2009 ZR1 Timing Issue

This zr1 is not cooperating and the car will hit commanded timing at WOT briefly, but will start pulling mid way through dyno pulls. IAT and ECT tables are not pulling at all. There is no knock and no burst knock on the log. Traction control via spark has been disabled.. What else is there that I could be missing?

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Originally Posted by gkviper192

This zr1 is not cooperating and the car will hit commanded timing at WOT briefly, but will start pulling mid way through dyno pulls. IAT and ECT tables are not pulling at all. There is no knock and no burst knock on the log. Traction control via spark has been disabled.. What else is there that I could be missing?

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post a scan and tune file. If I had to guess I would say its because of MAT

Attachment 46064Attachment 46065

Here is a log and the tune attached.

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Originally Posted by gkviper192

Attachment 46064Attachment 46065

Here is a log and the tune attached.

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looks like MAT or IAT 2 temp to me, pulling about 3.5* by 6400 rpm.

I must be missing something. I see it hitting commanded, and then going up from there, not pulling. Could it have something to do with the AFR spark correction ?

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Originally Posted by realcanuk

I must be missing something. I see it hitting commanded, and then going up from there, not pulling. Could it have something to do with the AFR spark correction ?

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So what are you expecting the total timing to be? 17*? Take a look at your af correction and variable cam table

I must have missed something myself, if you take a look at your original post it would seem you are asking in regards to timing being pulled, not added

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Originally Posted by GPGTP

So what are you expecting the total timing to be? 17*? Take a look at your af correction and variable cam table

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Its not my thread.... was just making an observation..

Attachment 46068

I apologize. attached the wrong tune for that Log. Attaching here.... :doh:

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Originally Posted by gkviper192

Attachment 46068

I apologize. attached the wrong tune for that Log. Attaching here.... :doh:

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That makes more sense now. Look at the g/cyl and the timing table. Seems to make sense. Under 1.69 you have 21 degrees which is what you are getting.

I never looked at a ZR1 tune before. Plenty of timing it seems.

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Originally Posted by realcanuk

Its not my thread.... was just making an observation..

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lol my bad.

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Originally Posted by realcanuk

That makes more sense now. Look at the g/cyl and the timing table. Seems to make sense. Under 1.69 you have 21 degrees which is what you are getting.

I never looked at a ZR1 tune before. Plenty of timing it seems.

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I agree, I don't see what the issue is here. Set the 1.69 row higher if you don't want timing to fall off

BTW, they run about 25 degrees stock

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Originally Posted by GPGTP

I agree, I don't see what the issue is here. Set the 1.69 row higher if you don't want timing to fall off

BTW, they run about 25 degrees stock

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No worries.. lol

That's pretty amazing. Didn't think they would take that much with boost. Interesting.

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Originally Posted by realcanuk

No worries.. lol

That's pretty amazing. Didn't think they would take that much with boost. Interesting.

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Yea surprised the hell out of me the first time. Also, from my experience, there isn't much to gain from tuning the CTS-V's and ZR1's stock and bolt on. Haven't done one with smaller pulleys yet so I can't comment on that.

dont you think your targeting a little bit of a lean mixture? 12.3?