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Old 12-08-2011, 12:35 AM   #1
Jeff Lee
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Default Re: 60ft issues

I would suggest it appears you lost a lot of HP between the dyno and the track. ;(
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Old 12-08-2011, 03:30 AM   #2
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Default Re: 60ft issues

Quote:
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I would suggest it appears you lost a lot of HP between the dyno and the track. ;(
Exactly my thoughts. How much weight are you hauling?
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Old 12-08-2011, 10:31 PM   #3
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Default Re: 60ft issues

The car weighs 3500 pounds and RWR power .All steel.

Last edited by CamCam; 12-08-2011 at 10:34 PM.
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Old 12-08-2011, 11:06 PM   #4
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Default Re: 60ft issues

Cam Cam our best 60' is 1.42 10.9 @ 120. 3150# with a little weight in the rear bumper. 5.86 [ was about the same with 5.57 ] 3.2 1st in transmission .84 Trans Am body probably worth a little MPH. We also have AVO shocks about the same settings. MT 29.5 9 slicks 12 lbs. warm . Lighter springs in the pp really helped---Trevor
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Old 12-08-2011, 11:11 PM   #5
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Default Re: 60ft issues

If the dyno is correct, 690 HP would be around 135 MPH. That's 5-6 more than you are showing. Fixing the clutch or traction issues isn't going to bring the MPH up much, if any. So the bottom line is, something is amiss in the HP department of the vehicle. That could is typically ignition or fuel issues. As an example, you will feed plenty of fuel to the engine while it is on the dyno because there's nothing to cause problems. But if the fuel system is not able to keep up with the engine while under a heavier load, or the system can't push enough fuel through the system, then your HP will be cut drastically. And in your case, I see 75+ missing. That's significant.
My suggestion is to find the missing HP which will cure the low MPH issue. Then you can work on the rest of the car.
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Old 12-08-2011, 11:35 PM   #6
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Default Re: 60ft issues

Well i don't think rick waters lied about the figures, we know there is a gremlin in the chassis. But do appreciate the advice. We will keep searching.



Quote:
Originally Posted by Jeff Lee View Post
If the dyno is correct, 690 HP would be around 135 MPH. That's 5-6 more than you are showing. Fixing the clutch or traction issues isn't going to bring the MPH up much, if any. So the bottom line is, something is amiss in the HP department of the vehicle. That could is typically ignition or fuel issues. As an example, you will feed plenty of fuel to the engine while it is on the dyno because there's nothing to cause problems. But if the fuel system is not able to keep up with the engine while under a heavier load, or the system can't push enough fuel through the system, then your HP will be cut drastically. And in your case, I see 75+ missing. That's significant.
My suggestion is to find the missing HP which will cure the low MPH issue. Then you can work on the rest of the car.
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Old 12-09-2011, 02:13 PM   #7
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Default Re: 60ft issues

Quote:
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Well i don't think rick waters lied about the figures, we know there is a gremlin in the chassis. But do appreciate the advice. We will keep searching.
If you re-read my post, I didn't say the dyno HP is a lie. I'm saying the HP got lost on the way to the track. Don't take it personal, it happens a lot. Fuel, ignition, gearing, hood clearance, etc., there are many ways to loose power.
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Old 12-09-2011, 09:14 PM   #8
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Default Re: 60ft issues

How much tq.@ what rpm does tq.&hp peak@.
I don't know anything about your combo, but I would guess launch is too low,clutch probaly too tight, 4.88 gear too high. it's choked down.
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Old 12-08-2011, 11:38 PM   #9
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Default Re: 60ft issues

What's the transmission gearing? Where are you shifting it and what's the rpm at the finish line??? I'm having a problem seeing how a 3,500 lbs car with a small block making 690 needs a 4.88 gear.
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