[KILLA BEE]

So I got a retune today, I was on E37 prior and bumped it up to E47 with CAI, Lt header same mods ONLY. ITS in the 50s I’m thinking I’d be okay #s however I drove an hour and a half to get there with a little happy foot here and there then I had to add more E with more happy feet to get the gauge to display proper E%. Finally got to the shop and went basically to doing pulls. So at 6 psi of heat soak boost left l ended up with 628 wheel. I was 637 on E37!!
Same shop during the Warmer months and a different shop location. (Not far but still) the dyno far as I know want SAE so don’t ask lol. The dyno Shown is the one prior to 628 the last pull. Looking at the forum it’s right on point. I suppose a re dyno on 8 or 9 psi would yield around 649. However, even with the heat soak I can still a significant jump from the timing adjustment l/fuel

[LGAFF]

What gear was it dynod in?

[KILLA BEE]

Originally Posted by LGAFF

What gear was it dynod in?

Not sure but I just asked him

[MatthewAMEL]

Why tune for a specific Ethanol percentage? Are you not using the FlexFuel sensor?

[KILLA BEE]

Originally Posted by MatthewAMEL

Why tune for a specific Ethanol percentage? Are you not using the FlexFuel sensor?

You have to use a sensor to use Ethanol gas. And you have to tune to a certain percentage so you won’t run lean or mainly destroy your high or low side fuel pump, I have a gauge Inside the car which tells me the percentage. So E50 is kind of like safe zone DEPENDING on how many mods you have. The more mods generally means the less ethanol you can use

[KILLA BEE]

Originally Posted by LGAFF

What gear was it dynod in?

7th

[arpad_m]

Originally Posted by MatthewAMEL

Why tune for a specific Ethanol percentage? Are you not using the FlexFuel sensor?

From what he wrote, I think he implied tuning to and always using a specific maximum percentage of ethanol as the most beneficial blend that his fuel system allows.

The stock LT4 fuel system doesn't allow the use of E85, it simply can't pump that much fuel that quickly, but diminishing returns kick in past E60-E65 anyway. If he only ever puts E50 or lower in, technically the tune doesn't need to be spot on past that point (thus "tuned to E50"), although I would ask my tuner not to do that and scale the tables properly through to E85 anyway.

[Megahurtz]

I was sorta confused at what OP is trying to say. The grammar was difficult to interpret. I thought he was trying to say E37 vs E50 gains are shown on the graph but I could be wrong.

[KILLA BEE]

Originally Posted by arpad_m

From what he wrote, I think he implied tuning to and always using a specific maximum percentage of ethanol as the most beneficial blend that his fuel system allows.

The stock LT4 fuel system doesn't allow the use of E85, it simply can't pump that much fuel that quickly, but diminishing returns kick in past E60-E65 anyway. If he only ever puts E50 or lower in, technically the tune doesn't need to be spot on past that point (thus "tuned to E50"), although I would ask my tuner not to do that and scale the tables properly through to E85 anyway.

He was looking to see how much E I could go with until he started to see the low or high side fuel pumps start to struggle.