[Dragncar]

E-85 is finally available around here and pretty cheap.
Currently I am running 95.6 octane and no issues. I started out with 100 octane and went down in steps to the 95.6 octane.
The next step is going down to 94.2 octane. If all is right I could try straight all gas 92 octane but I do not know if its worth it.

This E-85 has got me thinking, is there a benefit to it ? Its cheap, plenty of octane and I would have to re work a couple of carbs.
I was planning on settling down with the 94.2 octane and be done with it. It would be 4.5 gallons of 92 octane mixed with 1/2 gallon of 114 octane but its almost double the cost of the E-85.

[charlie66]

It's cheaper yes, But the real benefit is it gives cooler intake temps. On a 90-degree day my intake is frosting up sometimes or just balling up with real cold moisture. It's not as volatile and burns slower more like a race gas does. Thats why you need more because it doesn't burn as hot, so more is needed to equal the same btu's. It's worth it to me. JMO

[bluegoat65]

I like it. To me though its not consistent. That's why I just use it in my street car. In my area it will start out at 85% or less but as the summer goes it will rise. I have tested it in August and the blend will be in the mid 90s% range. Its heavy oxygenated and likes moisture. If you let it sit, as it evaps it will leave a sugar crust that plugs everything up in the carb. Just need to keep it moving or sealed. If I have the number right, it will support up to 10.5 Dynamic compression. If your using a carb you need around 30% more area to meet the need of your combination as when it was on gas. Just my experience with it.

[Stan Weiss]

Originally Posted by charlie66

It's cheaper yes, But the real benefit is it gives cooler intake temps. On a 90-degree day my intake is frosting up sometimes or just balling up with real cold moisture. It's not as volatile and burns slower more like a race gas does. Thats why you need more because it doesn't burn as hot, so more is needed to equal the same btu's. It's worth it to me. JMO

What this means is you will need to burn more E-85 than gas, and so will need to look at cost of a gallon of gas verses 1.x gallons of E-85.

Stan

[charlie66]

Originally Posted by Stan Weiss

What this means is you will need to burn more E-85 than gas, and so will need to look at cost of a gallon of gas verses 1.x gallons of E-85.

Stan

Yes, but with my situation (turbo 40 psi) it's cheaper than race gas by far.

I use it on the street for driving around it's not so bad.

[charlie66]

I don't know what gas prices are other than here but e85 is 1.98 here. Not too bad imo.

[Stan Weiss]

Originally Posted by Dragncar

E-85 is finally available around here and pretty cheap.
Currently I am running 95.6 octane and no issues. I started out with 100 octane and went down in steps to the 95.6 octane.
The next step is going down to 94.2 octane. If all is right I could try straight all gas 92 octane but I do not know if its worth it.

This E-85 has got me thinking, is there a benefit to it ? Its cheap, plenty of octane and I would have to re work a couple of carbs.
I was planning on settling down with the 94.2 octane and be done with it. It would be 4.5 gallons of 92 octane mixed with 1/2 gallon of 114 octane but its almost double the cost of the E-85.

Originally Posted by charlie66

Yes, but with my situation (turbo 40 psi) it's cheaper than race gas by far.

I use it on the street for driving around it's not so bad.

Yes, I can see it for you, but was pointing out to Dragncar / Troy that there might not be as much savings as he thinks.

Stan

[charlie66]

Originally Posted by Stan Weiss

Yes, I can see it for you, but was pointing out to Dragncar / Troy that there might not be as much savings as he thinks.

Stan

I kind of feel that it might be cheaper for him to buy because the e85 usually is 1.00 or more cheaper than 92. 100 octane is 16.00 a gallon here. idk what it is over there. He will be able to add more timing as well if he needs to .. Plus, the hassle of mixing fuel, I know I wouldn't like to do that all the time myself.

[slowbird]

Imo from what I have seen there is little to no advantage running it in an na engine unless you push the compression up. In an engine that can run regular pump (91-92 ocrane) there might actually be a performance loss with e85

[performerrpm]

i plan to run e85 in my blower motor....problem with e85 is one day its available, next its not....kum n go by me had it for years...now maverik took over and got rid of that stores e85...now i will have to go the next town over...but its not like im daily driving it so its not so bad

[Dragncar]

Originally Posted by slowbird

Imo from what I have seen there is little to no advantage running it in an na engine unless you push the compression up. In an engine that can run regular pump (91-92 ocrane) there might actually be a performance loss with e85

Thats what I was wondering right there. If I have to deal with any buildup of gunk in the carb and a performance loss it might not be worth it.
Less consistent, its a bracket car.
It does not get hot where I live. 70-75 on the beach is a hot day around here.
If E-85 was available when I finished the engine I might have bumped up the CR.

[mysticmissle]

not worth buying a new carb for this application in my opinion.

[blueghoast]

11:5:1 should be pump friendly. mine is 11:5:1 I run pump gas all the time.
Only time I use race gas is when I'm spraying it.
Try it I think you'll be surprised.

GT

[Dragncar]

Originally Posted by blueghoast

11:5:1 should be pump friendly. mine is 11:5:1 I run pump gas all the time.
Only time I use race gas is when I'm spraying it.
Try it I think you'll be surprised.

GT

Not sure if I want to trust 20K to CA 91.
I can get all gas 92. Thats about as low as I want to go.
1/2 gallon of 114 and 4 1/2 galls of CA 91 and get 93.3 octane. Might end up there.
If I had a dyno close by I would know exactly what kind of fuel was best. But I don't.
I am going to be careful with this engine.
If I get around to doing the IA engine with the parts I still have it would come in at 10.8 CR and would run on 91 all day long. And I could beat on that thing.

[charlie66]

I used 92 with a 461ci at 11.3.1 With no issues. Did that with that motor for 14 years and never had a problem. it ran 9.90's. But you better be right on with the tune. Drove it on the street all the time too. E85 is much cheaper and will make your car run a bit cooler.
As long as you keep the air out of the lines it won't really corrode. Never had an issue with that. I just checked inside the bowls once in a while. Keep the fuel in it My car has been stored all winter with full bowls, and I'm not worried at all..

[Dragncar]

The guys at Performance Carb who built 2 carbs for me told me there is nothing to gain @ 11.5-1 CR. There is a learning curve with tuning and your carb once set up for E-85 can not go back to gas. Passages need opened up for the alcohol.
Cost 400$ to have your carb redone for E-85.
Now if I was 13-14 to 1 its a different story. Well worth it vs the cost of race gas.

[Jay S]

I think a mix of E85 with regular gas would be ok and get you to the octane goal. The final mix would probably be like E30. I don’t think the carb would need any mods other than stepping up the mixture a bit.

[blueghoast]

Originally Posted by Dragncar

The guys at Performance Carb who built 2 carbs for me told me there is nothing to gain @ 11.5-1 CR. There is a learning curve with tuning and your carb once set up for E-85 can not go back to gas. Passages need opened up for the alcohol.
Cost 400$ to have your carb redone for E-85.
Now if I was 13-14 to 1 its a different story. Well worth it vs the cost of race gas.

I have two motors one is 10:65 and the other is 11:50 and I don't really
see a diff between them either. So that little bit in compression I don't
think it really matters unless your going for a world record or something
like that. I just play around on the street mostly.

GT

[GOAT8U2]

What's the rule like every 1 solid point in compression is roughly 3% power increase on the combo so 11.5 (I'm here too) is just you maxing out the pump gas power. 550tq x .03 is 16tq gain so not much felt on a 4000lb car but it's there and free so to say.

[Stan Weiss]

Originally Posted by GOAT8U2

What's the rule like every 1 solid point in compression is roughly 3% power increase on the combo so 11.5 (I'm here too) is just you maxing out the pump gas power. 550tq x .03 is 16tq gain so not much felt on a 4000lb car but it's there and free so to say.

The increase from a change in CR is not linear. What that means is the lower the CR the more you will see from 1 point increase in CR. So going from 8 to 9 will give a greater increase than 11.5 to 12.5.

Stan