Tuning questions

[IheartSTI]

I am not attempting to tune my own car although I do I have a couple questions about tuning to further my understanding of what my car is doing. I was just reading about ignition timing and I know you can advance/retard timing for better tune on race fuel...but how much? Would it depend on octane and o2 content in the fuel? If it were a cold day at the track would this also become a timing factor? I was hoping I could receive some feedback to help me better understand. Thank you

[IheartSTI]

And when you start messing with ignition timing will the knock sensor still function properly to prevent any disasters?

[Dean]

Race fuel is not required. 91 octane can take a little more timing, especially at altitude.

The knock sensor does little good in open loop/higher RPM where most power is made, so it can't protect you when you need it. This is why logging and the right gauges are critical.

EGT, Wideband 02 and some form of determining HP/torque is how you determine how much timing to use.

There are a bunch of references in a thread I started a while back and haven't gotten back to.

http://www.seccs.org/forums/showthread.php?t=5829

[IheartSTI]

Originally Posted by Dean

Race fuel is not required. 91 octane can take a little more timing, especially at altitude.

The knock sensor does little good in open loop/higher RPM where most power is made, so it can't protect you when you need it. This is why logging and the right gauges are critical.

EGT, Wideband 02 and some form of determining HP/torque is how you determine how much timing to use.

There are a bunch of references in a thread I started a while back and haven't gotten back to.

http://www.seccs.org/forums/showthread.php?t=5829

after reading the information on that thread it explained a lot of things in great detail... thanks

[knucklesplitter]

Originally Posted by Dean

The knock sensor does little good in open loop/higher RPM where most power is made, so it can't protect you when you need it.

This is true, but the rpm threshold where the ECU stops looking at knock can be changed/increased (with Enginuity, Ecutek, etc.)

[Dean]

Originally Posted by knucklesplitter

This is true, but the rpm threshold where the ECU stops looking at knock can be changed/increased (with Enginuity, Ecutek, etc.)

Do you have any references where this has been effective? I was under the impression that at higher load/RPM, the knock sensor was not able to distinguish knock due to the higher background engine noise.

[sperry]

Originally Posted by Dean

Do you have any references where this has been effective? I was under the impression that at higher load/RPM, the knock sensor was not able to distinguish knock due to the higher background engine noise.

The knock sensor is just a microphone. I'm not sure how much control you have over it in the stock ECU, but in the Hydra you can set the rpm cut off as well as the threshold... in that way you can probably bump up the rpm and tweak the threshold to exclude the additional noise but still pick up the knock if it's loud enough.

[knucklesplitter]

UTEC looks at the stock knock sensor all the time and is known to have good detection - lots of settings. They even sell this feature seperately - known as "KnockLite": http://www.turboxs.com/more_info.php?ID=212

In the stock ECU I only know how to change the RPM cut-off, so I dunno how effective the stock ECU's setting are at higher rpm.

[Double Phister]

I have the knocklite. I like the way it is aware of the background noise floor as related to RPM.

[IheartSTI]

I was reading a ecutek thread and a couple people mentioned the knock sensor was nearly ineffective after 5000 rpms. I would think with all the vibrations and abstract noises at high rpm's it would would likely play a factor on how well the knock sensor works. what rmp is a car likely to knock? under high loads or rpms?

[sperry]

Originally Posted by IheartSTI

I was reading a ecutek thread and a couple people mentioned the knock sensor was nearly ineffective after 5000 rpms. I would think with all the vibrations and abstract noises at high rpm's it would would likely play a factor on how well the knock sensor works. what rmp is a car likely to knock? under high loads or rpms?

The knock sensor is quite literally turned off at like 5400 rpms on the stock ECU. The car cannot pull timing between there and red-line because the mic is off.

Knock can occur at any time, but more-so under high loads, which is also when it's more destructive.

[knucklesplitter]

Originally Posted by sperry

The knock sensor is quite literally turned off at like 5400 rpms on the stock ECU. The car cannot pull timing between there and red-line because the mic is off..

Yes, but this rpm is easily tuner adjustable.

UTEC and Knocklite (and Hydra I assume) still look for knock on the stock sensor well above 5400. My UTEC has sensed real knock on my car as high as 7000rpm and pulled timing, flashed the light at me, and logged it. It's one of the few things UTEC does really well. But it is still using the factory sensor.

[knucklesplitter]

Originally Posted by R4ND0M_AX3

I have the knocklite. I like the way it is aware of the background noise floor as related to RPM.

Is your knocklite using the factory sensor, and if so how is it connected - spliced or what?

[IheartSTI]

So today i was doing some logging and i ran into a problem... my car just went to high idle and would not let me throttle. I just got a tune from i-speed but I am not sure how accurate the tune was because it was emailed to me. (I have the EcuTec) here are some reading i got while logging maybe someone could tell me what my car is doing.

Minimum Maximum
Primary wastegate duty cycle: 83.1

Manifold absolute pressure: 2.0 27.1

Manifold relative pressure: -11.6 13.3

ignition timing: -8.5 45.0

knock correction: -13.0 5.5

Fuel Injection #1 Pulse width: 0.77 18.43

air/fuel sensor #1: 0.75 1.40

Advance Multiplier: 1.0 1.0

atmospheric pressure: 13.6 13.6

mass air flow: 1.99 238.16

air/fuel correction 1: -25.0 25.0

air/fuel correction 3: -51.6 -43.8

air/fuel leaning #1: -1.6 1.6

air/fuel sensor #1 current: -1.38 1.75

air/fuel sensor #1 resistence: 25.0 39.0

rear o2 sensor: .005 1.015

CPC valve duty ratio: 0.0 100.0

tumble valve position sensor right: .34 4.24

tumble valve position sensor left: .3 4.24

accelerator opening angle: .0 100.

throttle motor duty: -62 77.

fuel pump duty: 0.0 100.

roughness monitor cylinder #1: 0 0

roughness monitor cylinder #2: 0 0

roughness monitor cylinder #3: 0 1

roughness monitor cylinder #4: 0 1

so i am not sure what this all means and if it looks good or bad... feedback please

[IheartSTI]

the first numbers are minimums and the second are maximums

[sybir]

Email tuning scares the living shit out of me.
Even scarier is that I-speed isn't demanding logs so they can evaluate and send you a new map, no matter what. It should be an ongoing development and review process. I didn't think Bill was that lazy (he used to tune pretty lean, but was a conscientious guy), or are you just checking with us in addition to talking to him?

Just my 2 cents.

[IheartSTI]

well i am calling him back today and letting him know i am emailing my logs. Hopefully with more information he will be able to tune more accurately. But as of now my car wont boost more then 12 psi

[IheartSTI]

btw... the reason i did internet tuning is i am currently living in north idaho and need to be able to get my car back to reno in 2 weeks. hopefully i can get a better tune down there

[GST Mike]

I have not logged with that setup for a while but the fact that is shows at some point that you ran -8.5 degrees of timing and -13 degrees of knock correction would have me a little concerned.

Mike

[IheartSTI]

Originally Posted by GST Mike

I have not logged with that setup for a while but the fact that is shows at some point that you ran -8.5 degrees of timing and -13 degrees of knock correction would have me a little concerned.

Mike

I just emailed the guy at i-speed my logs and we will see what will come of the situation. So far they have been good to me.

[sperry]

Originally Posted by GST Mike

I have not logged with that setup for a while but the fact that is shows at some point that you ran -8.5 degrees of timing and -13 degrees of knock correction would have me a little concerned.

Mike

+1. That's the motor trying to protect itself. You probably don't want it making more than 12 psi of boost if it's already knocking. In fact you should probably just reflash it with a low-boost, low redline "safe" map and baby the car until you can get it back to civilization and on a dyno for a custom tune.

[IheartSTI]

Originally Posted by sperry

+1. That's the motor trying to protect itself. You probably don't want it making more than 12 psi of boost if it's already knocking. In fact you should probably just reflash it with a low-boost, low redline "safe" map and baby the car until you can get it back to civilization and on a dyno for a custom tune.

haha back to civilization... that was great.

[IheartSTI]

Originally Posted by sperry

+1. That's the motor trying to protect itself. You probably don't want it making more than 12 psi of boost if it's already knocking. In fact you should probably just reflash it with a low-boost, low redline "safe" map and baby the car until you can get it back to civilization and on a dyno for a custom tune.

i talked to the guy at i-speed and he said the +1 is fine... when it gets to 30+ then i have a problem.

[sperry]

Originally Posted by IheartSTI

i talked to the guy at i-speed and he said the +1 is fine... when it gets to 30+ then i have a problem.

Huh? "+1" means "I agree"... it's not a reference to the data.

[100_Percent_Juice]

Originally Posted by IheartSTI

i talked to the guy at i-speed and he said that my ROFL settings and my WTF meter is fine... when it gets to OMFG then i have a problem.