Rear gear changes affect Dyno results?

[pgriffith]

Will my rear gear changes affect my dyno results? I had the car dyno'd with old gears 3.23's and I now have 3.73's and want to get them dyno'd after I install my new cam. Are the gears going to affect my dyno #'s?

[Boehlke]

I've also been wondering this....

[camaro_zach]

higher gear = lower numbers. With my 4.10's i will get crappy results compared to 3.23's, however im 10x faster ;) hehe.

[pgriffith]

I guess dyno's dont mean **** then. I wanted to get a before and after dyno of my new cam but I guess now I wont. Oh well, what do #'s matter anyway. ITs all about track times in my book.

[NBMA4V6]

why would that matter. you would be dynoing the gains. unless you change gears along with the cam after the intial dyno than the gains would show up from the cam.

understand?

[pgriffith]

I had my dyno done with my 3.23's and my crower regrind cam. I now have 3.73's and I am in the process of installing my new compcam.

[V6Blur]

from 3.23's to 3.73's you may loss around 5-10 hp at most.

[HAZ-Matt]

I think someone is going to have to explain why you lose horsepower when you install different gears. Are they heavier? Harder to turn?

[Mike Mayron]

<blockquote>quote:</font><hr>Originally posted by camaro_zach:
higher gear = lower numbers. With my 4.10's i will get crappy results compared to 3.23's, however im 10x faster ;) hehe.<hr></blockquote>

Ummm... How about no.

Dynos work by taking a know mass (the drum) and calculating the time your car takes to accelerates it over time. That'll give you torque x rpm data which can then be calculated to hp x rpm.

Gears don't matter nor do the gear the tranny is in as long as the torque converter is locked if using an A4. Yes the smaller (physicaly) the gear the more power it'll eat but you'd be hard pressed to notice it on a dyno. Changing the rear end fluid probably makes a bigger power loss/gain then smaller gears.

Not tring to be mean or pick on you either zach. I'm just tired of seeing people state things as fact when they don't really understand what's actually happining.

I think the dynojet web site had a nice little explaination on how they work.

[hou-tex-six]

<blockquote>quote:</font><hr>Originally posted by Mike Mayron:


Ummm... How about no.

Dynos work by taking a know mass (the drum) and calculating the time your car takes to accelerates it over time. That'll give you torque x rpm data which can then be calculated to hp x rpm.

Gears don't matter nor do the gear the tranny is in as long as the torque converter is locked if using an A4. Yes the smaller (physicaly) the gear the more power it'll eat but you'd be hard pressed to notice it on a dyno. Changing the rear end fluid probably makes a bigger power loss/gain then smaller gears.

Not tring to be mean or pick on you either zach. I'm just tired of seeing people state things as fact when they don't really understand what's actually happining.

I think the dynojet web site had a nice little explaination on how they work.<hr></blockquote>

Im gonna have to go with this, or else there would have to be some kind of correction factor.

Cp

[NBMA4V6]

it is well known fact that higher the gears the lower the dyno results. it may go against the "theory" but in every case i can almost gaurentee that results will be lower with more gear you have
[img]smile.gif[/img]

[camaro_zach]

<blockquote>quote:</font><hr>Originally posted by Mike Mayron:


Ummm... How about no.

Dynos work by taking a know mass (the drum) and calculating the time your car takes to accelerates it over time. That'll give you torque x rpm data which can then be calculated to hp x rpm.

Gears don't matter nor do the gear the tranny is in as long as the torque converter is locked if using an A4. Yes the smaller (physicaly) the gear the more power it'll eat but you'd be hard pressed to notice it on a dyno. Changing the rear end fluid probably makes a bigger power loss/gain then smaller gears.

Not tring to be mean or pick on you either zach. I'm just tired of seeing people state things as fact when they don't really understand what's actually happining.

I think the dynojet web site had a nice little explaination on how they work.<hr></blockquote>


no offense taken. i have been told by NUMEROUS people, including magnus, that higher gear = lower number on the dyno. mabye there is a correction for this, im not aware, but i have ALWAYS been told higher gears make for lower numbers. If you found it on their site, please link us all so that we can all be informed.

[HAZ-Matt]

http://www.ls1info.com/print.php?sid=167