Will a stock block handle 600 hp?

Rick 91GT said:

A stock block is a stock block, they are weak up through the center of the mains and lifter valley. Even a properly prepped "Which I can only assume is a blue printed block, which includes relieving all the stress points, which I do as well" will split right up the middle.

Here's some food for thought from first hand knowledge, stock 302 block, half filled with Hardblok, spinning 8000rpm (built for the rpm with custom parts, lightweight internals, etc, etc...), around 425RWHP split right at the #2 main, car was race only.

Now back to the N2O, will it take a 200-300 shot, sure...how long will it take that stress and abuse, 9 out of 10 times not long.

If you are building a motor that you want to spray or boost heavily planning on over 550HP a upgraded block is a very, very smart decision. A DART Sportsman is around $1750, a DART Iron Eagle is around $2000.

Sticking a 4340 assembly in a stock block is a waste of money unless you plan to eventually put the same internals in a race block. Most of the aftermarket cast assemblies will take 650+hp which is about the limit of most stock blocks.

A lot of guys are making 700HP through a 69-74 351W with no issues, I have seen numbers as high as 900HP, but again then will eventually split, especially if you get greedy. The later model 351W blocks can split just like a 302, onefast split his with 650RWHP.

Thanks for the kind words Nate, you should see that NOS blanket tomorrow.

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need a fast car said:

Yes you can do that with the right internals. I deffinately wouldn't go or try to go past 700 on a stock block. I'm going to get a probullet and push a max of 650 on it, with proper tuning of corse. also I always wondered how much does a 351 block handle? just curious.

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