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VHP heads

Old Jan 15, 2005 | 07:17 PM
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ok finally got these on the 99 formula. had to fix the tranny in the 00 formula back in december when i was originally going to put them on. here's pics of the install here: http://www.stealthram.com/1999pontiacformula.html then click VHP Head Install
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Old Jan 25, 2005 | 08:37 PM
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track times i have as of 1/19/04. after dynos not yet. i have my flow sheet finally. i'm reluctant to post the results after what happened in the AFR VINCI thread. one thing to note on my heads. these are my 4.8L heads i had them port. vinci only likes to use 5.7L heads. i will post up flow chart shortly.

track testing - i went to the track on 1/12/05 to get current times. best was 13.144 @ 105.63 and 13.144 @ 105.67. best run on 1/19/05 was 12.918 @ 107.55 with not tune. i've been driving around with a scanner looking at knock retard and o2s. i'm getting about 3.5* knock retard in the 4000 range and running a little lean by looking at the o2s.

i'm also dealing with a right bank low cat efficiency that started on the 1/12/05 track night. the car has bested a 11.84 @ 121.16 on 175 n2o. on 1/12/05 it went 12.04 @ 113.26 no nitrous runs were made on 1/19/05. went to do a run and the main power toggle switch broke. didn't know until i went to engage the nitrous during the run. but, with the knock retard of 3.5*, it may have been a good thing.

after dyno results when i can make some time to get it on the dyno. oh and as far as the dyno numbers go, i put the car on 2 dynos the same day for comparisons. i used macedo motorsports dynojet 224e that uses WINPEP7 at about 3:30pm (he has dynoed 1000hp vipers on it). then went straight to vinci's dynojet 248e that is DOS based and inground and made runs at about 4:30pm. the WINPEP7 showed 307 rwhp and 313 rwhp. vinci's showed 327 and 333 rwhp.
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Old Jan 25, 2005 | 08:38 PM
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ok here's the flow chart for my 4.8L head that vinci ported for me.

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Old Jan 25, 2005 | 08:39 PM
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now here's where i rebaselined the car on jan 13th vs april 04 just to see if there were any differences. runs were made when engine temps were at 185* according to scanner readings.
ACTUAL
SAE
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Old Jan 25, 2005 | 08:39 PM
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now these are the graphs from macedo motorsports. runs were made when engine temps were at 185* according to scanner readings.
ACTUAL
SAE
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Old Jan 25, 2005 | 08:40 PM
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now. test parameters are changing. because of the right cat coming apart, i will be hollowing the hi-flow cats out and adding o2 simms. will go back to track for more runs before tuning. at least we can see how much more i can gain by 'removing' cats.
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Old Jan 25, 2005 | 08:41 PM
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and the timeslips
NA before heads
175 N2O before heads
NA after heads no tuning
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Old Jan 25, 2005 | 08:41 PM
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cats are hollowed out and o2 simms in place. going to track tomorrow night for updated times.
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