Thread: parts selection

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I'm starting to acquire some parts for the Ranchero engine, it will be a 460 stroked to 514 with Edelbrock RPM heads, and Edelbrock Air Gap intake. I am considering running the car on E85 so I can keep the compression up. The car will see very limited street use so the availability of the fuel is really not a concern, I can get it in 55 gal. drums delivered right to the shop. The octane rating is 98.

My question is this. The CFM calculator shows it will want around 725 CFM. The air will come from a cowl induction hood with an air box sealed to the bottom of the hood. Ethanol of course requires larger jetting, but will it also require more CFM??? I used to run a similar engine on methanol with a 750 Dominator, the car occasionally tended to lean out. What Volumetric Efficiency rating should I apply to this set up? The cam will be a roller, max RPM will be in the 6500 range, haven't got the numbers back from Comp on exactly what numbers the cam will be. Headers will be equal length 1 5/8 tubes with a 4" collector.

The other thing I am considering is running an air filter in the back of the cowl induction scoop instead of a bolt on to the carb. Any idea where to get the washable air filter material in bulk???

Thanks for the help.

for the air filter material.... goto a motorcycle shop..... they got tons of it for cheap

Dave, the cfm ingested by the motor is a fixed value determined by displacement and efficiency. Whether you run it on hydrazine or peanut oil makes no difference in the cfm. CFM is what it is based on the parameters I mentioned. The fuel you run, will of course make a difference in how you jet the motor. Ethanol runs most efficiently at around 9:1 air/fuel ratio, methanol at around 6:1 and gasoline at around 12.5:1.

Thanks Tech. Guess I'll stick with the 750 Dominator carb. I've seen some of the new air/fuel ratio gauges that are powered by 12 volt electrical. Might be easier on ethanol than trying to get an accurate plug reading.