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OK Dyno experts....Little wisdom here?

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Old 10-01-2003, 06:00 PM
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Default OK Dyno experts....Little wisdom here?

Ok, I have the mods listed below. I took my car to get it tuned. The guy who tuned it is very good and squeezed a fair amount out of it. I was expecting about 385-390 HP....Instead I got:

HP 367
TQ 461

OK, I was dissapointed int he HP, number, but 461 TQ? I have never seen this kind of imbalance in tq/hp numbers. I know some is due to the converter, but 367/461??

Can anybody take a guess at this one?
Old 10-01-2003, 06:05 PM
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Default Re: OK Dyno experts....Little wisdom here?

Let's see the graph, something doesn't sound right...
Old 10-01-2003, 06:11 PM
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Default Re: OK Dyno experts....Little wisdom here?

Those numbers look like they came from a 5.0 mustang on nitrous. Something is definately screwy.
Old 10-01-2003, 06:14 PM
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Default Re: OK Dyno experts....Little wisdom here?

That's what I thought. Never seen a dyno result like that. I will try to get the chart scanned tom. Basically, there is a huge spike up in the tq curve at the stall, then it slowly dies off and crosses over at very high rpm. The HP curve is a very steady climb up to the peak. I have never seen a dyno graph out of a LS1 like this and am very curious as to what is causing it....

Old 10-01-2003, 06:17 PM
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Default Re: OK Dyno experts....Little wisdom here?

I think that Torque is determined from your HP by a equation-related-factor. Maybe it is possible that the calibration for that factor was screwed up in the software.
Old 10-01-2003, 06:21 PM
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Default Re: OK Dyno experts....Little wisdom here?

I thought the same thing also,but this guys dyno's LS1's very regularly and no other results seemed to indicate that there was any problem. One thought was that the mac's/cats/egr,etc might be killing the HP number and that the tq number is correct?

I am out of ideas. I took 8 runs during tuning and all produced the same pattern in the dyno chart with massive tq numbers and so-so HP numbers. With the mods listed, I 've got to think something is wrong-limitting the hp?
Old 10-01-2003, 06:31 PM
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Default Re: OK Dyno experts....Little wisdom here?

Your high torque is probably do to the torque spike and torque converter. Without locking the converter on the dyno it is hard to gauge how much torque your car actually makes, You can also look at the graph to see where the curve should peak and check the torque there; unless your stall converter is still effecting that area.

As for the low power... I dunno.
Old 10-01-2003, 06:53 PM
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Default Re: OK Dyno experts....Little wisdom here?

it is definately a tq spike. the dyno operator didnt dyno correctly. you need to dyno in 3rd gear and not allow it to downshift back down into 3rd. teh convertor makes for the spike and the motor doesnt make that.
Old 10-01-2003, 08:37 PM
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Default Re: OK Dyno experts....Little wisdom here?

yeah, converter spike, see what the tq is at 4800-5000rpms, thats where most peak... the hp and tq should cross at 5250... u must dyno with the converter locked... u should pick up about 15-20hp with the converter locked, but with a 224 cam, stage 2 heads and the other stuff, u should be at 400 at least... try again with it locked and see...
Old 10-02-2003, 03:16 AM
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Default Re: OK Dyno experts....Little wisdom here?

Thanks guys, that makes sense. Appreciate the input.




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