Transitional Know and E85?

[turbocamino1]

Been fighting with some transitional knock most of the summer. At 26Lbs.boost didnt have it.. but now tuning for 28-30Lbs i cant get rid of 1.6 KR on s/master... i can hear it for JUST a split second when i wack it in first or second. I have sped up the alky..,turned up the alky and added fuel as well. I dont hear it on a roll-on pull in 3rd and my w/band always shows 10.8-11.2 during WOT. Adding the fuels mentioned does what its sappose to as i can see the W/band changes. So i have been thinking and reading that maybe the stock ECM just cant keep up. The new 6265 i have spools really fast...once it comes on boost it goes to max in a split second. My ECM is not very old but maybe the old technology is just that..old. I have been getting my list of parts to switch to e85. I read that this fuel makes for an even faster spool.....will this make for a worse transitional KR. or will the e-85 be an aid,(octane /cooling)..or is an aftermarket ECM the ONLY answer....or is 1.6KR not a worry at all. TIA.

 

[jasjamz]

Does your fuel pressure rise as fast as your boost. Is it 1:1? Are you getting wheel spin? I read a post where a guy had a regulator leaking air pressure. Lower your alky turn on point. Does that help? Try pulling 2* of timing. See if it goes away? E85 may fix it.

 

[turbocamino1]

Transitional KNOCK and E85...(Sorry,too much holiday cheer) No data log available,but my in car f/press. gauge looks to follow boost though. Yes,there is always wheel spin now. Alky starts to spray at 12lbs. now...havent tried any lower.... and timing in first is down to 19*. It seems that with the 9/1 pistons the car is more timing sensitive now...21* rattled bad.

 

[jasjamz]

Is your chip for 93/91 and alky or E85 and alky? What is it burned for?

 

[turbocamino1]

Eric's chip,93/alky ...19*,26Lbs Haven't pulled the trigger yet for e-85. I've not sped the alky pump ramp all the way yet...it's a little past 2 o'clock and pump pressure/gain is at 7 and i added (i think) 5% fuel fueling for the added boost... WOT 0/2's went down to 10.5 when fuels where added. It may not have needed both fuels bumped,but i wanted to test and see if the transitional went away or changed at all but transitional stayed the same @1.6KR.

 

[jasjamz]

So right now you are using E85 and alky? If so that is the problem. You have to have a E85 chip. Alky and E85 on a 93/Alky chip will not work.

 

[KevinB]

Ditch the alky and go e85 if there is a local source.
Get a wideband to monitor your at ratio.
Try to be 11.0:1 gas scale.
Run about 20 degrees timing with 30 psi
Do not run a projected tip plug, try to find a medium cold plug. Gap at .025 or so.

You will have a good running car. Lots safer than alcohol injection imo.

 

[jasjamz]

E85 is cool, alky is too. With his injectors and combo, he won't make more than 18-20 psi on straight E85. With that being the case, his car will need the alky to extend that to 22 or 24psi if he is lucky. The TT chip needs more fuel across the whole map to run E85. It will cost him injectors, lines, chip reburn and a better pump setup to really be E85 ready. If not, he will be just as susceptible to engine damage as any other car that runs too lean or detonates. Good point on the plugs too. I see Gabby's teaching has been help both of us...Wink!

 

[KevinB]

I see it as sell the current injectors and alky kit to pay for a double pumper and injectors. Stock lines will be enough for mid tens.