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Old 05-20-2007, 09:08 PM   #1
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Default Controlling Shift points

So I went to the track today, first time since I installed a ZZP PCM and 1.95 rockers. The car was shifting at around 5500 rpm through first, but went all the way up to nearly 6000 rpm in second. I'm not a programmer, so I'm not quite sure why this would happen - I would think the PCM would have been programmed to be consistent. Anyone have any thoughts?
The end result was that I was running about a tenth slower than before I changed the rockers and PCM.
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Old 05-20-2007, 09:17 PM   #2
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Not sure about the trans, but regarding the track times, has your car had time to "learn" the new mods?
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Old 05-20-2007, 09:34 PM   #3
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All your mods look like your getting air into the engine, how do you get the air out?
Time for headers or pem, high flow cat at least?
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Old 05-20-2007, 09:42 PM   #4
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You should talk to ZZP and ask about the shift points. Like Pdad said your doing a good job of getting the air in but you need to do more to get it out. A high flow cat might help some and can be had for pretty cheap.


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Old 05-20-2007, 11:45 PM   #5
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The car did have plenty of time to learn - a couple hundred miles at least, not including the 80 miles to the track.

Putting in headers might be a future project for me, but according to Intense'* website, you should be able run the package I have w/o headers - I'm similar to package #2 except I'm only running a 3.5 pulley. On top of that, the headers really come in handy in the higher rpm band when you are pumping air at a higher rate. The car feels flat mostly in the idle to 3500rpm range, then seems to pick up a bit. I'm still wondering if the PCM is the culprit. Other than doing scans, I don't have a program or the know how to know what else is going on with the PCM, but here are some more facts: I drove to the track from a cold area and about 20 or so miles crossed a front where it was 20 degrees warmer and more humid compared to where I drove from. Is it possible the PCM would not be able to have adjusted quickly enough for optimum performance? Another fact: driving home, during at least the first half of the trip, the car was burning much more fuel in cruise than on the way to the track. So again, did the PCM now readjust the heavy acceleration at the track and take 50 miles to adjust back to cruise mode? Doesn't seem like it should take that long - my stock PCM never behaved like that.
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Old 05-21-2007, 01:07 AM   #6
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I don't think a 20 degrees change would require a long time for the PCM to adjust. I know many times when I'm heading to work in the morning it might be 50 and when I coming home it'* 75 and my car feels fine.

I still think you should contact ZZP and ask them about the PCM. Also try to find someone in your area with a scanner whether it'* on this site of a Grand Prix forum.


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Old 05-22-2007, 12:39 PM   #7
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TT ZZP. They are suggesting I send back the PCM for an update - hopefully this does the trick.
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