waiting on meth??? why not just make the switch to E85 since you have TONS of injector headroom. Holy cow man. Well, Actually After I look back at it. I'm not sure your primaries will be up to the task. Approaching the limit before 4krpm :/

 

Lol

Lets see it

 

Yeah, I went back and forth on this. The major downside for me with E85 is availability. Only one station carries it locally, unfortunately I agree on the primaries, was thinking ID725's. But with meth I can fill up anywhere around here and no changing of injectors. Because it's a cold region here the -25*F • washer fluid is available all year, which has an MSDS reported methanol content of around 37%, IIRC.

 

Look, we got firecran's attention

 

Succeed or fail I will post my results!

 

Always creepin...

 

Pssh 12's. Be a real man and drop it to 10's.

 

I would but I don't want to hurt cran's feelings

 

Yeah so hurt.

 

You are always so serious, it's just banter man

 

Yeah so serious

 

So during a run I heard a strange noise, wondering if anyone has any ideas as to what it might have been. Sounds like a buzzing (not the GoPro rattling noise). Check between 0:49 and 0:51 seconds in this video:

 

Hmmm, hard time hearing anything on my iPhone ear pods, but was it almost like a creaking sound? Exhaust rattle kind of sound....?

 

Yeah, it is hard to hear. I actually can hear it better with my laptop speakers than earbuds, but likely because I know what I am listening for. It does sound like creaking, like an old metal chair. It was pretty noticeable in the cabin. I never found the cause, but curious if anyone might here it and say "yeah, that's x"... Meh...

 

hmmm, well I did have a similiar sound but I was only getting it at idle at random times when my rpm would dip for a second or so causing the engine to sputter and shake a bit. It was just my midpipe rattling off of a brace near where the midpipe and catback flanges meet under the car.... not saying that's what yours is but from what I can hear it was similar sounding. Mine was noticeable in the cabin but when I could really hear it was with the windows down and the car sitting in the driveway causing it to echo off the house.

 

Appreciate the feedback RM, I'll see if it comes back next season...

 

E85... Ok yomom, you got me back to evaluating this

One thing I am not sure about, and I'm not confident in my search results: does our ECU look at Lambda or actual gasoline AFR? I'm thinking Lambda, but the actuality would impact tuning strategy.... Ultimately I'm willing to throw some in the tank to figure it out.

 

Our ecu does not have a way to know the lambda of fuel in the car. I can't say if it uses lambda or afr, but either way it's based on 14.7 equals a lambda of 1.

If you get a ecu that can incorporate a flex fuel sensor then you can have both. And possibly swap back and forth with fuel. I don't know how much control the ecu will have. It would be nice if you could adjust boost based on fuel type.

9k is working on an adaptronic flex fuel solution right now I beleive.

 

Ok cool. I may pump in a tank just for research sake...

 

If you do that look at what the differance in volume between e85 verses gas. Then I'd start by scaling all injectors smaller by that much. Which will basically make them spray that percent more fuel and your fuel maps would stay kind of accurate.

Off the top of my head it would be 22 percent or so.

Also remember e85 should have a different target afr. More like 8:1 I think.

 

Appreciate the advice. I was under the impression that E85 requires more like 33% more fuel to achieve stoich, but haven't got all the answers yet. I feel fairly comfortable with getting started with E85, but my biggest question at this point is whether our ECU assumes the fuel is gasoline and factors this into the fueling tables, or if it just looks at stoich (lambda=1). Either way gives us some options to deal with it. I either need to keep reading or pour some in my tank and take sensor readings

 

Yeah I don't know the percent. Go for it. I would think even a bit lean would be safe with e85.

I am positive the car has no way to check the lambda of the fuel, but you can confirm it.

 

Maybe I have this all wrong, but isn't the only thing an oxygen sensor reads is how much oxygen remains post-combustion in the exhaust, aka lambda? So a particular ECU would need to be calibrated for gasoline for lambda 1 to = 14.7, no? Just trying to learn here

 

To do it right you need a ECU that can handle it and a flex fuel sensor. E85 is rarely E85. So unless you are mixing your own fuel you need a flex fuel sensor. I will be running the Adaptronic with a flex fuel sensor on my new PTP setup. Oh, and the you need the right injectors.

 

Good point about E85, I've read a bit about the mix being inconsistent. I'm not looking for a daily use of E85, just something for the drag strip. But that is where consistency will matter, of course

I am not set on E85 by any means. It has its benefits, but also challenges. Just exploring at this point and trying to learn. For the drag strip my initial plan was W/M injection, which is still the direction I am leaning. However, there is also unleaded 100 octane race fuel available by the gallon locally as well, but $14/gal.

Regarding injectors, I thought Injector Dynamics were E85 compatible?

How's the PTP coming along? Got any pics to post yet? I'm looking forward to seeing it!