So this is purely hypothetical as I am currently in the middle of another build.

What would be the pros/cons of building an SB2.2 headed 302?

Now obviously it would be expensive. But can you find a quality forged bottom end for the 302? I don't mind doing custom pistons.

My thought's are that a 302 is already inclined to run at 8000rpm so I might as well have heads that run that high as well.

Power goal is 2 per cube, if not a little more.

Thanks in advance for your input,

Jeremy

 

Jeremy, there is no point in building a 302 unless you have to per rules or are running a pounds per cubic inch class and that's what you needed to run for car weight.

It's true that a 3" stroke engine is happy in the upper rpm range, but it has to be. The lack of displacement means the engine is going to make less torque and that requires rpm to make horsepower.
I too wanted a 302 for my camaro and ignored the advice of my longtime engine builder friend and built one. What started out as a nostalgic tribute engine quickly changed to a large cc headed, large primary tube combination that I rotated 4 cams through and 2 sets of headers. My 11 to 1 302 would quickly rev to 7800-8000 rpm in the lower gears but just didn't have much smoke in high gear with the 4 speed.

I love the sound of a small block at high rpm and the 302 delivers in that area, but it isn't that legendary on the street when it counts.

Another consideration is that you will not get a synchronized transmission to shift consistently above 7500 and that's pushing it. The clutch disc has too much inertia and is difficult to slow down to make the shift. A pro-shifted transmission is necessary with its larger widow on the sliders and while it will shift any gear at any time they quickly wear out on the street and are clunky.

An SB2 headed 350-420 inch motor would rock the house and be large enough to use the heads potential. With a 7200 rpm upper shift point a manual transmission can get the job done and you could easily make your 600+hp with the proper parts.

This is my advice from the experience of having thrashed a 302 for the last 4 years or so.

Oh, and on the 302 shortblock, a DZ 302 crank can handle the power and rpm. If you get a set of 5.94" rods standard 350 pistons will work...there are a ton to choose from.

 

It really would be a novelty engine. I know, seems like a lot of money to spend on novelty.

I'm not so worried about the torque as I was planning on putting it in a car that weighs around 2200-2300lbs.

I know that there is no replacement for displacement. I'm glad to hear that the stock 69 crank can handle the power. But you are sure that it can handle 700hp and 8500rpm? And the pistons I thought I was going to have to get custom because of the heads.

If the bottom end prices out fairly cheap then I won't mind selling it later when I feel like building an SB2.2 434. Right now I'm just thinking about something small, that turns high and won't destroy a 2300lb car.

Good advice though, this is still a very tentative plan.

Jeremy

 

You don't have to go with the exotic heads to turn 8500 with the 302. You can use some 200cc-215cc intake runners on 23 degree (std) heads and the rpm will sing. For the 434 check out the Brodix 18X standard exhaust port heads. These heads use all regular valve train without the need for Jesel shafts, offset lifters or any of that stuff. They are fairly cheap also around 1500.00 a set. You will need the intake to match them and Ross makes some nice pistons for it.

 

The point is not entirely to turn the motor to 8500, though I may have made it sound like that. The point was 2hp per cubic inch of displacement, Naturally aspirated.

And for that matter I would try to turn the motor higher than that and also try to make more power, but I like to set lower goals and then "overachieve."

You're right though, you don't need to spend that kind of money to make rpm or hp. It's just cool to have an SB2 motor.

For the record the Brodix heads are something i've considered before and I probably will do something with them in the future.

Thanks,
Jeremy