Question about power curve with ethanol enabled.

[charleswrivers]

So I'll post the dyno off the webpage for an Si:

Ok! Now... given that the ethanol enable adds timing in the upper 1/2 of the RPM range at a value of +5 (at 4000 RPM, if memory serves), what is the method by which more power is added at lower RPMs... where the ethanol enable seems to do nothing with regard to timing?

Just curious. Thanks.

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[dc2turbo]

I didn't add any additional timing below 4000 rpm to limit the tq on the rods. I don't care for peak numbers

 

[360glitch]

Does the dyno chart reference the ethanol base map, or a custom E35 flexfuel tune?

 

[charleswrivers]

I didn't add any additional timing below 4000 rpm to limit the tq on the rods. I don't care for peak numbers

I'm in the same boat. I changed the 23# basemap and reduced boost under 4000 RPM, and that was also to keep rolling with my stock clutch.

I was just curious as to the power difference. If the only variable between the two curves is ethanol enabled vs not... I don't see where the extra power under 4000 RPM is coming from. That, or these are dynos of two different cars with a different set of mods. I'd think...

Car 1- Running 93... 23# basemap
Vs
Car 1- flexfuel added, still on the 23# basemap but with the ethanol map enabled, adding +5 to the ignition table at all points at and above 4000 would only show power improvements at that range.

...or was the example of a car 2 w/other mods thrown in?

 

[charleswrivers]

Does the dyno chart reference the ethanol base map, or a custom E35 flexfuel tune?

It just shows the, '23psi flexfuel E35'

 

[charleswrivers]

I was thinking of biting the bullet on a flexfuel setup. I was looking at the curves again but went, 'good God! Where's all that extra torque under 4000 coming from?!' There's got to be more here than ignition advance over 4000 RPM.

 

[360glitch]

I was thinking of biting the bullet on a flexfuel setup. I was looking at the curves again but went, 'good God! Where's all that extra torque under 4000 coming from?!' There's got to be more here than ignition advance over 4000 RPM.

If you are looking for max torque you can certainly add more boost and timing under 4000 with ethanol. The Ktuner and Hondata base maps are a great starting point for Flex Fuel, but they are fairly conservative compared to what you can get out of a custom tune.

Edit: The dyno chart referenced above demonstrates a tune that is still conservative on low end torque.

 

[charleswrivers]

If you are looking for max torque you can certainly add more boost and timing under 4000 with ethanol. The Ktuner and Hondata base maps are a great starting point for Flex Fuel, but they are fairly conservative compared to what you can get out of a custom tune.

Yep. Got that... big power under 4000 RPM is what I didn't want.

My question was simply...

If these are the same car, both on 23# basemaps... with one on 93 and the other running E35 w/flexfuel installed... where is all the extra power under 4000 RPM coming from? I saw no other things the ethanol enable does. I didn't know if all the cool guys running ethanol could comment as to whether or not running a basemap alone with the ethanol enable checked if it actually made more power under where the ethanol map added it's timing advance.

If the car does have more power under 4000 RPM... it's not coming from the ethanol map. It doesn't add ignition down there (unless I'm reading something wrong). It must be from something else ethanol is causing with the car. If so... what?

 

[KTuner]

It doesn't add ignition down there (unless I'm reading something wrong). It must be from something else ethanol is causing with the car. If so... what?

From what you're saying in the post it seems as though you may not have looked at the Ethanol Ignition Adjustment table. It says you have an Si and what you're saying you remember seeing doesn't match what's actually there for the Si.

 

[charleswrivers]

From what you're saying in the post it seems as though you may not have looked at the Ethanol Ignition Adjustment table. It says you have an Si and what you're saying you remember seeing doesn't match what's actually there for the Si.

I'll take another look. The only thing I had remembered seeing was the table with 0s across the board... then the section where it was 5s... I though they were all at 4000 RPM and up. This is from memory though, and I'll admit to having some 35 year old dementia.

I'm just doing a little homework to see what I'd need to do to let flex fuel survive on a stock clutch if possible. It looks like the bost table on the 23# basemap will have to get knocked waaaay down if the torque is improved that much in the low/midrange.

Thanks for the reply.

 

[KTuner]

I'll take another look. The only thing I had remembered seeing was the table with 0s across the board... then the section where it was 5s... I though they were all at 4000 RPM and up. This is from memory though, and I'll admit to having some 35 year old dementia.

I'm just doing a little homework to see what I'd need to do to let flex fuel survive on a stock clutch if possible. It looks like the bost table on the 23# basemap will have to get knocked waaaay down if the torque is improved that much in the low/midrange.

Thanks for the reply.

It ramps in before 4K. You can adjust that to fit your needs, of course. Boost as well.

 

[charleswrivers]

Alright... amendment:

The ramp up starts at 2750 at 1 and ramps to a peak of 5 at 5500.

It still doesn't seem to explain a 50 ft-lb gain for the ~500 RPM spot in the very beginning of the map... between 2200 and 2750.

I had looked at the adjustment table awhile ago, when I was using it as the basis behind adjusting my ignition table... I just had totally remembered it wrong, because I was gunning to add ignition while on 93, past the torque peak, based on all the reading I'd done beyond the Civic... which is also where y'all have it reach max.

Again... not sure how there's a ~ 50 ft-lb advantage between 2200 and 2750 on the E35 car, given there no extra ignition at that point. In it for the education, as to whether or not, ethanol provides any other improvements. I know it provides a cooler burn, since you have more of a lower BTU fuel getting injected... but I don't know if this effects power at all. I do stand corrected and apologize for putting out bad initial question based on info based on what I remember instead of looking to reverify what the table had. The question still stands, however.

 

[KTuner]

Gains should be seen everywhere when running ethanol. You're missing the bigger picture and are focusing on one additive table instead.

 

[charleswrivers]

Gains should be seen everywhere when running ethanol. You're missing the bigger picture and are focusing on one additive table instead.

Fair enough. I thought the method by which the power is added is by advancing ignition timing beyond which lower octane fuel allowed because it would knock... so that the pressure reached the piston closer to *just* after TDC and not later.

I didn't know there was something outside of the one table that affects how ignition is advanced based on ethanol being added. I know that table works in conjunction with another that has the ethanol % to determine how much of the ethanol ignition table number gets used and applied to the base ignition table... or whatever it's called (don't have Ktuner program open in front of me right now).

Just trying to learn. It seemed that there more going on beyond the ethanol ignition table alone since there was a substantial amount more power below where that table would seem to do anything and was trying to figure out the method by which more power was being generated. I'm in it for the knowledge. Thanks.

 

[KTuner]

I didn't know there was something outside of the one table that affects how ignition is advanced based on ethanol being added.

You do, in fact. Knock Control. We talk about it all the time.

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