A Camaro whose motor that revs to 7k would be pretty exciting to own.

[92rs25th]

Yes 7K out of a v-8 is nice.

[bigbadbowtie]

302 (chevy)cubic inches can be had from

283 small journal crank.
327 small journal block
5.7 rod
set of 302 pistons.


You will need a big gear,4 speed or BIG stall to get the power out of this engine. Not really a street engine.

PS 7k can be had out of any SBC.... I turn my 355.. 7200

[CORE402]

I know how they were made I was wondering if there were companies out there that would make me a crank to turn my medium journal 350 into a 302.

[89IROC&RS]

to answer the question, as i have done alot of research into this, (also search for my thread "new hope for my 302" in this forum) there are no current offerings to make a chevy 302.

the solution is this, get a post 87 350 block. one peice rear main seal, hydrolic roller camshaft equipped and all that. then hit up the junkyards and find a caprice wagon or coupe with the 4.3L LT1 based engine. and get the crank out of it. and also the connecting rods if you want. this crank is the same specs as the original 283/302 crank. 3in stroke, large rod journals, 350 main journals, and a once peice rear main seal. so it will create a modern 302. this is the method i am using for my 302 which i am building. a 99 tahoe 350 block with vortec heads, and the 4.3L LT1 crank.

but i will warn, that the 302 lacked a street following because it was a race motor. low end power was lacking drasticly but in high end rpms they were monsters. Im fully expecting this in my camaro, and wont be dissapointed by some loss of low end power. for others building street driven camaros, a 327, 350, or even 400cid sb would not be a bad idea.

[89IROC&RS]

oh and i forgot, the 4.3L crank is cast iron, so it will handle up to 400 safley, i plan on using an extreamly lightweight rotating assembly that will be painstakingly balanced and blueprinted, and ill be pushing it to 450-500hp. if anyone wants a 302, and wants to run say a twin turbo or nitrous injected setup i suggest getting in touch with scat for a custom made crankshaft. the downside, is that they only offer custom billet cranks, not forged, so they cost upwards of 2,000 dollars, the upside, youd have to be one helluva goober to break it.

[CORE402]

I am betting you have already thought of this but for my own knowledge, can you take a 283 crank and put it into a 350 with the use of some spacer bearings? Similar to the 377 idea, taking a 400 and putting in a 350 crank?

[CORE402]

Would a 307 crank work in a 350? Making a 327 seems to be a little more cost effective then a 302. Could one also put a 350 crank into a 307 block?