I looked into a while back but E85 is not available here in NJ. 
Total timing? When using E85 in a built motor
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Total timing? When using E85 in a built motor
Just wanted to know about how high to go using afr 235 cc heads on a 421 ci solid roller motor
E85 is new to me 13.2 cr 950 cfm alky carb 2 inch spread port headers open with 14 inch collectors drag racing only vette about 2800 pounds
E85 is new to me 13.2 cr 950 cfm alky carb 2 inch spread port headers open with 14 inch collectors drag racing only vette about 2800 pounds
Thread Starter
Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
So depending upon which write up you believe e85 might be around 105 octane. So we are going to do some runs up around 38 to 40 degrees and then play with up or down and watch the mph
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Oh yeah I forgot to say that where the car runs is 1/8th mile and for the last two years runs about 106 mph with a th400 4500 trans brake
So the only change was e85 and alky carb
So the only change was e85 and alky carb
Melting Slicks
Joined: Mar 2008
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From: Spring Park MN
Actually even though the octane is higher than pump gas, ethanol lights off and burns faster than gas, so total timing shouldn't change much, unless it was backed off for insufficient octane. If he was already running race gas, which it sound like he probably was, he shouldn't need much changes on timing. I would still try of course to find what timing gives the best trap speed after getting the AFR right. I would use a wideband as ethanol will not show as big of changes in trap speed during jetting. It is more forgiving in that way.
On the street you can bring in the total timing a little earlier than pump gas. Drag racing only he probably has the distributor locked at full advance.
Mike
On the street you can bring in the total timing a little earlier than pump gas. Drag racing only he probably has the distributor locked at full advance.
Mike
Last edited by v2racing; Apr 4, 2017 at 04:09 PM.
Melting Slicks
Joined: Mar 2008
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From: Spring Park MN
One more thing, get a fuel tester so you know what percentage the ethanol to gas is. Need to know this if you want to have consistency. Some people buy E85 at the pump and buy 5 gallon cans of E98 to correct the percentage. At the pump it can vary from 70% to 87%. On the street you wouldn't probably notice, but racing it will show up.
Mike
Mike
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From: Waterford CT
Actually even though the octane is higher than pump gas, ethanol lights off and burns faster than gas, so total timing shouldn't change much, unless it was backed off for insufficient octane. If he was already running race gas, which it sound like he probably was, he shouldn't need much changes on timing. I would still try of course to find what timing gives the best trap speed after getting the AFR right. I would use a wideband as ethanol will not show as big of changes in trap speed during jetting. It is more forgiving in that way.
On the street you can bring in the total timing a little earlier than pump gas. Drag racing only he probably has the distributor locked at full advance.
Mike
On the street you can bring in the total timing a little earlier than pump gas. Drag racing only he probably has the distributor locked at full advance.
Mike
Would the AFR be the same with E85 as it would for gas?
You have to burn much more E85 than gas to get the same energy.
I am thinking about E85 with my car, which I am converting to EFI. I figured the world needs a low emission L88 motored car about now.
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Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
If you use an AFR meter that only reads AFR for gas, you set the AFR for ethanol at the same reading as you would for gas, 14.2 to 14.7 cruise, 12.5 to 13.2 best power. Although I would stay closer to the rich side of the best power.
If you can read in lambda, set cruise between .97 to 1 lambda. Best power .85 to .9 lambda. Again, stay to the rich side of best power.
For boosted applications the best power readings are set richer, .74 lambda and 10.8 gas AFR, 7.2 ethanol AFR.
Mike
Last edited by v2racing; Apr 6, 2017 at 05:46 PM.
Thread Starter
Team Owner
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I took a test drive on a country road and even with the timing at 38 it has some get up and go. It has a recourved mallory unilite with about 18 mechanical.
I just don't think that my buddy optimized anything from day one. They were trying to set the timing by the initial. So they might have had 30 degrees on race gas. The 10 inch slicks have about 8 inches of use in the middle and he said that he was running about 15 psi It should be sub 10 psi. The alternator was always spitting belts and they didn't have enough brain power to understand that on a 7600 shift point that you might need to change pulley sizes.
Out of state and I came up here to sort it out before the season..... what a head ache and spotty weather now
I just don't think that my buddy optimized anything from day one. They were trying to set the timing by the initial. So they might have had 30 degrees on race gas. The 10 inch slicks have about 8 inches of use in the middle and he said that he was running about 15 psi It should be sub 10 psi. The alternator was always spitting belts and they didn't have enough brain power to understand that on a 7600 shift point that you might need to change pulley sizes.
Out of state and I came up here to sort it out before the season..... what a head ache and spotty weather now
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
I took a test drive on a country road and even with the timing at 38 it has some get up and go. It has a recourved mallory unilite with about 18 mechanical.
I just don't think that my buddy optimized anything from day one. They were trying to set the timing by the initial. So they might have had 30 degrees on race gas. The 10 inch slicks have about 8 inches of use in the middle and he said that he was running about 15 psi It should be sub 10 psi. The alternator was always spitting belts and they didn't have enough brain power to understand that on a 7600 shift point that you might need to change pulley sizes.
Out of state and I came up here to sort it out before the season..... what a head ache and spotty weather now
I just don't think that my buddy optimized anything from day one. They were trying to set the timing by the initial. So they might have had 30 degrees on race gas. The 10 inch slicks have about 8 inches of use in the middle and he said that he was running about 15 psi It should be sub 10 psi. The alternator was always spitting belts and they didn't have enough brain power to understand that on a 7600 shift point that you might need to change pulley sizes.
Out of state and I came up here to sort it out before the season..... what a head ache and spotty weather now
When I used to hire out as a crew chief it was often a challenge. Some guys setup was so far out in left field I'd have to change almost everything about their tune up and setup. I had one guy who was the normal crew chief say to me " I thought you were only supposed to make one change at a time." I told him you are, but if I'm going to make this thing competitive this weekend, I need to change everything.
Mike
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
My Top Fuel bike I only ran 4 to 4.5 psi.
Mike
Thread Starter
Team Owner
Joined: Apr 1999
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
A lot of guys get nervous about running the low pressures in slicks because they feel a lot squirlier on the top end. I'd put about 9 psi in to start and tell him not to oversteer when it moves around on top, just kind of ride it out instead of fighting and making it worse.
My Top Fuel bike I only ran 4 to 4.5 psi.
Mike
My Top Fuel bike I only ran 4 to 4.5 psi.
Mike
Mike, I know......... I've owned S/C dragsters, CE dragsters,Driven 8.90 camaro, my poor vette. nothing as fast as you with a turbo bike only doing 7.60's.
In my vette I only used about 8.2 8.5 pounds with goodyear 10X28's
Where he lives is an 1/8th mile I'm not sure how 106mph in the 1/8th ends up in the 1/4 mile
I was just at the Vegas NHRA and it is interesting that they have the nitro Harleys running about 220 + or - with non supercharged motors don't quote me on the speed
hey I'm doing good. Recently retired and only work on things I want to
Last edited by gkull; Apr 6, 2017 at 08:47 PM.
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
Mike, I know......... I've owned S/C dragsters, CE dragsters,Driven 8.90 camaro, my poor vette. nothing as fast as you with a turbo bike only doing 7.60's.
In my vette I only used about 8.2 8.5 pounds with goodyear 10X28's
Where he lives is an 1/8th mile I'm not sure how 106mph in the 1/8th ends up in the 1/4 mile
I was just at the Vegas NHRA and it is interesting that they have the nitro Harleys running about 220 + or - with non supercharged motors don't quote me on the speed
hey I'm doing good. Recently retired and only work on things I want to
In my vette I only used about 8.2 8.5 pounds with goodyear 10X28's
Where he lives is an 1/8th mile I'm not sure how 106mph in the 1/8th ends up in the 1/4 mile
I was just at the Vegas NHRA and it is interesting that they have the nitro Harleys running about 220 + or - with non supercharged motors don't quote me on the speed
hey I'm doing good. Recently retired and only work on things I want to
The Top Fuel Harley's fastest top speeds are over 230, but it doesn't happen often. They have been sub 6.2, but that hasn't happened in a while either. 6.20's are common but not consistent. They have some work to do yet.
Mike