Redhawk

Had the 'fox' on the dyno yesterday for the first time and picked up a flat spot which starts at 4000rpm and ends at 4500rpm, the torque and power curves show this funny loop (identical on both curves). Three runs on the dyno and exactly the same little loop.

Any of you guys had this and is there a fix???

Cheers,
Al

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Hypnodoc

ave you been losing sleep Al? Mr Batten and/or GTP-330 are probably the best to seek advice from mate

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Xtreme F6

I would need to see the dyno sheet to make a comment but im guessing as apposed to an actual flat spot its more than likely a point of either the manifold or the pipes or even cams going on or off tune...On the GT for example theres a spot on the dyno graph where its point of climbing tapers of a little then starts to climb again. Changing headers on a GT will actually make this LUL as i like to call it lift up a bit in KWs but it in itself will remain in the same position.(same rev range)...

aps

Mate it could be knock sensor operation, the computer may be retarding ignition timing around the peak torque area. Try some good octane booster if this improves the power dip in the dyno graph, then you can be sure that the original dip in the power graph was ignition timing related. Worth a try for your own peace of mind.

Peter

APS

GT-P

Looks like a roller coaster ride....

Did those guys use the dyno correctly, I havn't seen anything like that before.

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HSV

Haven't seen the dyno, but sounds very much like a case of valve bounce.

Regards.

Redhawk

Now I'm worried!

From what I saw Barry, yes he had set the dyno up correctly.

Will ring you later today.

Al

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Adventra

When mine was dynoed, its curve is one nice long gradual increase, mine seems to be strong at the 4k mark. Id be looking into it, as Peter said, look at the fuel and boost it if you think its down.

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Redhawk

Thanks for the posts guys,

I personally reckon the dyno is the fault, cannot feel any flat spot when driving the car, she powers through 4000 - 4500 range in 1st, 2nd & 3rd (have'nt taken her on the highway to check 4th.........yet!).

Getting her checked at D & T Performance on Wed, will let you know the results!

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Vixen GT, Build No 665 (Damn! one off!!), Tremec Short Shifter, Premium Sound, FPV Steering Wheel, Tint, Stripes. In my garage!
FPVTickford Owners Club of WA

Xtreme F6

lol @ 4000rpm???? dont think so dude....nah its going to be a case of dyno me thinks.. Its ok its booked in to D&T for a run on wed i believe .. Ill meet you there and have a chat