Thread: Yes You Can... Tune & Run on E85.

Hello gents, I know there have been a few pepz interested in tuning on E85/gasoline mixtures, and even a few who are tuning straight E85 as well. However due to the lack of availability of E85 on the coasts there has not been too many results posted. The primary beifit of going to E85 is that it burns super cool when compared to 91 octane pump gas but it burns the equivilant of 104 octane when used in the correct amounts. In addition, since it runs so cool you can throw quite a bit of timing at it with no risk of detonation. Average HP gains from doing nothing more than the mods nessisary in order to convert to E85 are 50-60HP.

In addition a month or so ago I asked if anyone had heard of/used a MAP ECU. There were comments on both sides as to the ability and comparibility of these units to others such as the calum ecu.

This post is meant to shed some light on the benifits of running E85 and to demonstrate the ability of the MAP ECU. So with that said, here we go...

1st well start with the mods to my engine:

BB DET
3" exhaust
Hotshot IC setup
Greddy type RS
JGY ex manifold
GT 2871R
JGY top feed fuel rail
MSD 72lb injectors
Nismo FPR
Walbro 255lph fuel pump
Greddy Profec B Spec
MSD Digital SCI+ & Blaster 2 coil
OEM DE ECU Using MAP ECU piggy back Air/Fuel controller
MAP ECU ELIMINATED my MAF so I'm on straight air speed density. (No need for Z32 or cobra MAF mod to my ECU)

Elevation: 5280ft
Fuel: E85 Ethanol
Boost: 17PSI
Fuel PSI: 45 @ idle

When tuning with E85, the best rule to follow is that it burns 30% leaner than regular pump gas so you must run 30% more of it. Hence the 72lb inj's. Using the MAP ECU we were able to lengthen/shorten the injector pulse in order to even out the A/F ratios and here are the results. Remember, this motor is internally stock and is at 5280ft.



After a closer look at my A/F ratios we noticed that there was a slight dip where the mix was leaning out a little. The reason for this is because I was hitting the maximum injector pulse width for the 72lb'ers. If I go with some 1000cc top feeders we will be able to bump the boost to 20-23 PSI and bump HP to around 380 at the wheels.

Well there it is. If anyone cares to comment feel free. Also if anyone has any questions or needs more info please ask. Here is the info on the MAP ECU:
www.mapecu.com


Also, if you live anywhere near the Denver area and need parts or any type of fab work or tuning done to your ride, then these are the people to go and see! They have mad experience in a wide range of tuning software and have tuned everything from honda civics to lamborghinis. beyond that, the fab work and customer service are TOP NOTCH! If your passing through or need more detailed info on the MAP ECU, give them a call.
www.MACautosport.com


Dave

That is awesome.
How does your fuel economy compare (E85 vs regular)?

Well this is definately NOT a fuel economicly motivated conversion, but it comes down to this. Your going to have to run 30% more fuel for this to work so your milage will decrease by at least 30%. (rough math here) But as long as the price of E85 stays at 30% cheaper than 91 or better, than your still making out or breaking even. (and you still get the extra ponies) 91 octane here runs about $4.19/gal and E85 goes for $2.70/gal, so I'm still doing pretty good. You sure need to fill up a lot though if you can't keep your foot out of it.

Been making 414 WHP on a daily driven, swapped S13 with Nismo 740cc injectors for a while now (GT3071R or GT3076R, can't remember) using E85. Four 1000cc injectors are good for 550+ WHP on E85. The extent of the inevitable corrosion to the factory rubber seals and to the steel lines and tank has yet to be determined.

Good to hear someone gave the MAP ECU a try. It sounded like a decent idea to me. =]

Thats awesome man, the guy who tuned my car has a simmilar setup but with the 1000's and he's doing 550. I'm thinking I may go cams and the 1000's to push mine to 430-440, but I dont know yet. That would require a new clutch. I was toying with the idea of seeing if I could hit 500 on stock internals, but if I hit it the B15 tranny might go then as well.

I'm pretty sure the GTi-R block can handle 500 WHP no problem completely stock with a good tune. I don't think the B15 tranny would have any trouble either.

My plan is E-85 on the NX for my tune. AEM EMS with 1000cc RC injectors. Any opinions on initial tune changes to go with? SHould I increase my whole fuel map 30% as a base then work it from there?

Brent

That's what we did Brent. Although if I recall we multiplied the entire map by 1.25 (25%). Should get you in the ballpark. Maybe work with the idle areas first and see what multiplier gives you the same A/F at idle, then apply that multiplier to the whole map. If I remember correctly WOT stuff was almost dead on after 25% increase in pulse width, it was partial throttle that took the most work (as always).

E85 may not get the best gas mileage but if it's E85 or race gas, E85 is considerably cheaper. Nice work.

When we tuned mine on the MAP ECU it did not have a map to start with, so he just made up a base map it would idle on and then went to the dyno and the wideband for the rest. Took maybe 8 pulls to get it down. The only problem I'm having with E85 is making sure I'm near a gas station that sells it when I'm running out on that tiny 10 gallon tank of mine. Lol