Ford Mustang Forum - View Single Post - I wonder if 1000 hp is possible with the 3.7?
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post #42 of (permalink) Old 09-25-2013
Smurf stang
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Originally Posted by Intense View Post
I don't know about any build.

To make hp, which is a function of torque and rpm, you're going to either have CYL pressure or lower cyl pressure at a higher rpm.

This little 3.7's block was not designed for a 330% power level. It is NOT rigid enough. First fault at high power's aluminum, it flexs more than cast iron. IE look at the GM LSX block and read up on it. It's not aluminum. It took til '13 for the Shelby to have a purpose built aluminum block....a very powerful "only" 660+ hp.

Aluminum is not rigid enough. The block will move around a lot internally and will have to be setup really loose on run a while if you're lucky. It's not a matter of if it will blow up, it's when. It's difficult to maintain main and rod bearing clearances when even the side bolted main caps start moving and walking around. If it would run long enough. Take the caps off and take a look at them. You'll see signs of abrasion. That's called "cap walk". hold that cyl pressure...with a block moving around that much, do you think those floating cyl liners aren't moving around too...and only 4 bolts per cyl on top of that? It's an economical lightweight block.

As to rpms....with a displacement of're not going to see enough rpm to get there with a factory based valvetrain geometry.

IF I were insistent on the goal of 1000hp at the crank...I'd use a 3.5 block which would be a better/stronger starting point with a stiffer deck. If a builder tells you otherwise, they want your money.

Realistically and reliably, I'd shoot for an attainable goal that will live a while to at least get some smiles out of the engine.
Tell that to the GTR guys with their stock aluminum block in their little 3.8's making 1,000 hp.

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1989 Sonic Blue Mustang LX Coupe, 349 ci,
392 rwhp 424 rwtq....Mustang Dyno
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