Tuning the Z06, LONG, sorry about that
01-14-2019, 12:01 PM
#24
Race Director
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01-15-2019, 10:23 AM
#25
Burning Brakes
in short, the torque model needs to be adjusted properly.
second, if all your mods are listed, you don't have enough fuel capacity to run E85 and your injector pulse width is probably way too high, the ECM is backing up spark lead to allow a longer injection window without spraying through spark. ask your tuner what your IPW is on the pull(s).
get port injection (or god forbid meth injection as a band aid) and find the real potential for your combo.
second, if all your mods are listed, you don't have enough fuel capacity to run E85 and your injector pulse width is probably way too high, the ECM is backing up spark lead to allow a longer injection window without spraying through spark. ask your tuner what your IPW is on the pull(s).
get port injection (or god forbid meth injection as a band aid) and find the real potential for your combo.
01-15-2019, 11:25 AM
#26
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Higgs in your opinion is there any safe install of meth? I have a dedicated rear mounted meth tank (1.5 gallon) and am using a Alky Control system (pump, controllers, braided lines). I used the meth and a aux low pressure pump to be able to run 50% E-85 for drag racing.
01-19-2019, 04:54 PM
#27
Safety Car
Thread Starter
I'm just asking a question that took a really long time to get answered, don't get your panties in a bunch. Now that you have answered it, 6.3 ms, we can proceed....not a big deal at all. (btw, did you measure it based on logging IDC or did you log the pid for IPW?)
Yes, you should be fine there, but you are on the cusp of being limited. Keep in mind also that direct injection isn't only about total injection time. Exhaust valve comes into play, not just intake valve. Where the mixture is in the cylinder in relation to spark and piston location also matters now. It's less time than you think.
However. being only 20 hp up on a sea level car and at 6.3ms instead of 5 or less does raise other questions about the tune that I guess I won't ask since youre a little hard to talk to.....I mean, you asked the question....presumably asking in need of help? The ECM will retard spark and advance injection timing to keep you from spraying through it and start of injection timing and pulse width can tell us a lot about what is happening.
Yes, you should be fine there, but you are on the cusp of being limited. Keep in mind also that direct injection isn't only about total injection time. Exhaust valve comes into play, not just intake valve. Where the mixture is in the cylinder in relation to spark and piston location also matters now. It's less time than you think.
However. being only 20 hp up on a sea level car and at 6.3ms instead of 5 or less does raise other questions about the tune that I guess I won't ask since youre a little hard to talk to.....I mean, you asked the question....presumably asking in need of help? The ECM will retard spark and advance injection timing to keep you from spraying through it and start of injection timing and pulse width can tell us a lot about what is happening.
BTW: I got some advice to fix the timing pull, no thanks to you and it has nothing to do with what you say the problem is. Have a nice day.
01-19-2019, 08:16 PM
#28
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I asked a question about timing being pulled. You come on and in an insulting manner tell me that my setup and mods can't possibly handle E-85 and am out of gas. Now that's without my data and YOU. WERE. WRONG. Gee, that sure makes me want to march out as quickly as I can to provide you with more data to answer a question I never asked. Now you're slamming my tune without ever seeing it. Now that REALLY makes me want to take your advice. NOT!
BTW: I got some advice to fix the timing pull, no thanks to you and it has nothing to do with what you say the problem is. Have a nice day.
BTW: I got some advice to fix the timing pull, no thanks to you and it has nothing to do with what you say the problem is. Have a nice day.
01-20-2019, 08:52 AM
#29
Drifting
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St. Jude Donor '08
I asked a question about timing being pulled. You come on and in an insulting manner tell me that my setup and mods can't possibly handle E-85 and am out of gas. Now that's without my data and YOU. WERE. WRONG. Gee, that sure makes me want to march out as quickly as I can to provide you with more data to answer a question I never asked. Now you're slamming my tune without ever seeing it. Now that REALLY makes me want to take your advice. NOT!
BTW: I got some advice to fix the timing pull, no thanks to you and it has nothing to do with what you say the problem is. Have a nice day.
BTW: I got some advice to fix the timing pull, no thanks to you and it has nothing to do with what you say the problem is. Have a nice day.
01-20-2019, 11:48 AM
#30
Safety Car
Thread Starter
01-21-2019, 10:42 AM
#31
Burning Brakes
From what I've read, if you use the accepted norm of 310 degrees of fuel input, that's over 40% of time for pulse width, not one third, compared to port injection. At 6,500 that gives right at 8 milliseconds of acceptable IPW, and 6.3 is what I measured. I don't see the problem.
08-20-2022, 10:24 AM
#35
Pro
We tuned my 2015 Z06 and ran into a problem. Previously with a Halltech CAI, Mamo TB, Innovators West 9% lower pulley, and Norcal cat delete pipes on factory tune it ran well, but way rich it made 673 SAE RWHP and 720 SAE RWTQ. That's on a dynojet dyno. I then added a fuel sensor for flex fuel.
Before someone else says it. I know, I know, I broke all my own rules on this one.
1. I used a different dyno. (no choice here, it's the tuner's dyno). It's not even the same TYPE dyno, it's a dynocom dyno, and extremely "frugal" on it's HP values. It reads AT LEAST 3% lower than a dyno jet.
2. On ALL the runs (musta' been 20+ runs) I was spinning the tires on the dyno.
3. I didn't get a "before" run to compare to.
4. The conditions aren't the same as my other dyno runs so I really can't compare. It was 26 freeking degrees!!!
However, I believe the dyno results were acceptable for tuning, not comparison to earlier runs. 91 octane is the best E10 available here, tuned it, got some gains. How much? Don't know, we tuned, checked results, tuned some more, were satisfied that there were on more gains to be had. We then added 15 gallons of winter E 85 (really E 72 on my gauge) and tuned for it. Got more gains, BUT got a problem. At 6600 RPM it pulled 6 degrees of timing, causing a drop in power. Yes, we reset the redline to 6,800 RPM. We went through all the tables in HPtuners and can't see why. There is no KR there, it appears to be torque management, but why, and what do we do about it?
My final numbers were 684 SAE RWHP and 736 SAE RWTQ. I believe, on the dyno I always use, it'll be AT LEAST 705 SAE RWHP and 758 SAE RWTQ on a proven Dynojet. The issue that we need help with is the timing being pulled at 6,600 RPM.
Any ideas?
Before someone else says it. I know, I know, I broke all my own rules on this one.
1. I used a different dyno. (no choice here, it's the tuner's dyno). It's not even the same TYPE dyno, it's a dynocom dyno, and extremely "frugal" on it's HP values. It reads AT LEAST 3% lower than a dyno jet.
2. On ALL the runs (musta' been 20+ runs) I was spinning the tires on the dyno.
3. I didn't get a "before" run to compare to.
4. The conditions aren't the same as my other dyno runs so I really can't compare. It was 26 freeking degrees!!!
However, I believe the dyno results were acceptable for tuning, not comparison to earlier runs. 91 octane is the best E10 available here, tuned it, got some gains. How much? Don't know, we tuned, checked results, tuned some more, were satisfied that there were on more gains to be had. We then added 15 gallons of winter E 85 (really E 72 on my gauge) and tuned for it. Got more gains, BUT got a problem. At 6600 RPM it pulled 6 degrees of timing, causing a drop in power. Yes, we reset the redline to 6,800 RPM. We went through all the tables in HPtuners and can't see why. There is no KR there, it appears to be torque management, but why, and what do we do about it?
My final numbers were 684 SAE RWHP and 736 SAE RWTQ. I believe, on the dyno I always use, it'll be AT LEAST 705 SAE RWHP and 758 SAE RWTQ on a proven Dynojet. The issue that we need help with is the timing being pulled at 6,600 RPM.
Any ideas?
Hopefully, this problem has been solved by now, but if it were me I'd make my shifts before 6500 RPMs where the power loss issue is not occuring. Sounds like below that RPM the tune is stable.
The problem seemed to start with "...and then I added a fuel sensor for flex fuel...."
I see experienced folks recomending flex as the "First" mod one makes to their LT4. THEN add other things.
For a safe street tune I plan to go E85 + Tune first, then add headers (with stock exhaust), BMS filter, and HP tune for ~720bph. Thats about as good as gets if you want first gear to still be fun...and I do. Also, about as far as you can go before fuel delivery becomes an issue on full E85. Even here we need Nitto 555R or Toyo R888Rs to use 1st gear.
However, E85 is problematic for adequate fuel pressures, so generally can’t use above E40 without problems.
Cheers.
Last edited by 2FAST4U; 08-20-2022 at 03:41 PM.