Hey fellas - lemme know what you think about this one, its the result of my most recent brainstorming: I was thinking of building an honest 302 Chevy with the following parts and using it with say, a 5-speed TBI car. There'd be a LOT less computer modifications to go through, and the stock TBI would work at least initially without much changes. The only real limitations would be how high of an RPM the TBI and Distributor system could take. Gimme some feed back - I'm thinking now...lol

Small journal 283 crank (from 50's, early 60's 283)
Small journal 327 block
461 2.02/1.60 Heads - ported/polished/studs/plates
1.6 Roller Rockers (Increases lift w/o greatly affecting duration
and vacuum)
Roller Cam of some sort. lol. Wide lobe-sep, ~.450lift per side (LT4????)
9.5:1 compression w/flat top pistons
Reconditioned stock 283 rods (fairly reliable - then add ARP hardware)
ARP Studs in the mains/head bolts, ect to assure reliability
Edlebrock Air-Gap Intake w/TBI plate

This would yield a TRUE 5.0 (so you could tell 'stang owners they got beat by a 5.0 chevy and they'll think they got whupped by a 305, hahahahaha) that would turn 6,000 SAFELY and would probably have great throttle response and economy with the EFI.


Ty

 

Well, it definetely sounds like it would be a sweet engine. You might even be able to shoot for a little higher compression for a few more ponies. The only thing I see being troublesome is using an LT4 cam, as that is a hydraulic roller cam, while the block is not going to be set up for a hydraulic roller cam. To use that cam, you would have to use a retro fit kit i believe.
I believe the most a tbi can pull is 6,325rpm because of computer limitations. I believe the two ways around this are: 1) use a Commander 950 ECM(Holley), or 2) find someone who is good with computers and chip tuning and maybe they can hack(?) into the ecm via chip and get it to pull more rpms.
As far as ignition, you will definetely need a coil. I think Hypertech's is the most powerful, I use the MSD duel connector coil and it works great with my set up and doesn't fall flat on it's face like the stock one did at 4,500rpm. A box and ignition module would probably be a good idea too.
I think some long tube headers w/ exhaust cutout would be the perfect way to top it off.

 

right - good thinking. naturally, if i EVER did this swap it'd be a complete deal. Although, I was thinking that it would be really fun with a tune-port motor b/c then the computer would be smart enough to 'learn' the new motor's characteristics. and plus, it'd be neat to have a new-style 302 z-28. haha

ty

 

DO IT,
REALLY, that would be the sweetest thing EVER...
I understand about the MUSTANG thing... I love telling mustang drivers that they got WHOOPED BY A TRUE 305 ... "no way man, that's gotta be a stroker or a 350 or something" ... NO IT'S NOT... look under the hood and the print on the back of the engine...
MAN, chevy rules

 

i'm working on it. today i'mna make some phone calls about a 1955 283 and a small journal 302 crank and see what i turn out. whichever is in better condition (and cheaper) i'll go after. I'll keep u guys updated as i plug along.

ty

 

Though it sounds appealing to you now, I can almost guarantee that you will less than impressed since you will actually give up a ton of low end torque which will really hurt if you drive on the street. You would even give it up to a 305 believe it or not.
Even back in 67-69 when Chevy was making a 302 for the Z28 models, it was quite common for a 302 to get spanked by even the standard 4 barrel 327 V8 just for the shear fact that they had no ballz under 4,000 rpms.
A lot of Chevy guys think that since there are so many guys going fast with 302 Fords, that a 302 Chevy would be better. That simply isnt the case for the fact that the Ford has a much lower deck height at 8.2" vs the Chevrolet at approx 9.1"
The Ford also has 5.0" connecting rods and the Chevrolet 5.7"
The Ford cranks are also approx 10-15lbs lighter. As such, the Ford has a very light reciprocating assembly. The Chevrolet stuff was just too darn heavy. Yes, you hear stories of guys with 7,8,9 or 10 thousand rpm small blocks, but you will find none will stock rods or cranks. Plus they also dont tell you how often they have to tear them down to freshen them.
With TBI you will not be able to use a 302 Chevrolet to its full potential. Even the production TPI intakes wouldnt be enough as the runners are too long.
Now, the real reason why the 305 would make more torque is because of the same 3.48" stroke that the 350 uses.
If it was me, I would pick a proven combo such as a swap to a 350.
Btw, Chevy didnt make a 283 until 1957 and you wouldnt want to use and 55-58 small block as they did not have provisions for motor mounts (55-58 used front mounts) or for a block mounted starter.

 

interesting - although, for the time being i'm still trouble shooting my TBI 350 motor. lol

 

If you were He$lbent on building a 302 it would probably be easier finding a large journal 327 and just using a 307 crank. I would think these would be easier to find than the old stuff.

 

You could build a 302 with a late model block and crankshaft. Check this out. 1997 302/Z28

 

I've heard about teh baby-LT1 302 buildup, but it wouldn't work really without a forged crank. And for the 307 idea - a 307 uses a 327 crank, not a 302 crank *I think*.

Ty

 

I don't think you would have a problem with the cast crank in a tbi feed engine due to the limitations mentioned above of an rpm limit. A good balance job would handle the rpm and horsepower the 302 would make. Now if you have mpfi or a carb, things can (get) harry real quick, forged would be the only way to go.

Steve

 

oh yea you're right about the 307 crank. Well I've got an old 283 crank but I'm pretty sure it needs repair. It badly spun a couple of bearings. Ive heard of people that have welded onto crank journals and then cut them back down to spec. I'm pretty sure its forged and anyone is welome to it for the price of shipping.