im working on getting all the parts for a big number hp supercharged 383 and it dawned on me that im not so sure if a stock block can take so much hp...its a gm goodwrench block...12499529 i believe thats the casting number...im looking for around 6-700hp at the flywheel...but if it cant handle that much i may just tune it down some...im puting the mp122 magnacharger on and was thinking bout running 10psi...but i could drop it down to say 8 and that would lower the hp quite a bit...aftermarket blocks are not cheap so if it cant handle those numbers ill just tune it down till im ready for more hp then ill get an aftermarket block...this is mainly a street/show car but will see some track

 

Depends on what dyno, on a Superflow 600hp then they nornally
Crack in half right down the lifter gallery. Don't get me wrong they
will live for alittle while I just can't say 1 week, 1 month, 1 year...

If your talking a dynojet or mustang dyno just add 15 to 20%.

 

about the only thing you can really do is fill the block...i've seen lifter valley braces advertised but i don't know anyone who has ever used one.

 

Mine dynoed 633rwhp two seasons ago, and made another 40 or so this past season. No problems that I'm aware of in those two years with the block, even after shoving head gaskets and melting a bit of a piston from a foolish attempt toward the end of the 2007 season. BTW, 2007 I was using 10psi and this past season was 15psi.

I'll be sure to post up if any problems come about while attempting to use this 1550hp turbo I'm putting on now.

 

I doubt there's any specific number as to when they will crack. It depends on how much and the type of stress is put upon it. Typically when you start making high HP small blocks, an aftermarket block is a necessity. The aftermarket blocks are not indestructible but they'll take a lot more abuse than a factory block. Getting 700HP on a dyno and actually using 700HP on the street are 2 different things. Street driving it, you'll never fully use the potential of the engine.

I paid $3000 for a bare Dart big M block. Didn't include freeze plugs or cam bearings and needed to be bored and honed to the final size. With the bigger heads I'm putting on my engine, top to bottom, the engine is now worth at least $30,000 for parts and labor. HP costs money. Reliability costs even more.

 

Your trying to tell us you have a 1500 hp small block and are still using a stock block??

 

Not exactly what I'm trying to say. I did max out the blower I previously had on it that was rated at 900fwhp, but I think I got more out of it than that rating. I got this turbo with the idea of being able to go up to the 25-30psi range, but I'm starting off with the 10psi spring in the wastegate and going from there. My trans. builder said the trans. he built me is good up to 1250fwhp, which would make an 8.9-9.0 run, so I plan on running in that area. The turbo should have the capability to make the car do an 8.40 or so, granted the rest of the parts can also.

 

yeah i get what yall saying...at the wheels i would like to see 500whp...600 be nice too lol...this car is just my toy...dont worry ill get the full potential out of it...i just wanted to be sure if my block can handle it or not...right now i think i just ganna go with it...and if it does crack ill just upgrade to an aftermarket block later on...and rebuild the motor...thx for yalls advice