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Dyno

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Old Apr 24, 2004 | 12:02 PM
  #1  
hoffa's Avatar
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From: texas
Dyno

i dynojetted my car and i am sorry to say i was dissapointed. i thought i would have more hp/torque. and i ran it on 5th gear.

MAX HP= 162.68
MAX TQ= 125.63

run conditions:
80.14 F, 29.38 in-Hg, SAE: 1.03
Run type: RO


few questions:
why did my ABS light go off?? does that affect my dyno and it seems to me that the car SHOULD BE putting out like 185 on the dynos or 195 to make it equal 247? please any info or help would be greatly appreciated.

P.S. the guys at the place i dynoed my car said that he doubted that our car was making 247, he thinks its making like 210 with the specs my car shot out.

Last edited by hoffa; Apr 24, 2004 at 12:14 PM.
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Old Apr 24, 2004 | 01:08 PM
  #2  
GiN's Avatar
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From: LA/OC/LV
Perhaps a run in lower gear might help.
Although I'm not too keen on the specifics of dyno'ing, I've gotten a peak of 186hp in 4th gear and 183hp in 3rd gear (not sure about torque or at what rpm because they were doing HP vs MPH)
The ABS light shouldn't go off, but DSC should be disabled otherwise the engine's computer won't appreciate the rear wheels spinning while the front wheels are stationary.
I've also read somewhere on this forum that the newest pcm flashes increase the vehicle's torque but may lower hp...
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Old Apr 24, 2004 | 04:36 PM
  #3  
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From: texas
we did it once on 4th gear, and i got 156hp, then they checked the net and they said 5th gear was the best to do dyno according to the gear ratio's.. but i wonder why i got 162 dam thats low
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Old Apr 24, 2004 | 06:37 PM
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From: Idaho, Home of McDonalds Fries
I've read third gear is the best for dyno.

Also if your ABS light came on your car might have gone in to "limp mode".

When the car has a problem the computer reduces power so you can "limp" home.
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Old Apr 24, 2004 | 07:05 PM
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From: Nashville, TN
Sounds like limp mode, from everything I've read here and other places, as well as what I've been told from more experienced tuners, with the quarter mile times the car should be putting down close to 200 at the wheels, give or take a few hp. The computer apparently richens the fuel mixture when the back wheels are spinning and the front aren't at higher rpm's, therefore the drop on power.

Lot's of people here don't believe it, but I've seen time slips that physically prove it wrong.
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Old Apr 24, 2004 | 10:29 PM
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The car detects that the front wheels are not turning and goes into limp mode. You need to crawl under the rear, remove the one bolt on each rear wheel that holds in the ABS sensor, carefully pull out the sensor and tie it up out of the way. Then do your dyno run(s). Make sure no run lasts longer than 10 sec. or so, otherwise the EPS will put you into limp mode. Before driving off the dyno, replace the ABS sensors (or you will go into limp mode because the front wheels will be turning but not the rear .

Yes, the HP you saw was low. You should see about 180 HP (about 200-210 at the engine). Yes, it's less than 247. Yes, it's less than the current claim by Mazda of 238. Gee, it's 10% less, exactly the minimum allowed. Wonder how that happened?

Last edited by RX-8 friend; Apr 24, 2004 at 10:32 PM.
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Old Apr 25, 2004 | 12:42 AM
  #7  
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From: Florida
Re: Dyno

Originally posted by hoffa
i dynojetted my car and i am sorry to say i was dissapointed. i thought i would have more hp/torque. and i ran it on 5th gear.


P.S. the guys at the place i dynoed my car said that he doubted that our car was making 247, he thinks its making like 210 with the specs my car shot out.
check this out:
https://www.rx8club.com/showthread.p...threadid=26085
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Old Apr 25, 2004 | 02:29 AM
  #8  
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From: Nashville, TN
I'm in agreement with what the above say, fooling the ABS or not, I believe it is still richening the upper RPM's as I mentioned, by the laws of physics, with the 1/4 mile times and trap speeds, it should be putting down about 205 or so at the wheels.
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Old May 2, 2004 | 12:33 PM
  #9  
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From: montreal
Re: Dyno

Originally posted by hoffa
i dynojetted my car and i am sorry to say i was dissapointed. i thought i would have more hp/torque. and i ran it on 5th gear.

MAX HP= 162.68
MAX TQ= 125.63

run conditions:
80.14 F, 29.38 in-Hg, SAE: 1.03
Run type: RO


few questions:
why did my ABS light go off?? does that affect my dyno and it seems to me that the car SHOULD BE putting out like 185 on the dynos or 195 to make it equal 247? please any info or help would be greatly appreciated.

P.S. the guys at the place i dynoed my car said that he doubted that our car was making 247, he thinks its making like 210 with the specs my car shot out.
Reply
Old May 2, 2004 | 03:07 PM
  #10  
r0tor's Avatar
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From: PA
a) you went into limp mode
b) 5th gear should give you the best hp since thats the 1:1 ratio gear
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