Pinging at WOT...

[iamdub]

I thought E85 had more HP (advanced timing?) but less MPG...that was the experience my brother had with his flex fuel Silverado and I had with a flex fuel F150...I recall them even being advertised with more horsepower when using E85...anyway, they seemed more peppy to me but lost 2-4 MPGs

Bill

They do have more power. I can never remember the specifics, but, in the GMT900s, it's something like +11HP and +13TQ. This is on actual E85. You'll lose about 27% fuel economy.

My local E85 pumps are actually around E65 consistently. So, about 23.5% lower ethanol than E85. As such, I "only" lose about 21% of my E0-E10 fuel economy. I can't say the extra power is anything I can feel so much. But, there's too much else goin on with mine that it's irrelevant when comparing stock on E0 to stock on E85.

 

[Mudsport96]

If it was flexfuel it would have a flexfuel tag on the rear of the Denali. My 05 Denali is not a Flexfuel. Both of my 03 Vin Z Tahoe LT's are Flexfuel.

Possibly. My L59 Tahoe has no markings whatsoever that it is flex fuel

 

[Fless]

Possibly. My L59 Tahoe has no markings whatsoever that it is flex fuel

An L59 IS a FF engine. The only marking on mine is a tiny sticker inside the fuel door -- you know, where non-FF vehicles say not to run E85, mine says it's okay. And the "Z" engine code (L59) is the other clue.

 

[rockola1971]

An L59 IS a FF engine. The only marking on mine is a tiny sticker inside the fuel door -- you know, where non-FF vehicles say not to run E85, mine says it's okay. And the "Z" engine code (L59) is the other clue.

What year is yours?

 

[Mudsport96]

An L59 IS a FF engine. The only marking on mine is a tiny sticker inside the fuel door -- you know, where non-FF vehicles say not to run E85, mine says it's okay. And the "Z" engine code (L59) is the other clue.

Yes, the Z is the only clue on mine. Hell the fuel cap isn't even yellow like most flex vehicles. So if the average Joe had it and didn't know how to decipher the VIN, he would never know.

 

[Fless]

Whast year is yours?

2004 with the physical alcohol sensor.

 

[Fless]

Yes, the Z is the only clue on mine. Hell the fuel cap isn't even yellow like most flex vehicles. So if the average Joe had it and didn't know how to decipher the VIN, he would never know.

Mine was the same, although I have no idea if the fuel cap was ever changed. But there is that little sticker on the inside of the fuel door that was pointed out to me.