Finally switched to E85

Well after doing some research I decided to give E85 a shot and see how the TA likes it.
Tuning wise it was pretty easy. The biggest challenge was the initial transition from gas (E10) to E85 which was actually E70. Once I realized that and switched stoich to E70 it was fine. So it's time to buy a fuel composition tester to eliminate the guess work in the future because there are 3 Classes of E85.

Summer Blend: Class 1 (min 79% ethanol)
Spring/Fall Blend: Class 2 (min 74% ethanol)
Winter Blend: Class 3 (min 70% ethanol)

Even though it should have been Class 2 in the pump, it seems it was actually Class 3 based on my initial struggles. Of course, I can't confirm until I get a tester.

Some quick observations:
- Tuning in lambda is much easier with E85. It's been awhile since I actually tuned in lambda, but for E85 it's simply less confusing.
- No more putrid gas smell. Even though my car was actually pretty good about this, the E85 burns and smells much nicer compared to gas. After about 120 miles or so the tailpipes are actually cleaner.
- Gas mileage sucks as expected.
- Car seems to idle smoother. It also likes to idle right at lambda or slighter richer compared to slighter leaner (14.7-15.0) on gas.
- Throttle response is crisper, especially at tip in.
- It seems to like .80 or richer lambda for PE enrichment at WOT.
- I added a couple of degrees of timing at WOT at it didn't seem to respond as well as adjusting lambda.
- Car sounds slightly different at idle and at all driving conditions. I don't know why but it does.
- Injector duty cycle shot up to 88% at WOT, but the WB reading was almost exactly as commanded. I'm using Delphi 42 # right now, so it looks like it's time for new injectors.
- I now keep 3 tunes in my V2 at all times; Gas, E70 and E85. Even though there are quite a few E85 stations here in MN, I did this just in case.
- Make sure your Gas tune is dead on before tuning in E70 or E85.

All in all, I was pleasantly surprised how easy it was. Even though SOTP tells me the car runs better performance wise, I will wait to confirm it at the track.

Just a quick update.

- I bought a cheap tester I use each time I fill up with E85. I bought it online from Summit Racing.
- Even though the idle was good, I added 3 degrees of timing at idle which helped to smooth it out even more.
- I checked the plugs (TR6 gapped at .035) after 200 miles and noticed the mark on the ground strap was noticeably lower compared to running gas. So I switched to a plug that is two steps colder and now the mark is right on the bend as it should be. No fouling after extended idling or general driving. Because E85 burns cleaner it takes longer for the mark to show up on the plug, so I will check them again after I put some miles on them.
- Added 2 degrees of timing at WOT which was really hard to tell a difference. Overall, SOTP indicates a noticeable difference, but we'll see.
- I may increase the fuel pressure to help with injector duty cycle, but I will wait for now.

So far I still like it even though mpg is down, but I like how it burns and smells cleaner with a better throttle response.

Thats very impressive work!

What all was involved 'mechanically' to allow your vehicle to do E70-E85?

It is an interesting change you have done. It took me weeks just to figure out how to 'tune' E10. Like you said, keeping widebands and PCM all in Lambda or EQ was really the trick.

Again, good work.

Thanks. I didn't change anything mechanically including the fuel system. I run a Racetronix fuel pump with an Aeromotive FPR and 42-lb Delphi injectors. I have the fuel pressure set a little on the high side at 61 psi at the rail.