stock 302 block, how much power can it take?

ok, i know the rule of thumb is 500hp.
but is that 500 crank or 500 wheels?

what about d.s.s main support system or others like it? do thay work or is it a waist of cash?

i would like to go with a 331 but might boost it down the road. i would rather not pay for a aftermarket block, however i don't whant to have to build a short block twice eather
 
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The main support/girdles help very little Ive heard. some say they are worthless, some say they are great for when you motor blows it will keep all you parts in a nice neat package...lol.....as for 500hp its prolly flywheel...IMO I wouldnt go over 450rwhp, thats kinda on borrowed time. to play it safer and get more life 400-420rwhp and good tune, it should hold up and last a while of beating on it.
 
The nice thing about having an aftermarket block, and some nice rotating assembly, you will never have to worry about breaking anything.

Some may argue that a girdle will not help, but it appears to help a little bit of cap walk, which could be the difference between breaking and not breaking.

One thing is for sure, it will not hurt you.

Some stock blocks have gave way at 400 rwhp, and some have handled over 600 rwhp. I would say typically, I would not go over 450 rwhp personally. Many get in the 500 rwhp range with some creative tuning and cool injection.
 
I would say 450ish at the flywheel is about the max. Some are able to get a bit more but for the most part they are on borrowed time. The block splits from the top down so the girdle won't really help much except keep the caps from walking or keep everything together if it does go. One won't hurt to have one. Try to get a steel one if you can. An AL one will expand at different rates than the block so you want one that will expand at the same rate as the block. The Valley girdles are a joke so don't bother with those.
Kevin
 
my buddy used to run through mustang blocks in his 8 second fox. STOCK as a rock short block, except for SFI flywheel and damper. He would spray 250 at the line and 500 down track (yes, in nitrous) and get 7500 rpm out of them, and he said by about the 8th pass, the block would go. he would run through 10 or so blocks in a decent season of racing. He says the block doesnt just magically break when you go a tick over a certain rpm or hp level. it is the fatigue life that affects when it will break. if you beat it over and over and over again, that is when it will fail. he had a rod come out one time after 4 passes and it hit the track announcer in the leg. he was okay but the driver didn't notice he vented a rod because it went through the cast part of the block, not the oil pan :)

in short, I guess it depends on the driving style and rpm you run more than anything. like you say, better to build it once. or just step up to a 351W, or a sbc :)
 
Driving is is definetly a factor. I know guys that have bolt on 302s and 306s and have split the block with no power adders. They are raced quite a bit and at high RPM. It just usually takes longer with the lower HP smaller displacement motors. So how you drive it and how hard you beat on it are a big factor but when you start getting into the 450-500 hp ranges it is just a matter of time of time before it breaks.
 
at 450-500 id be more worried about my tranny then the engine.

You shouldnt be worrying about if the 500hp is to the wheels or crank though, its just an estimate....it coould blow at 400, it could blow at 700, wheels or crank, pick one.

If your planning on doing a 331, AND planning on adding a supercharger, then I'd also plan on getting a new block.

If you just went with a stroker kit, and got a girdle, and a nice top end, id call it a day with the stock block, and honestly like said before, you dont need more power then that unless your trying to win some drag races.
 
Id say it is the torque that splits the blocks and i would say 550 rwtq - 600 rwtq is about all it will take to split assuming 5500 rpm limit on the motor

If you see alot more rpm it will take considerably less torque to split it

is your block the mexican block or not