[j2000_guy]

ok plan on doing H/C swap. and i wanted to S/C with a procharger. but ive heard that stock blocks can only handle like 450-500hp. Wouldnt a setup like that be right around that 450-500hp? so i would risk losing my block or what?

[stang94]

I think if you get a proper tune, you should be fine.

[Bullitt95]

The strength of the production 5.0 block has nothing to do with the tune. I've read various figures about the HP limit of the stock block but it does seem to be about 550 crank HP. Above that, you risk cracking the block along the lifter valley and I've even seen pics where the main webs completely separated from the block.
You can strengthen it by adding a main bearing cap girdle that's secured with main cap studs, and add further strength to the lifter valley with a lifter valley girdle kit. You can buy both kits from Jegs.

[stang94]

Originally Posted by Bullitt95 The strength of the production 5.0 block has nothing to do with the tune. I've read various figures about the HP limit of the stock block but it does seem to be about 550 crank HP. Above that, you risk cracking the block along the lifter valley and I've even seen pics where the main webs completely separated from the block. You can strengthen it by adding a main bearing cap girdle that's secured with main cap studs, and add further strength to the lifter valley with a lifter valley girdle kit. You can buy both kits from Jegs.

So you can trow in some nitrous, supercharged, H/C/I swap, make about 500HP (crank) and drive all day long will not do anything to the stock block?

I believe someone on here crack a stock 302 block with less hp than that.

[Bullitt95]

With the block strengthening measures that I mentioned, you could go as far as a supercharged HCI swap set up. Adding nitrous to that would take it over the top and crack the block. Limit rpm to 6250.

[rj95svt]

some people split the block with 400 to 450 hp while others get lucky and have survived with 550rwhp. It seems as though there is no way to tell how long it will last at those levels. If you don't beat on the motor and keep the rev's at or below 6000 it might last for years or might last for one 1/4 mile pass. There's no real way to know. As far as girdle's go the general consensous is the main girdle's won't stop a block from spliting but I don't know anything about valley girdles. Most people say it's just a gimick but I don't know.

[rj95svt]

sorry double post.

[j2000_guy]

ok so ive talked to a few other ppl and i think ill be safe with H/C and S/C. so next Q is my block would have 112K on it, should i rebuild the lower? i REALLY dont want to do that.

[rj95svt]

I'm curious. Have you ever run your car at the track? If so what kind of times did you run? My car Is very close to yours as far as mods go. The only difference being headers. I have not got a chance to take mine to the track yet.
Do a compression test and leakdown test to ensure that your engine is in good shape and just keep your rev's down and keep your tune conservative and who knows your stock shortblock might last indeffinatly!

[95opal]

The truth is