E85Forum.com

4RingAR · Joined: 24 Sep 2010 Posts: 2

Car: 2001 Audi allroad quattro tiptronic, 2.7L V6 Twin Turbo, 125k miles, 350 estimated crank hp.

Current engine modifications: Cat-back exhaust, gutted downpipes, stage 1 "91octane" ecu upgrade, hybrid blow off valves.

Goal: Cheap and easy way to get some more power out of this car when I want it.

Options:
A) Buy an E85 flex-fuel kit and get a 100octane ecu program to use when Im on E85.

B) Get larger injectors, adjustable fuel pressure regulator, and the 100oct ecu program. Switch to the 91octane program and lower the fuel pressure when on regular gas.

Option A seems to be the easier option, but Im not sure how well these kits respond to modified vehicles.

Which path should I take?

Cheers!

Obormot · Joined: 27 Jun 2008 Posts: 44 Location: Ukraine

Hello!

adjustable fpr and bigger injectors are better solution than conversion kit, but it can not solve cold start problem and installation is more comlex. if installation is not a problem and temperatures in your region do not falls lower than +10...+15C, you can use it.

if you can tune ECU, you do not need any conversion kit - just write all AFR changes into ECU, or make wider LTFT and STFT range if you can. also you can change enrichment for cold starts and for WOT mode. but at WOT modes fuel flow thru stock injectors may be too low.

so maybe FPR or bigger injectors + ECU tuning will be better solution.

conversion kit is good if you do not want to do any complex procedures - just take it from the box, plug to connectors of the engine and drive away Smile

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European E85 conversion kit
http://bioadapter.com

4RingAR · Joined: 24 Sep 2010 Posts: 2

thanks for the quick reply.

unfortuantly temperatures do drop below 10*C often, in fact I have even seen -20*F(-30*C).

That said, my plans for E85 use would likely just be occasional in the warmer months and when I autocross the car, so I dont think the cold weather would be a huge, deciding factor.

I dont have the ability to tune the ECU myself, I have to use off-the-shelf programs, which is why I would use a 100oct program for E85. I figure that the advances in timing and boost pressure would allow me to extract more power from the E85 than a basic 91octane program would allow.

Obormot · Joined: 27 Jun 2008 Posts: 44 Location: Ukraine

Hello!

there is no troubles in "everyday" using E85 (or E70 - winter blend) fuel in winter if you have a solution for cold start problem - kit with this function or tuned ECU.

for very cold weather heating of fuel before injection will be helpful - you can make simple electic device or heat exchanger with engine coolant.

as i understood, turning spark timing does not giving big advantages, so maybe you donot need to tune ECU.

for turbocharged engines E85 are much better, than gasoline - becouse of great cooling properties and octane rating, you can gain boost presure without overheating mixture in cylinders and detonation.
_________________
European E85 conversion kit
http://bioadapter.com

skiracer · Posted: Tue Sep 28, 2010 4:18 pm Post subject:

The 100 octane map won't work on E85 since the AFR's will be drastically different.
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'06 Evo IX Stage 1 by RRE,Walbro 255lph fuel pump,RC Engineering1000cc Injectors, AVO exhaust,RRE flash, (325whp @ 22PSI 91 octane, 353whp @ 25psi on 100 octane, 383whp @30psi on E85),Zeitronix wideband/Ethanol Content Analyzer, Defi gauges