Camaro Flex fuel conversion Qs

[mJolnir]

Just installed a dedicated motorsports flex fuel kit, really easy to install works great as intended, the car is a 2010 camaro SS auto, it has a vararam intake, headers, no cats, 3" exhaust, tsp vvt stage 1 cam, circle D 3400rpm stall, today after i tuned it with E40 (40% ethanol) it put down 437whp and 421 wtq, since i couldnt find this info on any thread i will post it here so anybody searching for this info before doing the conversion (like i was searching) finds it, at this power level stock pump and injectors cant handle E85 the E40 mixture is the most it can safely handle according to my opinion at this moment(on straight fuel inj duty cycle was at 63%, on full E85 it went to 115% and fuel pressure droped to 37psi, on e40 is at 89% duty cycle).

Now, on to my questions:

1- Other threads on flex conversion use the data from a 6.0 australian car, i couldnt find it in the repository, so i used a 5.3 tahoe for the evap factor blend and the impact factor blend, left the other tables as they where since they where populated already, but i dont know if this can get better by using other info, or if the 5.3 values that are very different would work OK?

2- The car is stalling on decel, it was ok on straight fuel but couldnt drive it on the streets as it was since it would stall each time i let go of the accelerator, used the flex fuel timing table from the tahoe and it made it drivable, but it will still stall and then bounce back into its normal idle rpm, how can i fix this?

3- my fuel pressure is droping to 51 psi (its doing the same on gasoline and E40) will i be ok or is it on the limit of what the fuel pump can flow?

4- Im getting burst knock when i put the hammer down, tried decreasing the mult vs rpm where i was getting burst knock, but that didnt work, how can i get rid of that?

5- the car seems to stay in Open loop all the time, since it has no cats i deleted the codes for the rear O2s and the cat, but im still getting them on the scanner, how can i fix the open loop part, and is it normal to still get the codes from the scanner?

here is my tune and a couple of logs:
camaro 2010 E85-3f.hpt
flexdyno4F.hpl
flexdyno3F.hpl

[10_SS]

5- the car seems to stay in Open loop all the time, since it has no cats i deleted the codes for the rear O2s and the cat, but im still getting them on the scanner, how can i fix the open loop part, and is it normal to still get the codes from the scanner?

Accorging to your O2's, they are swinging so your in closed loop. What makes you think your stuck in open loop? Not 100% sure about the codes part but if they are "permanent" then nothing you can do to hide them. If not permanent, then you can disable them in the DTC section of the editor.

Regarding the Burst KNock... the transition to WOT looks good but I see where your 1000rpms steady and you have weird burst knock kicking in.. my burst knock is fine, and I notice huge differences in your tables under Burst Knock:

My Base Vs CylAirDelta,
0 0 0 2 4 8 10 12 12
0 0 0 2 4 8 10 12 12
0 0 3 7 8 9 10 12 14

Your BasevsCylAirDelta:
0 0 0 0 0 4 4 4 4
0 0 0 0 0 2 4 4 4
0 0 1 2 3 6 8 10 10


My Mult vs RPM (especialyl in the lower RPMs).
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 rpm
0.00 0.125 0.125 0.125 0.25 0.5 0.5 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00

your Mult vs RPM (especialyl in the lower RPMs).
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 rpm
0 0.400 0.75 1.00 1.00 1.00 1.00 0.50 0.50 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

[mJolnir]

Accorging to your O2's, they are swinging so your in closed loop. What makes you think your stuck in open loop? Not 100% sure about the codes part but if they are "permanent" then nothing you can do to hide them. If not permanent, then you can disable them in the DTC section of the editor.

Regarding the Burst KNock... the transition to WOT looks good but I see where your 1000rpms steady and you have weird burst knock kicking in.. my burst knock is fine, and I notice huge differences in your tables under Burst Knock:

My Base Vs CylAirDelta,
0 0 0 2 4 8 10 12 12
0 0 0 2 4 8 10 12 12
0 0 3 7 8 9 10 12 14

Your BasevsCylAirDelta:
0 0 0 0 0 4 4 4 4
0 0 0 0 0 2 4 4 4
0 0 1 2 3 6 8 10 10


My Mult vs RPM (especialyl in the lower RPMs).
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 rpm
0.00 0.125 0.125 0.125 0.25 0.5 0.5 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00 1.00

your Mult vs RPM (especialyl in the lower RPMs).
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000 5500 6000 6500 7000 7500 8000 rpm
0 0.400 0.75 1.00 1.00 1.00 1.00 0.50 0.50 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

well if you check "fuel system #1 status" it stays in "OL-accel/decel" all the time.

the errors show even after i set the codes to "no error reported".

My burst knock tables are stock, same as the sample file for 2010 camaro that came with the HP tuners and a 2011 also auto that i scanned, they are all the same. I can try your setting to see if it solves my problem, but would love to learn how do they work so i dont go modifying them blindly.

[10_SS]

yes I did modify my Burst Tables to make them more sensitive at higher RPM's since I have a Whipple, and less sensitive at lower RPM. That's how you adjust them.

If your in pure SD/VE mode then Burst Knock will be messed up, but if your in MAF mode then it should be working fine.

[schpenxel]

That log is in closed loop, I don't know why the PID is reporting that it isn't. O2's are oscillating, STFT's are oscillating, etc.

To get rid of burst knock zero out the spark-->retard, "base vs cylairdelta" table in the burst knock retard section and that should do it. You can also zero out the multipliers in that same area if you want, any of them should do it.

For #2 try increasing min airflow. I don't know why but I had to mess with this on mine when I went to E85. Doesn't make sense, but it worked for me for some reason..

51psi isn't horrible and if it's the same as with pump gas then I wouldn't worry about it, but if it starts dropping any lower than that then I'd be worried. Keep an eye on it after long drives. Mine was fine if I drove for under an hour but after driving an hour or so it'd start dropping @ WOT. I guess the pump was getting hot or something.