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Author Topic:   Alcohol or Race Gas?
posted January 26, 2004 10:04 AM
Id prob pick one and stick with it. The different rates of burnoff could affect how youset the car up and then you would spend time chasing that down ea time you changed motors. I think the gas would give you smoother power, not the sudden burst like alky sometimes will. You just have to make sure you can keep it cool and not detonate on it.

posted January 26, 2004 09:57 PM
would depend on the octane level (rating of the racing gas.
an octane of 100 is pretty much on the limit with 13:1, and your tune will have to be "spot on", no room for error.
alcohol won't do much with less than 12:1.
i've never had anything to do with gasoline with an octane guaranteed to be over 100 so i have no idea. but i do believe it available.
i would talk to the gas company and/or a reputable engine builder (maybe steve can help).

posted January 26, 2004 11:25 PM
We build our dirt late model gas engines at 15.5:1 , and our alky engines at 15.5:1 On gas this compression ratio requires very good fuel. We primarily use VP's Late Model Plus with these engines. But I do have some customers with different fuel deals who run 114 and 116 octane, depending on the brand. All in all, the VP has produced the best result's. Unfortunately it's also just about the most expensive.

At 13.2:1 your engine will run fine on alky. It will produce slightly more torque, and roughly the same HP as gas with the same cam. Cam selection is critical for alky engines however, and is completely different than a gas cam. You only really start seeing big number increases with the correct alky grind and a compression ratio up in the 14 to 15's.


Hendren Racing Engines
Rutherfordton , NC
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