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Dyno question

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Old Aug 30, 2005 | 10:19 PM
  #1  
Hot Rod Hawk's Avatar
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From: Bountiful, Utah
Dyno question

Ok lets try this again, the link should work ok now


Hi guys,
Take a look at my dyno sheet from last weekend. Its my car on 94 octane with a 200 shot. I know the green arrows are a loss of the RPM pick up but what is the wide swing in the osolation [sp?] in the lower rpm [black arrows]?
Did I get into the converter flash on the second pull?


http://www.hotrodhawk.com/livernois1.jpg
Old Aug 30, 2005 | 10:34 PM
  #2  
INTMD8's Avatar
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From: I reached back like a pimp and smacked that LS1....
Re: Dyno question

Could mostly be due to the RPM pickup problem.

Ask them to graph it for you with speed instead of RPM and remove torque. My guess is the graph would be much smoother if just HP vs Speed was shown.
Old Aug 31, 2005 | 01:05 AM
  #3  
MachinistOne's Avatar
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From: Bay Area, CA
Re: Dyno question

It would help to see the air/fuel with that, looks like low speed surge due to a lean AFR. They also ran your motor almost 1k RPM's to high, it stopped making power at 6800 and they ran it to 7600...that's just asking for trouble.

Could also be something with the convertor like you said....If the AFR looks good through there, then thats the next guess.
Old Aug 31, 2005 | 12:53 PM
  #4  
Hot Rod Hawk's Avatar
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Re: Dyno question

I drove the car myself but I did not do the "sample start, sample end" with the remote button, The operator just had me point at him when I wanted to start the sample and he stopped it I gues "when ever".
I logged with TTS on my laptop as well and it shows I lifted at 7000rpm, the same as me watching the Autometer Tach. The dip in the middle of the RPM sweep has also had me thinking... dangrous I know
...the way I have my timing curve set up look's like that's what could be causing the drop in the middle. I have it pulling 4 ~5 degrees in thru there then ramp back in.
WB AFR runs run from 11.5~11.9 thru the RPM.

Last edited by Hot Rod Hawk; Aug 31, 2005 at 12:58 PM.
Old Aug 31, 2005 | 03:30 PM
  #5  
marshall93z's Avatar
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From: Mooresville, NC
Re: Dyno question

200 shot, eh?! Is this a different car than the one we are familiar with?
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