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scottracer
07-23-2012, 04:54 PM
I have a steel block motor with AFR heads the motor is about 14 to 1 compression with a roller cam in it, and on racing gas is about 700 horse, Any of you engine guys know if I can switch to E-85 fuel , will the fuel support the compression with out burning the pistons, wil the horse power be more or less? And what size Carb should I use and what jet size , Is the quick fuels E-85 Carb big enough, Any information out there... Thanks

gatorade
07-25-2012, 08:29 AM
i had this conversation with Mike Dargie from Dargie race engines and i have to say he was an awesome guy to talk to: i'll try and illustrate it to you like he illustrated it to me.

look at it like this

50 nights a year running vp late model plus will cost you 3500 and prolly 3100 for VP c12
50 nights a year running E-85 will cost you 2000 (cheaper but you burn more) plus the carb cost lets just say that 500 dollars cuz you found a smokin deal... Is that a 1000 risk really worth it?

By the descripition of your motor it soulds like it should have plenty of snort, just bite the bullet and keep the best stuff possible in it and eliminate the variable!

JMO, best of luck
JR

dualdj1
07-25-2012, 09:18 AM
Ethanol is a good fuel. We ran it in our mod when it first came out. Consumption is between that of gas and methanol. It's not near as corrosive as meth though. It does run cooler like meth, so would be advantageous if your car runs hot. No prob on handling that level of compression.

I saw one place say you need about 30% more fuel delivery (jetting) over gas. Don't know for sure; we started with an alchy carb on the mod, and had to jet back several times to get it right, but it still ended up more rich than gas.

So key points:
-- More consumption than gas = more weight change in long races.
-- Burns significantly cooler than gas

dirty white boy
07-25-2012, 01:11 PM
at 14:1 compression,..id put lest 110 race gas in it!

Egoracing
07-25-2012, 01:28 PM
14:1 is to high for pump E85

scottracer
07-25-2012, 01:50 PM
Thanks guys, we have just been toying with the idea, and sounds like we need to stay where we are and run the racing gas,, I appreciate the help

dirty white boy
07-25-2012, 02:27 PM
Thanks guys, we have just been toying with the idea, and sounds like we need to stay where we are and run the racing gas,, I appreciate the help

at that ratio,..try sumpin less an it might make flattops outta them domes,..bigger the monster the better ya gotta feed it...

MasterSbilt_Racer
07-25-2012, 03:13 PM
I have heard of it working just fine, but you would not have the margin for error that a higher octane race gas would give you.

dualdj1
07-26-2012, 09:02 AM
I have heard of it working just fine, but you would not have the margin for error that a higher octane race gas would give you.

That was my thought as well. But, we actually ran E95 when we used ethanol on the mod, so can't say for sure.

Again should be safe, but is possible you'd have to run less timing than you would on gas.

Remember too, that ethanol burns cooler. Lower temp at equal octane = less change of spark knock.