42's and a 2.8.....
09-13-2010, 12:48 PM
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42's and a 2.8.....
So a good friend of mine has a tune for 42's and a 2.8 from hp tuners. I am currently 42's with stock pulley, Injen CAI, ZZP S2 H/E. He has tuned my car with hp tuners using the stage 2 tune from GM which is the same for S1 and S2. So basically I am stage 1.
Question is this.
My redline has been bumped to 7200. I am concerned with running a 2.8 pulley on the
42's. I have been told it will work and several people run them. Will I run into problems assuming I run 2 heat range colder plugs, and only rev to 7000? This should be fine. Please confirm!
Thanks.
Question is this.
My redline has been bumped to 7200. I am concerned with running a 2.8 pulley on the
42's. I have been told it will work and several people run them. Will I run into problems assuming I run 2 heat range colder plugs, and only rev to 7000? This should be fine. Please confirm!
Thanks.
09-13-2010, 05:22 PM
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If the tuner can tune. Then you can run 42's on a 2.8. If you do not trust him enough, then get 60's
False
False
Last edited by WickedSS2005; 09-13-2010 at 05:22 PM. Reason: Automerged Doublepost
09-13-2010, 05:25 PM
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You'll make HP atleast up to 6.8/7k on the m62/stock head. Look at a dyno graph. TVS is dif, makes power up to 8k (limit of our PCM, well, 8,192rpm is the ACTUAL limit)
09-13-2010, 05:40 PM
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Were you tuned? And the IDC is a calculated value, not a true value. Were you going lean up top? Pulse Widths?
7.2k, or so it's said. I have hit above that numerous times tuning my personal car. No issues
7.2k, or so it's said. I have hit above that numerous times tuning my personal car. No issues
Last edited by WickedSS2005; 09-13-2010 at 05:41 PM. Reason: Automerged Doublepost
09-13-2010, 05:43 PM
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looks like ill start shifting there sometimes then. i would have already went tvs is E85 wasnt 20 miles from me. The powergains on pump fuel just aren't worth it to me so ill prolly go turbo next year.
09-13-2010, 05:46 PM
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another benefit of reving higher is not only making power but also when you shift it drop you off in a better part of your powerband, mines set at 7400 I rarely rev that high though unless I'm in a close race, otherwise its a nice shift at 7k.
09-13-2010, 05:47 PM
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Just because your power fell off, doesnt mean everyone else's will. But thanks for sharing.
09-13-2010, 05:49 PM
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No, it didn't get lean up top but I really only took that setup up to 6700 or so and my log showed 104%. It still pulled fine. That was just before I switched to 80's and e85. I'm not entirely sure if that setup was tuned either, it ran stupid rich and came on the PCM I got with the motor I picked up and put in my car.
09-13-2010, 05:51 PM
#24
my last dyno on the cobalt before i sold it, i made power all the way to 7500rpm and it never dropped. i had the tvs but it never dropped, ran out of rpms