Trouble shooting... down on power
08-01-2006, 01:17 PM
#1
Trouble shooting... down on power My current combo is in sig, I dyno'd 400 rwhp @ 6,000 and 376 rwtq @ 4,700. I do have a 12 bolt but still I should have 425 or so hp at the wheels. Car is an MN6 and dyno numbers are corrected.
Current thoughts are:
- exhaust is too restrictive (2.5" y pipe and borla solid plate is in)
- fuel pump needs to be replaced (original with 47k miles on it)
Otherwise, not sure what the deal is but I'm disappointed in my numbers. Any help would be greatly appreciated.
Current thoughts are:
- exhaust is too restrictive (2.5" y pipe and borla solid plate is in)
- fuel pump needs to be replaced (original with 47k miles on it)
Otherwise, not sure what the deal is but I'm disappointed in my numbers. Any help would be greatly appreciated.
08-01-2006, 01:39 PM
#2
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put it on the track.
12.2 BEFORE heads and pulley is a decent time. Don't get to caught up in the numbers themselves. Some cars dyno lower than others yet have great track times.
My car for example. COMPLETELY stock with 18's as the only modification ran 12.875 @113mph. Then with the 224/112 tr cam and slp junk w/cats and radials only, car did 12.1 @ 120mph BUT I had only 367rwhp.
Take it to the track.
12.2 BEFORE heads and pulley is a decent time. Don't get to caught up in the numbers themselves. Some cars dyno lower than others yet have great track times.
My car for example. COMPLETELY stock with 18's as the only modification ran 12.875 @113mph. Then with the 224/112 tr cam and slp junk w/cats and radials only, car did 12.1 @ 120mph BUT I had only 367rwhp.
Take it to the track.
08-01-2006, 03:18 PM
#3
I agree with you to an extent, but one thing I failed to add above was that I only gained 22 rwhp and 25 rwtq with the addition of heads and pulley. The only variable was in the interim time period I also changed from hooker long tubes with 3" ORY to dynatech long tubes with 2.5" ORY. I'm guessing that killed some power that would have otherwise shown up on the dyno comparo. Both runs were on the same dyno and corrected, so there's no dyno variables at play here.
08-01-2006, 05:07 PM
#4
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what was the air temp? controlled enviroment? What about fuel delivery, you might be leaving some on the table by running stock everything (if thats what you have)
The more power you have the larger number you WONT see because of the rear also. That rear is sucking up a % of the amount of power comming out of the motor/trans.
Lets say 15% loss. At 300hp BEFORE the rear and trans - 255 after, Now with 450hp BEFORE the rear and trans - 382.5 after. I still say put it on the track.
The more power you have the larger number you WONT see because of the rear also. That rear is sucking up a % of the amount of power comming out of the motor/trans.
Lets say 15% loss. At 300hp BEFORE the rear and trans - 255 after, Now with 450hp BEFORE the rear and trans - 382.5 after. I still say put it on the track.
08-01-2006, 05:38 PM
#5
Originally Posted by 01350ss
what was the air temp? controlled enviroment? What about fuel delivery, you might be leaving some on the table by running stock everything (if thats what you have)
The more power you have the larger number you WONT see because of the rear also. That rear is sucking up a % of the amount of power comming out of the motor/trans.
Lets say 15% loss. At 300hp BEFORE the rear and trans - 255 after, Now with 450hp BEFORE the rear and trans - 382.5 after. I still say put it on the track.
The more power you have the larger number you WONT see because of the rear also. That rear is sucking up a % of the amount of power comming out of the motor/trans.
Lets say 15% loss. At 300hp BEFORE the rear and trans - 255 after, Now with 450hp BEFORE the rear and trans - 382.5 after. I still say put it on the track.
I'm going to the track Friday night, we'll see what happens... If I don't run 11s and I'm going to be pissed.
