I have a 302 with numbers that match a cobra block. It also has cobra rods with .20 forged pistons. DSS push rods. 200cc aluminum heads. A mild cam, gt40 upper and lower intake. High volume oil pump. ARP head studs. A 70mm TB. Here comes the support, 450lph fuel pump(e85 compatible) 8an ptfe feed, 6an ptfe return, 1000cc injectors, with a 70mm on3 turbo.
Questions….
How much boost is this setup capable of??
How much boost/hp will this block handle(not a big concern)????
What would anyone change if any???

 

the block is what would be of concern depending on how much hp your looking to make . The factory 302 block tend to fail around 500hp. Some below that number some higher. A good tune may help manage cylinder pressure and live longer.Lifting head gaskets is another issue but the aluminum heads with studs help in that department. A 351 is a better choice for strength if your shooting for a higher hp. Most of your parts will swap over too.

 

After I smoke this block that will be the next route. And upgrade turbo.

 

12 an for drain minimum and if those Chinese 200 cc heads don’t give you a problem I would be surprised.

 

the other thing that tears up 302 blocks is high rpms. You might not want to blow it up since it could take out some of the parts you’d wanna carry over to the 351

 

the turbo is the only thing I would carry over. But that will get upgraded too.

 

i don’t think they are Chinese. They are jegs brand heads.

 

I'm going to disagree with this, they love to rev with a decent head/cam, and possibly rod bolts. I believe many thought it was rpm, when it was really cyl pressure/torque killing them. If I were to build another, it would get a S475, and 7500 rpm. Just my 2 cents.

 

what is the easiest way to keep cylinder pressure down???
What causes hightened cylinder pressure???

 

Cylinder pressure is usually boost too early in the curve, combined with timing. Cylinder pressure=torque. You keep them down by bringing in boost after the engines natural peak torque, and/or reducing timing and feeding it back in at the top.

You can also bleed it off with cam selection. Run a bigger cam that favors the top end, you will make less torque, more power. Combine that will convertor stall and the correct size turbo.

 

peeps are finding that if you treat these motors like Lsx stuff they live.
A few guys are making 800hp on 302s.

Low rpm and boost raises cylinder pressure. So keeping the boost and timing held back until XX rpm , then ramp it back in.
For instance. Lsx guys that are pushing sbc lsx will launch at 6000 ish on say 12-15 psi and ramp it back in to peak boost at 40 ish at 7500 rpm and rev to 8600 ish for the shift. But they have oiling system mods and good valvetrain.