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cobra2112
10-25-2005, 07:06 PM
What kind of HP/TRQ difference could you get from one dyno to another? I have had 450hp/468trq at one dyno. Installed a catback went to another dyno (closer to home) and ran 426hp/452trq. Just wondering if there could be that much of a difference between dyno's.:doubt:

InfamousSVT
10-25-2005, 08:21 PM
Depends:

Mustang Dyno usually gives out lower numbers, but are better to use for tuning. Since the car is on a load.

Dyno Jet usually puts out higher numbers due to the fact that you're putting the car up on a big "roller" and just spinning it.

Most people are more familiar with the dyno jet numbers.

*edit*
Also, depending on when the last time the dyno was calibrated might have something to do with the numbers, but every dyno won't be the exact same.

blk04cobra1
10-26-2005, 07:44 AM
the real test is at the track...Infamous did a good job of telling you the differences, so it sounds like the first dyno was on a dynojet and the second was possibly on a Mustang dyno...or you can run someone you previously ran and see if the outcome is different :thumbsup:

kilroy
10-26-2005, 09:32 AM
What kind of HP/TRQ difference could you get from one dyno to another? I have had 450hp/468trq at one dyno. Installed a catback went to another dyno (closer to home) and ran 426hp/452trq. Just wondering if there could be that much of a difference between dyno's.:doubt:SAE #s are supposed to be comparable between like dynos.

Find one & stick with it.

Like you, I used a dynojet a couple hours away - I'll go back at least once more to get an apples-to-apples comparison after my latest upgrade but the ATS MD dyno is where I'll be going from here on out.

Eddy current dynomometers measure differently & their real world numbers are often 10-15% lower. Dynojet recently came out with their own eddy-current dyno, too. That tells ya something ratch there :thumbsup:.

You also want to find out if the dyno is regularly maintained/calibrated.

Pro-Dyno
10-28-2005, 12:27 AM
You also need to keep in mind all the other conditions temp, humidity, altitude, barometric pressure and like every one else said Dyno type. As far as dynos are concerned they all have to have drag to give a reading. Some use weight like a Dyno jet this type of Dyno calculates the speed you turn the 3,500 pound drum verses the the speed your vehicle accelerates threw the rpm band. A mustang type Dyno uses an electric brake that adjusts pressure to the rollers to simulate vehicle weight. These Dyno’s have to be programmed with the weight of the vehicle that is running so the load breaker can properly adjust its self. So if the weight is input inaccurately the # will vary. Then it takes a calculation of rpm acceleration verses wheel torque or pressure against the rollers to maintain a specific lode to calculate rwtq and rwhp

Hope this helps

:thumbsup: