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I have one primary question. Read everything below if you like, but I primarily want an answer to the following question:
Those of you with TVSes running 93 octane, at what IAT2 does your tune start pulling timing?
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I'm trying to determine how the timing is set up on my recently-upgraded-and-remote-tuned TVS-equipped Cobra. I/C and H/E system is all stock, running 70/30 water/coolant, with Water Wetter. It's running a 2.8" upper pulley (boost peaks at 19 PSI, then drops to 18 PSI close to redline), and I'm using 93 octane plus a pint of Klotz octane booster in each tank.
Here are some test results using an OBD2 scan tool:
2nd gear, 3250 RPM, 117F IAT2, 16.5 degrees (pedalled it to WOT due to traction issues, start of pull)
2nd gear, 6000 RPM, 120F IAT2, 16.5 degrees
3rd gear, 6000 RPM, 129F IAT2, 15.0 degrees
4th gear, 6000 RPM, 142F IAT2, 14.0 degrees
(IAT1 was around 75, and ambient was in the mid 60s.)
Seems pretty obvious that the tune is pulling timing as the IAT2 readings increase.
I've read that the factory tune starts pulling timing as low as 100F, and that it's based on some sort of setting of timing retard at 150F. So, the tune specifies at what IAT2 reading timing should start being pulled, and then specifies how much timing should be pulled at 150F IAT2, and the computer interpolates between 0 timing being pulled at 100F IAT2, on up to xx timing being pulled at 150F IAT2. So, hypothetically, if it pulls 10 degrees at 150F, it would pull half that timing at half that temp difference, so 5 degrees being pulled at 125F. Someone please correct me if I'm wrong.
I don't know if 16.5 degrees is the "no timing pulled" setting (like, maybe it doesn't start pulling timing until beyond 120F), or if it's already been pulling timing as low as 100F. I'll try to do a pull tomorrow morning, when the intercooler coolant is (hopefully) still below 100F, and see what the timing is. However, since it's obviously pulled 1.5 degrees of timing between 120F and 129F, it's definitely started pulling timing somewhere between those temps.
Also from my reading, tuners generally raise the floor at which the ECM starts pulling timing, but I haven't found any consensus.
So, at what IAT2 reading should the ECM start pulling timing?
How much timing should be pulled at 150F IAT2?
Here's a link to the video: http://www.thefleshrocket.com/images/cars/cobra/videos/IAT2_monitoring_pull.m4v
Here it is on Youtube, but it's only at 360P quality--not sure why:
I have one primary question. Read everything below if you like, but I primarily want an answer to the following question:
Those of you with TVSes running 93 octane, at what IAT2 does your tune start pulling timing?
------------------------------------
I'm trying to determine how the timing is set up on my recently-upgraded-and-remote-tuned TVS-equipped Cobra. I/C and H/E system is all stock, running 70/30 water/coolant, with Water Wetter. It's running a 2.8" upper pulley (boost peaks at 19 PSI, then drops to 18 PSI close to redline), and I'm using 93 octane plus a pint of Klotz octane booster in each tank.
Here are some test results using an OBD2 scan tool:
2nd gear, 3250 RPM, 117F IAT2, 16.5 degrees (pedalled it to WOT due to traction issues, start of pull)
2nd gear, 6000 RPM, 120F IAT2, 16.5 degrees
3rd gear, 6000 RPM, 129F IAT2, 15.0 degrees
4th gear, 6000 RPM, 142F IAT2, 14.0 degrees
(IAT1 was around 75, and ambient was in the mid 60s.)
Seems pretty obvious that the tune is pulling timing as the IAT2 readings increase.
I've read that the factory tune starts pulling timing as low as 100F, and that it's based on some sort of setting of timing retard at 150F. So, the tune specifies at what IAT2 reading timing should start being pulled, and then specifies how much timing should be pulled at 150F IAT2, and the computer interpolates between 0 timing being pulled at 100F IAT2, on up to xx timing being pulled at 150F IAT2. So, hypothetically, if it pulls 10 degrees at 150F, it would pull half that timing at half that temp difference, so 5 degrees being pulled at 125F. Someone please correct me if I'm wrong.
I don't know if 16.5 degrees is the "no timing pulled" setting (like, maybe it doesn't start pulling timing until beyond 120F), or if it's already been pulling timing as low as 100F. I'll try to do a pull tomorrow morning, when the intercooler coolant is (hopefully) still below 100F, and see what the timing is. However, since it's obviously pulled 1.5 degrees of timing between 120F and 129F, it's definitely started pulling timing somewhere between those temps.
Also from my reading, tuners generally raise the floor at which the ECM starts pulling timing, but I haven't found any consensus.
So, at what IAT2 reading should the ECM start pulling timing?
How much timing should be pulled at 150F IAT2?
Here's a link to the video: http://www.thefleshrocket.com/images/cars/cobra/videos/IAT2_monitoring_pull.m4v
Here it is on Youtube, but it's only at 360P quality--not sure why:
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