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Going to dyno my GXP on Sat., advice?

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Old 11-17-2011, 07:12 PM
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Default Going to dyno my GXP on Sat., advice?

Hey all. I'm going to be running my stock 07 GXP on a Dynojet dyno this Saturday. Any suggestions, tips, pointers, things to watch out for, quirks about these cars I should know about? This place usually lets me run my own car so I figured I'd disable the TC and Stabilitrak, then just run it up to 3rd gear with the Tapshift and let her fly. Should I be worried about my factory 75k mile trans heating up too much? I've never run an Auto on a dyno before, only manuals so I'm an auto-dynoing virgin lol...
Old 11-17-2011, 07:33 PM
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Originally Posted by BlauGXP
Hey all. I'm going to be running my stock 07 GXP on a Dynojet dyno this Saturday. Any suggestions, tips, pointers, things to watch out for, quirks about these cars I should know about?
Yes.. don't expect big numbers


I'm going to guess 225hp at the wheels. Make sure your engine is cool to touch before making pulls. 96mph in the 1/4 means your car was super hot or you were letting it shift on it's own. The factory 3rd shift is too early.

I put down 238hp on a dyno-jet with a 3" downpipe and 258hp after tuning.
I'm 362ish now.

Last edited by DavidGXP; 11-20-2011 at 02:25 PM.
Old 11-17-2011, 09:23 PM
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Well, I let it shift 2nd on it's own but then I put it into M and held 2nd through the traps. Car probably was somewhat hot, though, and I only got 2 runs in that night (1st was 14.3 letting it shift itself into 3rd). Anyways, really only 225? Man I guess I better prepare for that haha. I always thought these were in the 250's stock...
Old 11-18-2011, 11:07 AM
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hold the wheel tight. i braced my arm against the door so the wheels didnt kick when i got on it.
Old 11-18-2011, 03:35 PM
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Run it in 3rd gear
Old 11-18-2011, 04:40 PM
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Don't know what kind of tires you have but the top of 3rd hits 160+ MPH IIRC. Might want to keep that in mind...

It is a longggg pull too depending on where you start and stop, honestly I'd dyno 2nd if you plan on doing a lot of pulls, I would bet your temps stay lower and you can see results all the same if you are just looking for a delta.
Old 11-18-2011, 06:00 PM
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Well my tires are W-rated so I'm not too worried about that part. I'm going to just make 3 pulls since it's part of a dyno day, no tuning involved. I'll probably do at least one run in 3rd and maybe the other 2 in 2nd for temp-sake.
Old 11-19-2011, 01:35 PM
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Update: 241hp and 265tq at the tire. Not too bad for a bone stock GXP right?
Old 11-19-2011, 03:44 PM
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Originally Posted by BlauGXP
Update: 241hp and 265tq at the tire. Not too bad for a bone stock GXP right?
seems like pretty good numbers
Old 11-19-2011, 03:49 PM
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Trap speed > dyno numbers. But your numbers seem to be on par.
Old 11-19-2011, 11:24 PM
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Originally Posted by CenTexSS
Trap speed > dyno numbers. But your numbers seem to be on par.
True.. I dyno'd 238 and trapped 98-99 with a downpipe and no tune. Hot *** engine on the dyno. IAT was over 120 degrees.
Old 11-20-2011, 01:03 AM
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Sounds about right.
Old 11-20-2011, 11:40 AM
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Originally Posted by BlauGXP
Update: 241hp and 265tq at the tire. Not too bad for a bone stock GXP right?
In 2nd or 3rd gear???
Old 11-20-2011, 04:41 PM
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Originally Posted by 1CL3ANSUP3RSPORT
In 2nd or 3rd gear???
I tried both, 3rd gear pull was 235whp and 265wtq, 2nd gear pull was 241whp and 251 wtq, so fairly close:

Old 11-20-2011, 10:27 PM
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Originally Posted by BlauGXP
Update: 241hp and 265tq at the tire. Not too bad for a bone stock GXP right?
I'd say thats right on point. My ISS did 242hp/256tq when it was all stock.




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