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Discussion Starter · #1 ·
Vehicle: 09 G8 GT-44k
Pacesetter LT, cat less, SLP pulley, K&N intake, 3200 Yank with cooler, ported tb, COMP cam 281/291- .644-.613, dod delete, milled heads. Tuned and made 430 rwhp/385tq.

17inch ZR1 camaro wheels (315) nittos. Unknown how old the tires are they felt hard, but had life left. Lowered the pressure. I'm chalking the bad times up to traction but wanted others opinions.

60ft- 1.928
1/8- 8.188 MPH 87.22
1000ft- 10.593
1/4- 12.633 @ 110.81

I foot braked it to 2000rpm, and just let it eat, and the times don't change. I heated the sh*t outa the tires and no difference. My posi made a gut wrenching noise so I called it a day after 4 passes. All around the same time. I was hoping for 11s but was sadly mistaken. What you guys think..also is my MPH low? Thinking I need new rubber and then go back...

Thanks
 

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Discussion Starter · #3 ·
Did it spin? Did it feel like it was shifting good? Im at a loss, thats terrible times for the mods...

How competent is the tuner? does he know anything outside of the dyno?? Something just aint right....Fluid good in the tranny? and yes the mph is way down...
Shifts find and I feel a little spin. One time it felt like the car shifted into 2nd right from the get go...is that in the tune? First time I used this tuner...
What MPH should I be seeing?
 

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I would think you should be seeing at least 115 mph and maybe more in the quarter. 430 hp isn't a bad number for those mods but not great. Which parts of the rpm range does it feel stronger in?
 

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Shifts find and I feel a little spin. One time it felt like the car shifted into 2nd right from the get go...is that in the tune? First time I used this tuner...
What MPH should I be seeing?
I'm no expert, but with your mods I'd expect to trap at least 115
 

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Discussion Starter · #8 ·
Well it ran a better 1/4 ET with the cam swap, plus if the cam hurt the car it would reflect the dyno numbers... so I'm starting to think its in the tune.
 

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plus if the cam hurt the car it would reflect the dyno numbers... so I'm starting to think its in the tune.
it most likely is the tune but just because good peak power was made doesn't necessarily mean that its not struggling to get there through the rest of the power band. Maybe the dyno graph would show?

what part of the country are you in? possibly if your are at 5000+ feet above sea level, that could explain a lot. Built NA motors struggle at high altitude...
 

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Discussion Starter · #10 ·
graphs Consistent. I'm in St. Louis, MO. It's getting re tuned on Sunday, by my old tuner who knows G8s.
 

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What is the cam duration at .050? and what was the density altitude that day? air quality is a huge factor
 

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Should be @230/240 cam. MPH should be much better as should the ET. Check the transmission fluid. If it feels like it is shifting right after you launch it, it is probably loosing pressure and dropping out of gear, then going back in gear.
 

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Discussion Starter · #13 ·
Should be @230/240 cam. MPH should be much better as should the ET. Check the transmission fluid. If it feels like it is shifting right after you launch it, it is probably loosing pressure and dropping out of gear, then going back in gear.
Fluids good...I checked after the install 2mnths ago. I hope in isnt the stall...I daily the car and don't notice it slipping.
 

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I agree with others above. With your HP, you should be trapping about 114-115 and seeing ETs of at least 12.25. Your 60 ft time is hurting you quite a bit. You should be able to get that down into the 1.7x range with decent track prep, and a good launch. A better 60 ft will make a big difference in that ET.
 

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I trapped 111mph with my baby Livernois cam on street tires stock convertor.
You have an easy. 11sec car. Something is Definately wrong
 

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Nitrous will fix the problem. jk....
 

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These look to be higher altitude #s. That cam at sea level would be upper 400s.
 

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Subd
 

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Discussion Starter · #19 ·
Had it re tuned yesterday and it feels like a new car, buying mickeys today's. hopefully problem solved :)
 

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Good to hear
 
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