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Could it be ignition problem? Posted by Walt [Email] (#2707) [Profile/Gallery] (more from Walt) on Wed, 4 Dec 2002 19:12:25 In Reply to: Dyno results - needs work (long), Dave D, Mon, 2 Dec 2002 00:16:52 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Just a thought...The consistant erratic behavior above 3800 leads me to speculate there is a rpm related problem somewhere. IMO, detonation could cause this, and so could an ignition miss. But would an ignition problem also affect the A/F readings (more unburnt fuel in exhaust)? Dunno.
In addition, it's interesting to see the power decline happened at identical RPM's in both runs...and significantly after you reach full boost at 3100 rpm. So I'd rule out a problem with the w/g solenoid.
I would think a problem such as excessive back pressure or a too small turbo would give a gradual decline in power, not the erratic behavior you are seeing. It would be interesting to repeat these runs with the timing retarded a few degrees, and with the intake manifold iced down. If it was a detonation problem, this should at least postpone its onset.
I do think you're on the right track with your det. diagnosis.
I would think someone with extensive dyno experience (not me, tho) would be able to lead you in the right direction...
Walt
'88 SPG
'88 base
posted by 209.92.9...
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