I bought a gmpp 350 block. It is a bolt main and has never been used. It cam brand new from gm. Anyways gm states is rated for 600hp. I am going to be doing around 480-500 flywheel and i wanted to spray on top of that. Is there a difference between what its rated at and rating it for spray?

like is it rated for 600 na hp

 

no, lol....horsepower is horsepower...no matter witch way you cut it


btw....600hp is a **** loud of power...i would never say "only 600hp" lol

 

Use ARP head and main stud kits instead of bolts. This should help it hold together better. If its bored .030 then I would think that some of the rotating assembly would let go first.

 

Lol i know 600hp is a lot. however. I will be making 480-500hp at the fly like i said. I was really wanting to spray a 150 shot on top of that.

the rotating assembly is rated for 850hp. Its completely forged internals and arp bolts consume the whole motor top to bottom.

 

You'll be fine. It is highly underrated to cover their A$$. Also hp is NOT hp. An engine that makes 600 hp N/A at 7500 rpms is going to be much harder on the block than a supercharged 600 hp motor at 6000 rpms.

You didnt say what bolt block it was, I'm assuming four, many people have taken them above 800hp without issue.

You'll be fine, you could even do a 250 shot.

Have fun.

 

450-500HP on a 350 block, i'm guessing a high revving 383? What about a short fill for stiffness?
I'd use ARP studs (not bolts) for the main caps. What caps, nodular iron?

 

I bought the arp head stud kit. The motor was built by M&R and the whole internals of the bottom end except the block was built for 850hp
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That was exactly what i thought. I want low 10's and thats why im pushing a 150 shot. lol

Also the only way the motor block will; break is by too much pressure right? Or a piston through the wall. However all things being well. It could only crack right?

 

Like he said, you'll be fine. What are you doing to get that much horsepower? That's alot for a N/A 350.

 

I'm not an expert on block failure, but generally when a sbc is pushed, the bottom end moves around. When the bottom end moves, the bearings move, and are no longer aligned. They wear prematurely and you lose oil pressure.

My engine builder runs a 500hp 383 with nitrous to get into the low 10s. Been doing it for years. He's not running it this year because he says its about time for a rebuild and look over. I think its been about 5 years.

YOUR TUNE IS MOST IMPORTANT!! Stuff will break for sure, no matter what parts your have, if your tune is bad. Nitrous kills without enough fuel. Make sure your fuel system is correct.

If you don't have the block machined yet, you could do a short fill (hardblok) like sonix said. It strengthens the bottom end.

 

Its 200cc heads from dart big cam with 1.6 rockers for a little more lift rpm air gap intake 750 carb and a 383. I saw similar combos go about 500fly hp.

I have a performabuilt transmission and im doing full suspension now then im off to the rear axle. but ya im gonna be gettin no mpg. lol i love it

Its carbed but im still going to get a professional tune. Here in central florida they got good tuners.

my only worry is my holley blue top fuel pump. Im gonna get a separate fuel pump and fuel cell for the nitrous though

 

Lol, yea, when I go for a 5 min burn, I use a gallon of gas.