ethenal %

[fluxzl1]

anybody who has a flex fuel tune notice any differance in power with a lower ethenal % like 40 to 50% rather than 70 to 75%??

[beersngars]

I think so. The only time I run 93 is late in the fall when I want to dilute the E85 for storage and again in the spring when I get it back out and have E85 in the tank. I am getting 72%-75% E85 consistently in my area and can feel the difference as I ramp up and down the alcohol content. Of course this is on the butt dyno so YMMV.

[gsxrturbo]

I would like to know to,I see our e85 runs about 76 to 77 percent,but I cant tell powerwise as mine spins more then I like

[ABM Camaro]

Ive thought about this Mod, but Im not sure about it . Ive hear good and bad about changing the fuels.

[hammdo]

50% to 85% makes a few hp difference but it's not as much as you think. If you flex tune, PCM will compensate. Most places in our area are no lower than 65% when it's cold out. In fact, I dyno'd on 59%..

-Don

[Juiced1]

On a flex fuel tune you will be missing some timing for sure with only 40-45% ethanol. On a boosted car that would make a difference. We generally see gains from 70-80rwhp when we do a flex fuel tune running 85% ethanol. So if you're only around half that ethanol content you're probably cutting your gains in half of the total potential.

[fluxzl1]

Originally Posted by Juiced1

On a flex fuel tune you will be missing some timing for sure with only 40-45% ethanol. On a boosted car that would make a difference. We generally see gains from 70-80rwhp when we do a flex fuel tune running 85% ethanol. So if you're only around half that ethanol content you're probably cutting your gains in half of the total potential.

thats odd, ive seen several tuners that say there are no gains above 40%, is it in there tunes or maybe because the cars fuel system is not able to run
over 40%????

[hammdo]

First 4 minutes tells you once above 50%, diminishes returns... This is from the tuning school...



And another good one:



-Don

[Juiced1]

They are referring to a direct injection motor that didn't have the fuel system to take any more then E40. If they ran pure E85 on that car it would have lost fuel pressure and probably blown up. Adding more ethanol will add more power but obviously you need the fuel system to keep up.


With the LSA as long as you have the injector and the fuel pump there will be higher gains with better fuel.

[hammdo]

I have all of that and more in mine ;o). Tuned by GPI but we really didn’t see a huge gain above 60%. ID1050x, DSX Flex fuel kit/aux pump, DSX FPCM, ZL1 fuel pump, ported LSA blower, 2.45 upper, 18% lower — forged and stroked, etc.

Also note Fasterproms and I believe the tuning school said port injection would make less power vs direct too (since I’m port probably why not as much gain)...

Just wanted folks to know each setup is very different and some don’t gain as much — note the CTSV in Fasterproms as an example..

On e only upgrade, I gained 36 RWHP, 25 RWTQ and that was before going with the 416 forged setup — had all the fueling upgrades, ported blower with 2.45 pulley, still have the dyno pulls to show with no glory pulls..

Just wanted to show it really does depend —

I’ve added meth, RPM 5" CAI, and NW 102 since the 747 dyno on e70, May see a bit more now ;o). My duty cycles are 85-88% at WOT and .78 Lambda with meth and 95% duty cycle on e only so probably need ID1300Xs now ;o)...

Now, this is on ‘pump’ e - not the pure stuff — pure may make a difference..

-Don

[fluxzl1]

well in the last 2 weeks ive ran 50% and 70% ethenal and the 70% is quicker
on throttle and mid range from what i can tell... starts better on 50%...

[DrkPhx]

Originally Posted by fluxzl1

thats odd, ive seen several tuners that say there are no gains above 40%, is it in there tunes or maybe because the cars fuel system is not able to run
over 40%????

There is a point of diminishing returns, and depending on car and mods, it may vary. The real goal is to achieve MBT (maximum brake torque) with the optimal timing. This is achieved by testing on a dyno.

The big hp gains from E85 are from adding additional spark advance well above what the same motor on premium will safely accept. There are a few ethanol spark tables as well as multipliers that are used to arrive at the final spark advance based on the ethanol %. If set up correctly; the higher the %, the more spark. How much for each % depends on the tuner. There are other variables as well; the more aggressive the base tune on premium, the less gains on E85. If you normally run 91, you should see good gains with E85. I saw an honest 40-50rwhp gain from running E60, but I normally ran 93. Also consider there is very little (if any) pump E85 that is true E85. Depending on the time year and location it may go as low as E50%.