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what gear to dyno in ???

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Old Dec 18, 2004 | 10:50 AM
  #31  
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Originally Posted by BlownChevy
Ahh the dyno argument....I have not seen this one in a while
Gotta rehash the old stuff for the noobies
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Old Dec 18, 2004 | 10:52 AM
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reverse.
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Old Dec 18, 2004 | 01:46 PM
  #33  
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Originally Posted by Naked AV
I'm with you. I had no idea the dyno operator was going to run my truck in 3rd, and ignorant as I was, I assumed it would be 2nd. There were people standing 12-15 ft from my truck when the driveshaft came apart at 141 mph, and half of the shaft flew out and came to rest about 2 feet from one of the bystanders. I felt thumps under the floorboards when it split in half, before it separated from the front U-joint. Pretty scary ****. We were all very fortunate that no one was hurt.

That incident changed how I look at speed and also how I look at professionals who are supposed to know what they're doing. Going forward, I will not trust anyone to do my thinking for me. From now on I will be doing all of my own research, like I should have been doing in the first place, like I already do in other areas like law (lawyers) and medicine (doctors).

As far as dynoing my vehicle, any future runs will be done in second gear. I pretty much have to with a 5" x 72" aluminum driveshaft and its associated critical speed. I don't care if it shows less power. I will also be standing very far away and/or behind something from for my vehicle's and all other's dyno runs. All it would take would be some manufacturing defect in the rear end or a nail in a tire to show itself at 125 or 130 mph, and someone loses a limb, an eye, or their life.

My $.02.
I might just go ahead and use my Gtech from now on. Especially if all I get is an est. HP # from a second gear pull, I believe Parish has shown the Gtech to be impressively accurate. Also, in some cases it might be more accurate based on the computed variables and might actually reflect more "real world", where the rubber meets the road #'s compared to a 2nd gear run. The added benefit being, I'm the one stomping the gas. I'll conduct some more baselines in the morning
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Old Dec 18, 2004 | 04:01 PM
  #34  
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Originally Posted by BlownChevy
Ahh the dyno argument....I have not seen this one in a while
Completely different discussion, actually, but thanks for your worthy contribution to the thread/discussion.
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Old Dec 19, 2004 | 01:26 PM
  #35  
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Collecting data is tuff around here, sheesh. Finally found a deserted FLAT street to make some Gtech runs on.

1/4 mile ET 15.7 @ 90.9mph
60ft 2.3
0-60 8.1
1/8 mile ET 10.2 @ 71.3mph

245 hp @ 5166rpm
260 tq @ 3825rpm

for those that have studied ET/HP, how does this sound?
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Old Dec 19, 2004 | 02:21 PM
  #36  
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FWIW here is what I got for mine with the Superchips 2280 but with the Air Force One Intake removed.

1/4 mile ET 16.19 @ 89.5 mph
60 Ft 2.63
0-60 8.7
1/8 mile ET 10.6 @ 70.4 mph

234 HP @ 4624 rpm
278 TQ @ 4052 rpm

My truck weighs 6050 lbs with me in it but I cannot remember how much gas. The run was done in 4HI and I think the HP and TQ figures are from 2nd gear because the trans always shift down on me if I try to do a 3rd gear pull.
These figures are an average of 4 runs taken on May 4, 2004 at 12*C ( 54* F) at about 100 Ft above sea level.
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Old Dec 19, 2004 | 04:03 PM
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Originally Posted by Mort
FWIW here is what I got for mine with the Superchips 2280 but with the Air Force One Intake removed.

1/4 mile ET 16.19 @ 89.5 mph
60 Ft 2.63
0-60 8.7
1/8 mile ET 10.6 @ 70.4 mph

234 HP @ 4624 rpm
278 TQ @ 4052 rpm

My truck weighs 6050 lbs with me in it but I cannot remember how much gas. The run was done in 4HI and I think the HP and TQ figures are from 2nd gear because the trans always shift down on me if I try to do a 3rd gear pull.
These figures are an average of 4 runs taken on May 4, 2004 at 12*C ( 54* F) at about 100 Ft above sea level.
Our info looks very similiar. I'm at 5800lbs with a 1/2 tank & me in it. All I have is a Cat Back Magnaflow. I love this little device
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Old Dec 19, 2004 | 04:05 PM
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Forgot to mention, I was launching from a brake stalled 2500rpms.
One time she broke loose and laid a 30ft patch
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Old Dec 19, 2004 | 07:48 PM
  #39  
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I sort of brake stall as well. I put my foot on the brake and floor it and when the revs go over 2200 or so I let up on the brake. I get both rear tires spinning for about 10 feet then they hook up. I never measured it so 10 ft is just a guess. Sometime I will just hold it and see where it stalls.

Later
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Old Dec 19, 2004 | 07:54 PM
  #40  
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Originally Posted by moregrip
Collecting data is tuff around here, sheesh. Finally found a deserted FLAT street to make some Gtech runs on.

1/4 mile ET 15.7 @ 90.9mph
60ft 2.3
0-60 8.1
1/8 mile ET 10.2 @ 71.3mph

245 hp @ 5166rpm
260 tq @ 3825rpm

for those that have studied ET/HP, how does this sound?
SHEESH!!
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