I had always wondered just how much gain in HP is possible with E85 over petrol. Most E85 converts immediately turn up the wick, and for good reason. I ran my car at 28psi for the first two years after going to E85 in the summer of 2008. Now with 90K miles on the odometer, I decided a wee bit of mechanical empathy was in order.

So, I recently had a fresh 91 octane 20psi eTune and then followed that up with an E85 eTune at the same boost level. This is on a lightly modded EVO VIII. My mod list is below the graph. Results are uncorrected at 2,500 feet elevation.

My as yet unproven theory is, that by keeping the boost at the factory level, I'm allowing the turbo to operate much closer to its peak efficiency. If I'm full o'crap, feel free to set me straight.







Mods are:
BR cone filter
BR SS MAF pipe
Hallman MBC @ 20psi
IX DV/BOV
Helix down pipe
Helix test pipe
Greddy EVO2 cat-back (modified to 3”)
HKS 264/264 cams
Nisei LICP
Walbro 255Lph fuel pump
IX turbo
PPI ported ex manifold
'eBay' SS O2 housing
ETS 3” FMIC
RC 1,000cc injectors
Tephra v7 Universal ROM w/dual maps
E85 and 91 tunes by Jay at Boosted Tuning

 

Gains look great up top especially on such small cams! Did you keep peak tq timing down on purpose? You plan on turning up the boost on e85 or you just going to leave it like that?

 

Well, Jay did the actual tunning..., but there was no intent to hold back anything. The goal was to squeeze as much safe HP and TRQ as possible out of both tunes. This is NOT a weak 91 tune compared to a more robust E85 tune.

 

THats not what i was trying to say. no disrespect meant. i was just expecting a little more torque out of the E85 thats all. sorry didnt mean to offend you. just was asking a question.

 

No offense taken; sorry if I came across that way.

Here is some of the back-story, if you have trouble sleeping at night.

https://www.evolutionm.net/forums/al...witch-e85.html

https://www.evolutionm.net/forums/al...-e85-tune.html

For now I'm just staying on the 20psi E85 tune, although Jay also did a fresh 25psi E85 tune as well.

 

No trouble sleeping. I was just curious. I read the back story and those E85 numbers were amazing!! any chance you have the graphs for that 25 psi tune on E85? Car looks like a lot of fun! Enjoy it!

 

cool i've been wanting to see that comparison for awhile... I cant believe how much of a difference there is!

 

E85 is the way to go. cheaper than race fuel. burns cleaner. doesnt ruin your sensors. And makes a lot more power! Def the way to go! Thanks for the comparison!

 

great gains at low boost wish i had some E around these parts for now its meth/91

 

Great thread.

Here is another chart of the two tunes. Same boost (20psi) with only fuel and timing changes.

 

Thanks, a lot easier to see the differences now. great gains for almost stock boost. Also looks like you spooled up a lil quicker too. Well done! Any chance of the 25psi chart?

 

The 26psi chart is here https://www.evolutionm.net/forums/ev...6hp-368tq.html

Those numbers are uncorrected at 2500' elevation. The corrected numbers were 396hp/388ft (me and Jim arent the biggest fans of corrected numbers, so we always post uncorrected and list the elevation.)

 

Also tuned a suby the other week that was first tuned for 91+meth, then we tuned it for e85. With only 1 more psi of boost and fueling changes, it gained 30hp/30tq over the 91+meth tune.

 

Im not a fan of corrected numbers either. I dont like to play the numbers game at all. I just like to look at the gains, power under the curve, reliability and the et down at then end of the track. That tune looks great, i especailly like how it holds power all the way out top till the end of the pull. Especially for the altitude too. Great Work! Nothing less than what i would expect from you. Never met you but ive Heard and read great things about you! subscribed!

 

dang Jay you make me want to go get a 55g drum and hand pump for my garage haha maby one day ther will be a station close good work