dyno testing
Thread Starter
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Junior Member
Joined: May 1999
Posts: 8
Likes: 0
From: SMYRNA, GA USA
dyno testing
How is everyone getting their dyno numbers? I had mine dyno'd last week and the way the guy was doing it didn't make me feel comfortable about the numbers. He accelerated thru 1st and 2nd gears then when it shifted into 3rd gear he started testing. Is this the normal way to do it? He admitted that he doesn't get many automatics and we did 8 dyno runs and none were even close to being the same. The rpm's after the 2-3 shift were already 3300rpm. My graph goes from 3300rpm to 5600rpm..
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1999 White Lightning
Nitrous,Sal's Chip&Airfilter
3.73,blower pulley,racing slicks(when needed)
SHM massair(un-installed)
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1999 White Lightning
Nitrous,Sal's Chip&Airfilter
3.73,blower pulley,racing slicks(when needed)
SHM massair(un-installed)
Really Old "Member"
Joined: May 1999
Posts: 1,362
Likes: 0
From: Kennesaw, Ga. USA
Hey Billy:
1. Where in Atlanta are you located?
2. Where did you get your dyno test done?
3. Mine was done in Marietta just off exit 112. Haven't got the card handy and I forget the name of the place, but it was next to a speed shop.
4. My dyno guy did the same (3d gear pulls) as we could not stop down shifting in 1st and second. My graph starts at about the same rpm as yours. It probably doesn't mean anything to horsepower, but may hurt the torque number as it starts awfully high.
5. I got Sal's air filter today, and maybe we could meet if you are near Marietta. I am not a wrench, and the instructions were clear, but "NO PICTURES" to speak of. I like pictures!
I am leaving for Chicago tomorrow and returning next Sunday. Drop me an e-mail at MOSTOYSINC@AOL.Com or htuken@BellSouth.net if we can get together.
Bill Murray
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Bill Murray
99.5 Lightning
Oxford White
Bedrug/ARE LSII lid
Tow Package CD Player
Superchip
HobbyTownUSA Graphics
Identical 1/10 Scale Tamiya RC Truck incl. graphics.
Truck interest e-mail:
fastwhitey@myf150.com
4 heavy decals!
Kennesaw (Atlanta) Ga.
1. Where in Atlanta are you located?
2. Where did you get your dyno test done?
3. Mine was done in Marietta just off exit 112. Haven't got the card handy and I forget the name of the place, but it was next to a speed shop.
4. My dyno guy did the same (3d gear pulls) as we could not stop down shifting in 1st and second. My graph starts at about the same rpm as yours. It probably doesn't mean anything to horsepower, but may hurt the torque number as it starts awfully high.
5. I got Sal's air filter today, and maybe we could meet if you are near Marietta. I am not a wrench, and the instructions were clear, but "NO PICTURES" to speak of. I like pictures!
I am leaving for Chicago tomorrow and returning next Sunday. Drop me an e-mail at MOSTOYSINC@AOL.Com or htuken@BellSouth.net if we can get together.
Bill Murray
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Bill Murray
99.5 Lightning
Oxford White
Bedrug/ARE LSII lid
Tow Package CD Player
Superchip
HobbyTownUSA Graphics
Identical 1/10 Scale Tamiya RC Truck incl. graphics.
Truck interest e-mail:
fastwhitey@myf150.com
4 heavy decals!
Kennesaw (Atlanta) Ga.
Senior Member
Joined: Aug 1999
Posts: 166
Likes: 0
From: Northville, MI USA
Dyno testing, whether with a manual or automatic, is done in a gear with a 1.00:1 gear ratio. On your Lightning, that would be third gear. The engine is lugged down to the lowest rpm possible without the transmission downshifting into the next lower gear on acceleration. It takes some practice to get it right.
Did you manage to get at least one of the runs in 3rd gear without the transmission downshifting? If so, I would use the power numbers from that run.
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HotRodSix
'98 STX Flairside 4.2L
Did you manage to get at least one of the runs in 3rd gear without the transmission downshifting? If so, I would use the power numbers from that run.
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HotRodSix
'98 STX Flairside 4.2L
Former Sponsor
Joined: Mar 1998
Posts: 13,385
Likes: 4
From: Virginia
Dear Billy,
For chassis dyno runs made on automatics, you need to program the vehicle to stay in gear, so that it doesn't downshift. Most chassis dyno plots don't even start until 2000 rpm or so, as that is about the lowest rpm at which they can get stable readings on the dyno. I'm sure you're dyno operator probably did all he could do under the circumstances.
Good luck,
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Mike Troyer
Performance Products, Inc.
National Distributor of Superchips
(540) 862-9515
Email: mtroyer@compuserve.com
For chassis dyno runs made on automatics, you need to program the vehicle to stay in gear, so that it doesn't downshift. Most chassis dyno plots don't even start until 2000 rpm or so, as that is about the lowest rpm at which they can get stable readings on the dyno. I'm sure you're dyno operator probably did all he could do under the circumstances.
Good luck,
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Mike Troyer
Performance Products, Inc.
National Distributor of Superchips
(540) 862-9515
Email: mtroyer@compuserve.com