slow times at track, overtimed?

[8aHemi]

E85 / 8psi / L76 / tr6060 / 20 degrees timing / .81 lambda target.

Hey guys I finally got around to going to the track in my G8, I only participated in the roll racing section as I dont have a tire yet. Anyway the best trap speed I could achieve was 124mph from a 40 roll.. That seems pretty low to me considering this car made 550whp on 93, and is now on e85. Looking at other cars with similar setups, they seem to run 130+ in the 1/4 mile.

Whats odd to me is im getting slight KR towards the top of 4th gear, with 20 degrees, which 20 to me sounds pretty low for ethanol, but what do I know.

with the gearing it has currently, im shifting into 4th right at the 1/8th mile, and running it out to the end. This was also on a 90 degree day, probably didnt help anything.
In the file, the stoich is all jacked up because I found that my flex fuel sensor ethanol content drops at WOT, so i just made it all the same number to avoid issues there. Im pretty sure I need to move the sensor to the feed rather than return.

e85 track3.hpt124mph trap.hpl

Thing feels great until you hit 4th, it seems to struggle to pull that 1:1

[Lakegoat]

At WOT, Lambda is pretty steady at .77 to .81L. If it's going lean at WOT, you need to log Injector duty% and Injector bank 1 and bank 2 ms. How is your fuel pressure? Under MAP sensor offset, that should be -11.25. Put the Stoich back to where it should be---looks like you are double stoich for your injectors? Fuel calcs will be off with throwing a 19 in there. Looks like you tuned around it.
There is not much knock, take 1 degree out where it starts and see if that's it. OR go to knock sensors and make initial level 150 and min level 50. See if that works before removing timing.

[Alvin]

I'd pull some timing and see if the KR goes away.. First step.

[edcmat-l1]

I'd pull some timing and see if the KR goes away.. First step.

Yep and see if it slows down or picks up.

[STAGEUP]

I see a TR6060, are you sure you're "driving" it? (AKA Driver mod)

[8aHemi]

At WOT, Lambda is pretty steady at .77 to .81L. If it's going lean at WOT, you need to log Injector duty% and Injector bank 1 and bank 2 ms. How is your fuel pressure? Under MAP sensor offset, that should be -11.25. Put the Stoich back to where it should be---looks like you are double stoich for your injectors? Fuel calcs will be off with throwing a 19 in there. Looks like you tuned around it.
There is not much knock, take 1 degree out where it starts and see if that's it. OR go to knock sensors and make initial level 150 and min level 50. See if that works before removing timing.

Its not going lean, It was around 15% rich first pass with the tweaked stoich ratios. I dont have a way of monitoring fuel pressure during a pass, I really should invest in a gauge, but its set at ~60psi with 2x 340lph pumps. The issue is ethanol content dropping during acceleration, which ive heard is caused by "vapor from the regulator" but idk.

Good catch on the MAP offset, should i change the barometric offsets as well to a zr1? I believe its a zr1 map sensor, PN 12592525

Worth mentioning, this isnt the tune file i drive the car on, I just noticed ethanol content dropping off first pass and decided it would probably be a good idea to temporarily make stoich all the same value, in case it caused issues especially since the learning delay is set to 0 for flex

[8aHemi]

I see a TR6060, are you sure you're "driving" it? (AKA Driver mod)

Yeah my first 2 passes i was "driving it" and then my clutch let go in 4th, unfortionatly those 2 passes I was in the process of tuning so it was pig rich, and only went a 118mph and on the second pass the clutch was slipping. Whats odd is i let it cool down and made 2 more passes and it was fine, ended up at 124mph best, but I wasnt shifting nearly as aggressivly as i could, i just wanted to be able to drive the car home at that point. Shifts definantly werent slow by any means though.

[8aHemi]

I'd pull some timing and see if the KR goes away.. First step.

Yeah I was thinking of trying 16 degrees and see what that does for me, is there any way to measure acceleration using HPT? I wont be back at the track for another month or two most likely, I guess worse case I can borrow a buddies dragy.

[yevgenievich]

Hpt tracks time and shows speedometer. If speedo is accurate, would be close enough for testing

[hjtrbo]

([8001.113.avg(-200)]) - ([8001.113.avg(200)])

[Alvin]

Yeah I was thinking of trying 16 degrees and see what that does for me, is there any way to measure acceleration using HPT? I wont be back at the track for another month or two most likely, I guess worse case I can borrow a buddies dragy.

This is where a dyno comes in handy. Weather day to day, track conditions, etc.. Often on most setups there is a wide window of timing that makes about the same power. You won't know until you try it on the dyno.

[JayRolla]

I highly recommend getting it on a dyno. My local dyno lets me flash between runs as long as the tunes are already set and its only $100 for three hits. My LSA engine was pretty aggressive with the stock tune, granted they are lower compression. At 6.5psi the stock timing map hits 22-23.5* and if IAT are low it would advance 4-6*. I could see 28-30* and would get 2-4* timing retard on 91 octane sometimes.

With e85 and my pulley upgrade I see 10-12psi. On pump gas I am at 18* with zero detonation. On e85 at the dyno I ran hits of 20*,22* and 24*. From 20 to 22 I made almost 20whp. From 22 to 24 I made 5whp. So, I stopped. I backed it down to 22* to keep everything happy. I never have gotten any knock at WOT on my setup even at 26* on e85.

Like you said I would drop it to 16-18* to start and see if that knock goes away 1st thing. I use a draggy on the street when making changes. I always use the same road and try to do it when DA matches the last run. Works pretty good.

[STAGEUP]

I finally got to see this tune. Needs work, thats for sure. Take a look at bank 1. Something funky going on with one of the cylinders on bank 1. Take a laser thermometer to the primaries and see if all cylinders are within 20 degrees of each other on bank 1. Looks like you may have a weak injector, or fuel pressure is dropping. Wont know until you log IDC.

Also, you have flex fuel enabled, but your stoich table says otherwise. Because of the way your fueling is set up, your cylinder airmass is also extremely low. Also need to fix this right away.