what gear to dyno in ???
12-17-2004 | 12:29 AM
#11
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what a rush!
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From: Las Vegas, NV
Originally Posted by parish8
3rd in my truck is about 160 so i dyno in 2nd.
with edit you can set up your tow haul for the dyno. when i hit the tow haul the tranny shifts into 2nd at 10mph and locks up at about 15mph and stays there no matter what. it works great on the dyno and i have used it a few times while tuning some of the fueling in places(rpm and load) that you dont see everyday.
with edit you can set up your tow haul for the dyno. when i hit the tow haul the tranny shifts into 2nd at 10mph and locks up at about 15mph and stays there no matter what. it works great on the dyno and i have used it a few times while tuning some of the fueling in places(rpm and load) that you dont see everyday.
12-17-2004 | 12:35 AM
#13
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Joined: Mar 2004
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From: Sun Diego
As some of you know, my 3rd gear run ended in a broken driveshaft... 5800+rpms@141mph ... whether this was a result of a poorly balanced stock driveshaft, critical speed being reached, or whatever, I'll likely do all my future dyno runs in 2nd.
12-17-2004 | 12:37 AM
#14
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From: Las Vegas, NV
Originally Posted by Naked AV
As some of you know, my 3rd gear run ended in a broken driveshaft... 5800+rpms@141mph ... whether this was a result of a poorly balanced stock driveshaft, critical speed being reached, or whatever, I'll likely do all my future dyno runs in 2nd.
12-17-2004 | 10:56 AM
#18
Originally Posted by F8L Z71
There is no sense in dynoing in 3rd gear when you can easily do it in 2nd gear and do the convertion and it will come out very close if not identical to a 3rd gear pull 
moregrip, your last dyno covered both 2nd and 3rd gears. It shows the complete 2nd gear pull, the 2-3 shift, then part of 3rd until you hit the speed limiter.
Moregrip Dyno
12-17-2004 | 11:04 AM
#19
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From: Las Vegas, NV
Originally Posted by BigTex
Thats just like running the 1/8th mile and applying a 1/4 mile conversion factor to it. It will be close, but its not the same as running a 1/4 and knowing the truth. If you want numbers that are pretty close but not exact, try a GTECH. Why even mess with a dyno at all?
moregrip, your last dyno covered both 2nd and 3rd gears. It shows the complete 2nd gear pull, the 2-3 shift, then part of 3rd until you hit the speed limiter.
Moregrip Dyno
moregrip, your last dyno covered both 2nd and 3rd gears. It shows the complete 2nd gear pull, the 2-3 shift, then part of 3rd until you hit the speed limiter.
Moregrip Dyno
OK, is 135mph safe? I know my tires are rated for something like 186mph.
My driveshafts are steel and 2 pc........any other considerations?
12-17-2004 | 11:05 AM
#20
12 Second Truck Club
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From: Sacramento, CA
I don't see your logic Tex. I have seen lots of cars dyno'd in 2nd gear then in 3rd gear and they are always VERY close. I think your 1/8th mile to 1/4mile analogy is a lil on the extreme side as there are too many variations there. Besides, some dyno's are set up to run in 2nd gear under normal circumstances but can easily switch back and forth. All a dyno does is make calculations and there are correction factors for everything already, changing one isn't going to effect much IMO.
If we wanna get technical about being 100% accurate then people better quite wasting their time on dynojets because those #s are always inflated. Better yet, we better do more research on the places we dyno and figure out what correction factors they used and collect the weather data so we can compare HP that way because without that data all our #s are not truely comparable.
But by all means if you wanna run a truck to 160mph or something wild on the dyno go for it LOL
If we wanna get technical about being 100% accurate then people better quite wasting their time on dynojets because those #s are always inflated. Better yet, we better do more research on the places we dyno and figure out what correction factors they used and collect the weather data so we can compare HP that way because without that data all our #s are not truely comparable.
But by all means if you wanna run a truck to 160mph or something wild on the dyno go for it LOL