This is just hypothetical and not something I'd do, but would it be worthwhile from a power standpoint? Say if you were a 305 owner and all over your car it says "5.0", if you dropped in a chevy 302 it would be mostly true still... might have a show car appeal even though a 302 comes out closer to 4.9 Liters.

Am I ?

Probably only worth it if the 302 was dropped in your lap for free eh?

 

Not worth it. 302 isn't much better than a 305, if at all.

 

I have to disagree; A 302 is similar to a 350 with a 283 crankshaft. With big bores and short stroke it is well suited to high rpms and really rev's up fast. 305's just don't even compare because you can't run as much cylinder head and cam as you can with a 302...

 

The 302 is a better engine than the 305. But if you build a 302, you'll have to build it to spin high to make enough power to keep up with the bigger engines like the 350. A good example was the old DZ 302... it was really fast in the '69 Z/28, but you had to spin it up like crazy to get going fast. They were pretty gutless below 3500 rpm the way they were setup, but once you hit 4000 or so, HOLD ON! Of course, those 302s were pretty radical engines... 11:1 compression, a mechanical cam with around 255*/260* @ .050, and a big (for a 302) 780cfm Holley. These cars usually had 3.73 gears stock, but really needed a 4.56 or 4.88 set to keep up with the big boys. Auto trans was not even an option because the low end power of the motor was so poor - 4 speed only.

That said, build a 302 with a modern cam grind and modern heads, get the compression around 10.5:1, put a good exhaust on it and a 650 double pumper, and you could have a really nice high RPM monster thats still driveable at normal speeds. You'll probably still need a 3.73 or 4.10 gearset though.

I know of a few 4thgen guys who have turned their LT1s into 302s with the short stroke L99 crank and LT1 block, and they like it. Not as torquey as it was in 350ci form, but has alot more "oomph" above 6000 rpm.

 

The problem with the 305 is the smaller bore size (3.73") limits the heads and valve sizes you can use, which limits the amount of airflow into the engine. Less airflow equals less horsepower. A 302 has the same 4" bore as a 350, but with a smaller stroke. Therefore you can use the same heads and valves on a 302 as you can on a 350. I would definitely bet you can make more power with a TPI 302 than you can with a TPI 305. However, I dont know of anyone who tried it, because a 350 is the most common chevy engine now, and everyone likes more cubic inches.

 

Unless you special order it, you'll have a hard time finding a crank to make a 302. Most 302's used the 010 4" bore block so finding the block is still easy. The small rod journal cranks to make the 302 are long gone and any you do find one it will be an old cast crank from a 283 not a forged crank to make a real 302.

For nostalgia purposes, put into a first gen Camaro or Nova would be worth while. The 302's were short lived and phased out when 327's became popular then even they disappeared when the 350's dominated. Any of these 3 will be better than the 305.

Back when the 302's were popular in road course racing, the engines usually screamed around the tracks at 8000 rpm where they could make the most power.

 

That's about what I was expecting... so you'd have to dish out some coin to get a crank that will tollerate the RPM to make respectable power up top.

 

Let's not forget that the Ford 302 is the same bore and stroke as the Chevy 302. They seem to move Mustangs pretty well without tons of mods or 4000 rpm power band beginnings...

Also, you can use old 307 crankshafts to have 327 cubic inches from a 350 block. I would only suggest this if you are on a budget and you have the stuff lying around but it's still better than starting with a 305. I like displacement and I think that going with the 400 for sale on this forum for 500 bucks is by far the best way to go!!!!!

 

If you have a 1 piece rear seal 350 block, it is easy to build a 302. Just need a 1994-1996 B-car 4.3 V8 crankshaft and connecting rods. The crank is a one piece rear seal unit with a 3.00" stroke and production 350 size rod and main journals. The connecting rods are 5.94" long, which make them exactly .24" longer than a regular SBC rod. The .24" is signifigant because it is exactly 1/2 the difference in the 3.48 vs. 3.00" stroke. That means you can use cheap flattop or domed pistons for a 350.

 

That is a great junkyard tip!! I knew I was reading this stuff for a reason!!

 

A 302 TPI car is a tough argument. Here's something to think about...

1. A small journal 283 crank can be used in a late model large journal block - you just need bearing inserts that are readily available.

2. The TPI system has a hard time making power past 5000 RPM...which is the floor that the 302 operates above and beyond.

In the near future I'm going to be building a nasty 302 Chevy to wind up high and prove the pundits wrong. They're a very capable motor and with modern technology (not some crap 461 heads...) I'm sure it'll make awesome power. I've spoken with some 'old school' circle track guys and they claim (claim) that the 302 is more efficient / advantageous if you're trying to reach the 2hp/c.i. mark.

Tyler