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Mastermind46

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I include dyno data in the ThInK Auto Tech filter thread for the lids on and off. There was a clear difference with the lids off and hood open. I also had a very large fan blowing into the engine bay so maybe that added to it. Hood down were consistently the lowest numbers. Granted, we are talking max change of any run being a couple of horsepower, but the trends were consistent.

The hp numbers could be different due to correction factor based on the day he did dyno pulls with the tune. He mentioned 3k ft DA. The baseline may have been from a cooler day or time and had a lower CF.

I think the power (other than torque on E85) is not going to be significant. All of the other changes you can make seem to be where the value is.
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Garcia172

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So the question is... (and I have not researched this... new to S650), is there a flex fuel kit that integrates with the ecu?
 

ZXMustang

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So the question is... (and I have not researched this... new to S650), is there a flex fuel kit that integrates with the ecu?
no.

And I posted my results of e85 on a stock car weeks ago lol.
 

Garcia172

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no.

And I posted my results of e85 on a stock car weeks ago lol.
When you posted your results isn't the issue. The issue is, driving on a single tune... E85 only, is a problem when you have a 16 gallon fuel tank, and given E85 has about 25% less energy, you're range goes down by 25% (so we're talking about being hard to take on a trip when you need to be glued to E85 pumps).

This is why I asked about the true flex fuel kit (like I have on my EvoX... which lets you run pump if you have to or any blend in between).

I don't know anything about the S650 ECU (I'm used to running Motec ECU's)... which is why I asked the question in the first place.

Personally.... if you don't have a true flex fuel setup, and it's not a race car (which we would never use pump E85 anyway), and it's not a turbo car.... what's the point?
 

ZXMustang

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When you posted your results isn't the issue. The issue is, driving on a single tune... E85 only, is a problem when you have a 16 gallon fuel tank, and given E85 has about 25% less energy, you're range goes down by 25% (so we're talking about being hard to take on a trip when you need to be glued to E85 pumps).

This is why I asked about the true flex fuel kit (like I have on my EvoX... which lets you run pump if you have to or any blend in between).

I don't know anything about the S650 ECU (I'm used to running Motec ECU's)... which is why I asked the question in the first place.

Personally.... if you don't have a true flex fuel setup, and it's not a race car (which we would never use pump E85 anyway), and it's not a turbo car.... what's the point?
The point is having quite a bit more power on tap for any situation you might want it for. LOL is this a serious question? You also realize you can swap back to 93 once you run the e85 down to E. Then just fill up on 93, and after a few miles flash your 93 tune. You realize that right?
 


Garcia172

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The point is having quite a bit more power on tap for any situation you might want it for. LOL is this a serious question? You also realize you can swap back to 93 once you run the e85 down to E. Then just fill up on 93, and after a few miles flash your 93 tune. You realize that right?
Not sure what's so funny. I'm just pointing out the "not so obvious" to the daily driver guy.

The problem is that no street car runs down to empty. So it's always going to be blend. Been there done that. It's not good for a daily driver unless you're surrounded by yellow E85 pumps... lol

Switching maps (dual maps) is a total bandaid setup which never works good.

You mentioned a flex fuel tune you're working on. Check out the Innovate stuff.. but that again depends on the capabilities of the factory ECU (which I'm not familiar with). But a true flex fuel setup brings E85 to everyday drivers.

Which... is why I asked in the first place. (and that allows you to sell a lot more kits :-)
 

ZXMustang

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Not sure what's so funny. I'm just pointing out the "not so obvious" to the daily driver guy.

The problem is that no street car runs down to empty. So it's always going to be blend. Been there done that. It's not good for a daily driver unless you're surrounded by yellow E85 pumps... lol

You mentioned a flex fuel tune. Check out the Innovate stuff.. but that again depends on the capabilities of the factory ECU (which I'm not familiar with). But a true flex fuel setup brings E85 to everyday drivers. Which... is why I asked in the first place.
If you want to run PCMtec then we can do a real flex tune with sensor - once they support gen4. But on gen3 they do. Everyone else doesnt do them anymore. They are very finicky and rarely work as intended and no you and everyone else isnt watching datalogs to make sure the inferred blend is correctly learned before it finishes its learning cycle.

And yes you can run the car down to basically E and fill up on 93 and then the next tank full you will be pure e10 93. The previous tank, you might be e12 or e15 but you are well within the car's fuel trim ability to correct for up to 35% +or- fueling. You are completely over thinking this with nothing more than hear-say and "been there done that" experience. I personally tune these professionally and Im telling you its perfectly reasonable for anyone at any level to run e85 until you need gas. Then fill up on 93, drive 10 miles than flash back to your 93 octane tune and have the car easily correct for any fuel discrepancy of which there will be very little. Hell guys running around on e40 like me on the stock tune only seeing the car correct for 10-15% fuel deficit.

You dont need a flex fuel system especially since you see no value in running e85 anyway on any street purpose car thats not some racecar. So why even need it? Running a straight 93 tune 24/7 street duty, then running it down to E before you refill to E85, drive it a bit then flash to your E85 tune for a night of racing that hard?
 

Garcia172

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The biggest problem, and the reason we don't run pump E85 in our races cars, is the quantity of ethanol in pump E85 is never the same (in fact it can easily vary by 15-25% which is huge). So without knowing the quantity of actual ethanol in the gasoline, your tune must be compromise and somewhat conservative on the timing maps. The problem again is how conservative?

That's one main issue.

I've run dual maps in my Evo X (500RWHP at all 4) and I can say from direct experience it sucked. A total bandaid compared to the full flex fuel setup.

Anyway... I'm not trying to get in a keyboard jockey war. I was really interested as to whether or not a true flex fuel setup existed. Which is something that would be great for a street car (I'd buy the setup).
 

ZXMustang

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The biggest problem, and the reason we don't run pump E85 in our races cars, is the quantity of ethanol in pump E85 is never the same (in fact it can easily vary by 15-25% which is huge). So without knowing the quantity of actual ethanol in the gasoline, your tune must be compromise and somewhat conservative on the timing maps. The problem again is how conservative?

That's one main issue.

I've run dual maps in my Evo X (500RWHP at all 4) and I can say from direct experience it sucked. A total bandaid compared to the full flex fuel setup.

Anyway... I'm not trying to get in a keyboard jockey war. I was really interested as to whether or not a true flex fuel setup existed. Which is something that would be great for a street car (I'd buy the setup).
FYI you dont need pure e85 to get the complete knock protection you get from higher E content. You are not going to see any knock no matter what from anything E60+. You might get false knock from something like headers, but not actual spark knock. Anything e70+ is safe with most e85 tunes you would get from any tuner. The reason people want pump E without blending is because blending is hard and people are lazy. E50-60 is the sweet spot on ethanol based fuels for knock protection and maximum timing. But blending to E60 vs just pumping in straight pump e85 is a pain. But you wont see any difference between e60-e85.
 

Garcia172

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FYI you dont need pure e85 to get the complete knock protection you get from higher E content. You are not going to see any knock no matter what from anything E60+. You might get false knock from something like headers, but not actual spark knock. Anything e70+ is safe with most e85 tunes you would get from any tuner. The reason people want pump E without blending is because blending is hard and people are lazy. E50-60 is the sweet spot on ethanol based fuels for knock protection and maximum timing. But blending to E60 vs just pumping in straight pump e85 is a pain. But you wont see any difference between e60-e85.

The sweet spot is fuel that will let you run all the ignition timing you need without detonation. I haven't played with these cars tuning wise (nor am I going to) but if that engine can run all the ignition timing it needs with 50-60% ethanol great (not too surprising considering it's a NA engine).

But for a daily driver (at least for me), I would be interested in a true flex fuel setup.

BTW E85 makes almost 85RWHP (at all 4) difference on the EvoX at 32-33lbs. Impressive for something coming out of a public pump.
 

Garcia172

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Also... as another data point: Dynoed the LS7 race car on race fuel 110 leaded, then E85 pump (which was about 78%-79% ethanol. Only made 5RWHP difference at 650RWHP. Not worth it (even if the pump E85 was consistent)
 
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Also... as another data point: Dynoed the LS7 race car on race fuel 110 leaded, then E85 pump (which was about 78%-79% ethanol. Only made 5RWHP difference at 650RWHP. Not worth it (even if the pump E85 was consistent)
Not worth it? Have you compared the cost of 110 to E85 per gallon?

It is also kind of tough to fill up on 110 in a street car.
 

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What is this? Is header false knock common? What can be done about it?
Better block bolts. If it’s rocking that much the ghost cam became reality.
 

Garcia172

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Not worth it? Have you compared the cost of 110 to E85 per gallon?

It is also kind of tough to fill up on 110 in a street car.
These are race cars not street cars. I was only pointing out the power difference between the 2 fuel types.

Nobody runs pump e85 in expensive race engines because the amt of ethenol varies too much.... Hence the 110 leaded race fuel (at the race track).
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