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Discussion Starter #1
Im wanting to build a 12.5:1 393 stroker and what im wondering is will a 351w block handle that kind of horsepower? Im going to be using AFR 205 heads and an isky solid roller camshaft. Not sure what cam yet. Looking to shift somewhere around 6500. I may possibly being squeezing a 125hp kit on this motor too from time to time. What all would I have to do to get a factory 351w block up to par for this kind of punishment. Thanx alot
 

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A buddy of mine pushed a 79' block that was stroked out to 426ci with a cut down 400M crank and Chrysler rods to a 5.92 @ 121 in the 1/8 on two stages of nitrous... and did so for two years before selling it and building a Motorsport block.

It had a cheap Herbert 252/262 solid roller and was shifted at 6-6.5k. The car weighed 3000lb w/driver and used a C4 w/brake and a 3.73 gear in the 8.8 rear. The car was NOT tubbed, and only had 11.2 compression. The block was not filled and had a homemade girdle.

They are quite strong...
 

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Should handle 750HP with just ARP main studs. '69-'76 blocks are the strongest('69-'71 being best) and will hold up to more than what people have been brainwashed to think(not talking about you Chilly
). Cap walk is not a problem with 351Ws and the main caps are very strong. They use the same size main bolts/studs as a 429/460 except for a different length and have much thicker cylinder walls than a 289/early 302. Main webbing is beefy also. Don't worry about the block. It will hold with just ARP main studs. Guirdle is just an extra piece of mind and precautionary measure. This is not a weak 289/302/351C block, it's a much stronger peice.

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<font size=-1>[ This Message was edited by: 89 coupe on 4/25/02 4:32am ]</font>
 

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I have heard that a 302, even the weak-webbed later blocks can handle 500HP. With that said, look at the difference in the main caps on the 351W. Not to mention the size of the crank's mains. I would safely bet that 750HP is not a problem if you use top quality fasteners.

I am not that experienced with racing apps, but I have never seen a broken 351W unless a rod bolt broke or some serious internal problem ocurred first. Most failures are rods, timing chains (valve-piston crash), and bolts breaking. The block is a nice piece of metal. The 351W is the reason I am a Ford nut. Have been for years.
 

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And if you're super concerned, the newest article on the main page discusses beefed up aftermarket blocks.
 

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Discussion Starter #7
I would really rather run a factory block beings i can get those pretty darn cheap compared to aftermarket which will be at least 1500. Ive heard of 302 blocks not being very strong in the webbing thats why I was concerned about a 351w block too i never knew they were so much stronger. I think ill just run arp studs and a trick flow stud girdle. Sound good everyone? Thanx for all the help so far.
 

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Sounds good to me. You can use more nitrous without worry also. a NOS Big Shot system would work well(350HP) as long as you got ARP main bolts or main studs. a main guirdle isn't necessary but people knowing they have one on there seems to let them try for more power with more RPMs or nitrous but not using a guirdle can handle it too. Use the stock block with confidence and don't worry about the block not being strong enough. Have fun with what looks like a good combo but it can handle more nitrous than what you want to use.
 

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And you can take the cast Scat 3.85" stroke crank and stock block to 7800-8000RPM shift points on the 392 stroker if balanced without a problem too. Don't limit the RPMs for fear of the stock block, it can handle it unless you just prefer 6500RPM limit for mild everyday street use.
 
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