different dyno , different readings
- Thread starter angus
- Start date
I did 5 different dynos, my low was 318 and high was 396. Same car, same ambient temps, same gas, same tune. I don't read much into dyno numbers.
Man that is a huge variation. Do your "butt dyno" measurements vary that much too? :tongue:
No man, my butt dyno reads 375.62 every single time. It's highly accurate so long as I am driving with no pants.
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- 5 February 2007
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mustang dynos will read 13% less than any other dyno
5 different clocks, 5 different times...but they can all pretty accurately tell time passage/change.
5 different weight scales, 5 different weights...but each will show ~ the same CHANGE in weight.
In other words, use the same dyno (at about the same conditions) to compare upgrades/modifications...
Even with the same type of dyno, numbers can be dramatically different. My car was dyno-tuned on a dynapack in Phoenix after I had my SOS supercharger installed, and it showed 385 RWHP. I recently had my car dyno'd locally, also on a Dynapack, because another local NSX owner had just installed the same SC and only got ~350 RWHP, and his car and mine were virtually identical in terms of engine mods. So he wanted to compare to mine. My car dyno'd 320 RWHP, with similar environmental conditions. Only difference would be fuel.
same "type" watch, same type scale...same type (unreliable comparison) results.
SAME dyno, SAME car, SAME conditions...comparable results.
My car read the following on 3 different dynos with identical temps and no changes to the car. (I believe this was one or 2 days back to back)
396 WHP on 1 dyno
402 WHP on another dyno
438 WHP on the last one
One year later in another state it made 397 WHP
Last November it made 420 RWHP on Driving Ambition's dyno
396 WHP on 1 dyno
402 WHP on another dyno
438 WHP on the last one
One year later in another state it made 397 WHP
Last November it made 420 RWHP on Driving Ambition's dyno
- Joined
- 10 November 2003
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- 1,066
I was within 20HP from two dyno's. one problem I had on my last dyno was spinning the wheels in a 3rd gear pull.
Why were you doing a pull in 3rd gear?
cause thats the gear you are supposed to do it in.....it has the closest 1-1 ratio.....
what have you done yours in?
LOL.....just went through the same thing here Wil...
I asked about the Mustang dyno on another forum and found out it is nick-named the "Heart-breaker" or "Humbler".. and the difference in those two numbers is EXACTLY the % difference they said it would be!
Stacy
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i have a dyno dynamics and current config with X factor correction im 10% lower then my buddies dynojet
i put down i think 350 on my 4 banger, went over to his dyno next day and picked up 40 horses. Everything is the same with car warmed up. the TQ was spot on tho.
people who know dynos dont put much weight on dyno numbers since its like apples & oranges. Also shops will fudging the correction factor just to put out better numbers.
better numbers = happy customers after all, dropping 13000$ on a comptech SC + install, people want to see the real BIG numbers of 80+HP.... even if realistically is 40-50hp at the wheels. :biggrin: also shops are under great pressure to fudge numbers even if it has nothing to do with their tuning.
its easy to pick up or loss 40-60hp when you get into the higher hp depending on which dyno and more if you fudge the correction factor.
i personally always ask for HP then what dyno was used.
take it all with a grain of salt.
i put down i think 350 on my 4 banger, went over to his dyno next day and picked up 40 horses. Everything is the same with car warmed up. the TQ was spot on tho.
people who know dynos dont put much weight on dyno numbers since its like apples & oranges. Also shops will fudging the correction factor just to put out better numbers.
better numbers = happy customers after all, dropping 13000$ on a comptech SC + install, people want to see the real BIG numbers of 80+HP.... even if realistically is 40-50hp at the wheels. :biggrin: also shops are under great pressure to fudge numbers even if it has nothing to do with their tuning.its easy to pick up or loss 40-60hp when you get into the higher hp depending on which dyno and more if you fudge the correction factor.
i personally always ask for HP then what dyno was used.
take it all with a grain of salt.
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what kind of fuel difference was it? did you use the same tune? :biggrin:
also just to point out, your in Vancouver which is sea level + 0 and Phoenix is 1,086 FT (334M) above sea level ( its like driving your car to the top of grouse mountain and dynoing it there). For each 1000Feet you go up, you lose 3% ( on a NA car but still losses to be had with FI) or in your cause you should have GAINED something if not 3% given the numbers where not fudged to your satisfaction. Also keep in mind IAT temps. Im willing to bet that air temp in phoenix is much hotter then the nice cool in the summer, mild in the winter climate of Vancouver. You should be making more power at sea level then in phoenix + lower iat temps = more power on top of that..... chew on that tid bit. :smile: Not sure who is in phoenix but they are fudging your numbers to sell sc/tc kits.
should have had your SC installed locally like the other guy and saved on transport cost and gotten a better "real" number and probably paid a TON of money less on install labor.
shops love selling big numbers cause it brings people in the door. Out right lie to your face.... most likely, however, it brought you in the door right? Then the customers go home and run it on the street or a unfudged dyno and they either get beat down or let down. By then its too late. $ already in the bank :biggrin::biggrin:
its just the business. want a 320RWHP stock 3.0L 5 speed? i can print you out a dyno chart of one
I understand some of you might not like what im saying about dynos. if you dont like what im saying about dynos and the business of "selling hp", its the facts. take it or leave it.
everyone wants to be a horse power hero.
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4th gear is actually closer. (on a 5 speed)
5th gear on a 6 speed.
Unless you've done some gear ratio mods...
http://www.nsxprime.com/FAQ/Technical/gearratios.htm
Who's dyno did you run on? I am looking at 17% between RG (mustang AWD) and Resnick (Dynojet 2WD).
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Or with a boulder of salt. According to a Clayton Hydrokinetic dyno my car puts out 408 rwhp. In the exact same configuration and state of tune, a Bosch FLA-203 dyno came up with 270 rwhp. Damn!
I checked around who has an accurate dyno and I found one testing facility in the area that actually calibrates their dyno every few weeks. Unfortunately, they charge a couple hundred Euros per run. Every other dyno facility I called calibrates their dyno only every couple of years or not at all. That could go a long way towards explaining why dyno numbers are all over the place.
I went to Resnick's but he wasn't comfortable with strapping the car down.
So I thanked him for being honest and moved on!
I found a Mustang dyno here in Ridge at Haney automotive and performance.
Stacy
:biggrin:
a dyno is more of a tool then a "certificate" of power
what a dyno should be used for is dyno the car before a modification, make changes, then run the car again. you'll know if hp was gained for lost and go from there on to the next mod.
dyno charts give you a reasonable estimate but the only way to tell if you faster then the next guy is to run it at the track.
i once raced this guy who said his car read 520HP on a dynojet.... my car at the time pulled off 340hp on my dyno.
we where neck and neck.... i didn't even both tell him my dyno numbers since it was break his heart. :tongue:
when i tune, i use my dyno. when i want big numbers, i go to my buddies dynojet :smile:
Hi Bud, just curious what were your final results? RWHP
330 rwhp on the mustang dyno which would be around the 380-390 rwhp on a Dynojet.
This was with the supercharger making 3.8 PSI of boost.I have since ordered two smaller pulleys.....one for 5.5 PSI and another for 6+ PSI....so we will see.
Stacy
So wouldn't a graphical presentation of an acceleration measured in g's be more accurate?
This would solve many problems with the dyno's as we know them.
It would also present much more the driving experience rather then dumb torque and horsepower.
This would solve many problems with the dyno's as we know them.
It would also present much more the driving experience rather then dumb torque and horsepower.
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