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yfinn6 wrote:

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Track car or drag car? What gears were you putting into it?

Dirt car.  He ran in Eagle River on Tuesday night and had 6.50's in it.  Had to take those out and put a set of 5.67's back in for a half mile.  

There are a few other things to take into consideration here. 5.67's are pretty common and not insane at all for this application. 6.50's on the Eagle River track were about right...could've stepped down a hair or two but it worked. When the sweet spot in your HP curve is between 5,000 and 7,000 RPM's you need something that's going to get up quick and max out right around the time you hit the brakes. I don't think you'll consistently be twisting a street motor around 7,000. When my brother raced a dirt late model in the 90's we were consistently turning that thing between 7700 and 8300. Guys now are pushing them even further....but....you're turning some pretty lightweight stuff throughout the drive train. Basic in-out boxes for transmissions, aluminum gears, lightweight stuff inside the engine, and cars that are around 2200 pounds. Your rims are right around 10 pounds each. Compare that to a street car. As a general rule if you eliminate one pound of rotating weight it is like elimination 10 pounds off of your total non rotating weight in that car.

Your engines also are not the types of things you'd be able to piece together through your local automotive supply store. One local guy who has run Fords for years got an engine from Roush-Yates this spring. It's a 410 at 14:1 compression that kicks out in excess of 850 hp with over 600 pounds of torque. The price tag on that thing is probably around 40k.