Dynoed...disappointment
Thread Starter
Instructor
Joined: Feb 2012
Posts: 125
Likes: 0
Dynoed...disappointment
Over the weekend, I went to the Tulsa Street Car meet and participated in their dyno marathon.
I made two 4th gear runs on a dynojet. This equates to a loss of 17 WHP and 30 WTQ since the last dyno run I did a few years back.
The car was strapped on the dyno after a 2 hour drive to Tulsa with no cool down period, so you can imagine that the engine was at its maximum operating temp when I made the runs.
My old dyno #: 473whp/424wtq
New dyno #: 456whp/394wtq
I am thinking the test conditions has a big part in the lower #s. Old dyno run was performed in California cool 69 degree weather and new dyno run in 91 degree weather. Could the high temperature be the main sole cause of the drop?
Besides the test conditions, other things that have changed on the car since the 1st dyno run:
1. added Halltech Flow Straightener honeycomb screen to the MAF
2. changed LS7 clutch setup to a lighter monster level 2 setup with lightened flywheel
3. added catch can
4. Switched from 5-30 oil to Mobil 1 0-40
5: added 10,000 miles to the engine
Does anyone believe that any of the above could affect the #s in a significant way?
For fun, here is a clip of my dyno run
:
I made two 4th gear runs on a dynojet. This equates to a loss of 17 WHP and 30 WTQ since the last dyno run I did a few years back.
The car was strapped on the dyno after a 2 hour drive to Tulsa with no cool down period, so you can imagine that the engine was at its maximum operating temp when I made the runs.
My old dyno #: 473whp/424wtq
New dyno #: 456whp/394wtq
I am thinking the test conditions has a big part in the lower #s. Old dyno run was performed in California cool 69 degree weather and new dyno run in 91 degree weather. Could the high temperature be the main sole cause of the drop?
Besides the test conditions, other things that have changed on the car since the 1st dyno run:
1. added Halltech Flow Straightener honeycomb screen to the MAF
2. changed LS7 clutch setup to a lighter monster level 2 setup with lightened flywheel
3. added catch can
4. Switched from 5-30 oil to Mobil 1 0-40
5: added 10,000 miles to the engine
Does anyone believe that any of the above could affect the #s in a significant way?
For fun, here is a clip of my dyno run
:Last edited by Vette Moto; Aug 18, 2013 at 01:13 PM.
Thread Starter
Instructor
Joined: Feb 2012
Posts: 125
Likes: 0
I was thinking it was that too...
here are my mods:
-TFS(Trick Flow) 215 Heads
-Custom Cam 228/232 115 LSA +4 XER
-Injectors (Bosch)
-Ported Fast 92 w/big mouth Throttle Body
-Custom pushrods 7.500 for TFS(Trick Flow) heads
-American racing headers 1-3/4 w/cats
-NGK plugs and high performance 10.4mm wires
-Corsa Extreme exhaust w/ Corsa x-pipe
-Head and cam Dynotune
-50th Anniversary carbon fiber airduct and dual cone intake
-Monster level 2 clutch with 18 lb. Monster flywheel
here are my mods:
-TFS(Trick Flow) 215 Heads
-Custom Cam 228/232 115 LSA +4 XER
-Injectors (Bosch)
-Ported Fast 92 w/big mouth Throttle Body
-Custom pushrods 7.500 for TFS(Trick Flow) heads
-American racing headers 1-3/4 w/cats
-NGK plugs and high performance 10.4mm wires
-Corsa Extreme exhaust w/ Corsa x-pipe
-Head and cam Dynotune
-50th Anniversary carbon fiber airduct and dual cone intake
-Monster level 2 clutch with 18 lb. Monster flywheel
Race Director
Joined: May 2012
Posts: 15,752
Likes: 3,267
From: Phoenix area, AZ
The 22 degree temp difference could most certainly cause a drastic change in the dyno results. Cooler, and thus more dense air adds more HP while hot air robs it. If you ever watch the NHRA Spring and Fall Nationals you will see huge HP differences in the same car. The same goes for the races up in Colorado, which has cooler, but much thinner air.
Burning Brakes
Joined: Dec 2003
Posts: 1,243
Likes: 5
From: Loveland CO
- Outside air temps and Humidity
- 700ft elevation change (Sea Level to Tulsa OK)
- Engine Opperating temps
- Calibration of Dyno (some are more generious then others)
Dont sweat it. Ohh and dont dyno in CO... lol that would put the nail in your coffin
S
- 700ft elevation change (Sea Level to Tulsa OK)
- Engine Opperating temps
- Calibration of Dyno (some are more generious then others)
Dont sweat it. Ohh and dont dyno in CO... lol that would put the nail in your coffin
S
Burning Brakes
Joined: Nov 2001
Posts: 1,163
Likes: 19
From: Not far from COTA
dynos are very different, so don't be concerned
the main issue is are you happy with your car and it's performance?
my car dynoed 329hp on one and then later 379 on another
no mods at all and no changes between them
dynos lie
the main issue is are you happy with your car and it's performance?
my car dynoed 329hp on one and then later 379 on another
no mods at all and no changes between them
dynos lie
Safety Car
Joined: Oct 2004
Posts: 4,816
Likes: 132
From: Plano TX
I've seen some flat out crazy numbers on different dynojets over the last 10 years.. Tummsvette in our Collin County Club put down 350rwhp and 1320rwtq a few weeks ago.. LS1 with bolt ons.. The 350rwhp was in the ball park but the 1320 rwtq was a laugh! Eric.. Please post your dyno sheet .... The results look like a Mack Truck Dyno!!
Last edited by David426; May 21, 2012 at 11:53 PM.
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