whats wrong with this pull >>

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Jun 18, 2010 | 02:08 PM

lsxmalibu

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whats wrong with this pull >>

did 2 pulls, both have the same thing happen at ~4600 rpm.....

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Jun 18, 2010 | 02:15 PM

93sspcoupe

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From: georgia

does the curve have a loop in it going to a lower rpm then a higher one?!?!? looks like it has a nasty miss.

Jun 18, 2010 | 02:42 PM

lsxmalibu

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looks like the engine rpms go down about 100 rpm, then the tq and hp go downhill. On paper that is at about 4600 rpm, but he took it to 5500 and the motor sounded fine.

Jun 18, 2010 | 02:46 PM

93sspcoupe

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From: georgia

if it doesnt miss or anything like that and sounds smooth and clean like you say, then i would have to say the dyno is a pos. put it on a different dyno to see if u get same results

Jun 18, 2010 | 03:07 PM

427LS7HCI

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check your spark plug gaps.

Jun 18, 2010 | 03:16 PM

lsxmalibu

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it was a dyno day, had about 10 cars and mine was the only one.
plugs are gapped at .030", that was about 5psi pull.

Jun 18, 2010 | 03:21 PM

93sspcoupe

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From: georgia

i'd have to say it could be a valve guide problem too. mine did a similar issue on the dyno. guides wore out springs wore out, valves wasnt seating.

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Jun 18, 2010 | 07:42 PM

JPH

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Id keep looking into the tune.

Jun 19, 2010 | 03:36 PM

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lsxmalibu

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I think the tune is close, not perfect but nothing that would cause it to fall off like that

Jun 19, 2010 | 05:28 PM

#11

XtraCajunSS

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From: Baton Rouge, LA, USA

Quote:

Originally Posted by lsxmalibu

I think the tune is close, not perfect but nothing that would cause it to fall off like that

Take a look at torque converter or trans issues. I've seen that type of graph when there are issues in the drivetrain such a clutch or converter slippage.

Shane

Jun 20, 2010 | 10:21 AM

#12

lsxmalibu

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thanks, will do.

Jun 20, 2010 | 06:07 PM

#13

edcmat-l1

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From: Va Beach

CF, DIN is Deutch Industry Standard. Has nothing to do with the shape of the graph.

The loop is a shift, or the converter locking. That's always what it is. Why it looks like **** after the shift is another story.

Jun 20, 2010 | 06:36 PM

#14

Slowhawk

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I agree with a few above.Thats just a bad dyno pull or the converter/tranny messing up.

Jun 20, 2010 | 08:10 PM

#15

lsxmalibu

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its a cheaper converter , no ballon plate, I notice alot of slippage in 3rd gear< rpm go up but mph isnt there.

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