Dyno numbers air temp question...
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From: Port Tobacco, MD
Dyno numbers air temp question... I know there has always been high rwhp cars that have been questioned. How many of you guys have checked the IAT temps vs the shop temps?
Since most dyno with the hoods open, IATs tend to follow ambient temps. Whether ambient temps mimick what's entered into the correction factor is always a point to debate though.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
Thread Starter
7 Second Club
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From: Port Tobacco, MD
The reason I as is, we recently had a car dynoed locally that dynoed @ at a shop who is known for big dyno numbers. The car dynoed close to 500rwhp and 440rwtq when the package was built less than a couple of months ago. When the car goes on the rollers here, it lays down a less than exciting 458/401. The owner was pissed but IMO they are strong numbers. Either the car lost 40/40, which the owner says it runs the same as before or the dyno correction factors can be manipulated.
Originally Posted by Phil99vette
The reason I as is, we recently had a car dynoed locally that dynoed @ at a shop who is known for big dyno numbers. The car dynoed close to 500rwhp and 440rwtq when the package was built less than a couple of months ago. When the car goes on the rollers here, it lays down a less than exciting 458/401. The owner was pissed but IMO they are strong numbers. Either the car lost 40/40, which the owner says it runs the same as before or the dyno correction factors can be manipulated.
Bruce
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From: Omaha, NE
Our dyno is located in an area where we probably have as much of a variation in atmospheric conditions as anywhere, yet our atmospheric correction factors seem to be amazingly accurate on NA cars. With boost applications, the higher corrections on a hot, steamy day seem to help their numbers because they create their own atmosphere to some degree, but not using corrections at all make it worse even less accurate.
A vehicles measured IATs usually run slightly higher then ambient due to engine proximity and heat soak. One thing that we do to help keep correction factors more accurate is to keep our weather station close to the car's engine compartment. During a long multi Hr tuning session, we often see a 5% increase in the correction factor due to the outside and in-shop temps climbing plus other atmosphere changes. When you're monitoring slight HP/TQ changes based off of tuning changes, it would be impossible to provide a good tune not using corr factors.
A vehicles measured IATs usually run slightly higher then ambient due to engine proximity and heat soak. One thing that we do to help keep correction factors more accurate is to keep our weather station close to the car's engine compartment. During a long multi Hr tuning session, we often see a 5% increase in the correction factor due to the outside and in-shop temps climbing plus other atmosphere changes. When you're monitoring slight HP/TQ changes based off of tuning changes, it would be impossible to provide a good tune not using corr factors.
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From: England
Originally Posted by Phil99vette
The reason I as is, we recently had a car dynoed locally that dynoed @ at a shop who is known for big dyno numbers. The car dynoed close to 500rwhp and 440rwtq when the package was built less than a couple of months ago. When the car goes on the rollers here, it lays down a less than exciting 458/401. The owner was pissed but IMO they are strong numbers. Either the car lost 40/40, which the owner says it runs the same as before or the dyno correction factors can be manipulated.
I was reading an article the other day where the same car was dyno'd with the same mods/setup on the same dyno just under different atmospheric conditions (i.e. on different days).
In STD form there was a 20rwhp difference. Once corrected to SAE there was less than 0.5rwhp (yes you did read it correctly) variance between the runs.
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Verdad Gallardo I've seen many high hp cars on this forum show some strange correction factors when they dyno...like barometric pressure of 28.70 or 29.20 when it was actually close to 30.0...or high ambient temperatures inputed on a cool day.
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2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
