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Gear ratio affect dyno #'s??

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Old 12-28-2003, 02:40 PM
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Default Gear ratio affect dyno #'s??

Would changing the gear ratio, that is rearend gear ratio, have an affect on dyno numbers?? For instance, I have 3.73's now and dynoed 339hp/347tq. When I get my 12 bolt with 4.11's, how would it affect my numbers, considering everything is the same with the car except the rear and gears??
Old 12-30-2003, 03:48 PM
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Yes, the 12 bolt is going to affect dyno #'s. Reason being, the 12 bolt is much more rotating mass than the 10 bolt, therefor it requires more power to run. This ONLY affects dyno measurements. The HP is still there, just not reading to the rear wheel due to the extra load. Gear ratio's also have an effect....The steeper you go in gears, the more it will affect the dyno...IE: A 3:73 will dyno higher than a 4:10...

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Old 01-04-2004, 12:31 PM
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I was about to post this question also. I really would like to know why your dyno readings would be lower with a higher gear ratio? Especially considering that you pick up both et and mph when going up in gear.
Old 01-08-2004, 11:45 PM
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We went after this topic pretty seriously a while back. You can find the post here:

https://ls1tech.com/forums/showthrea...driveline+loss

This may help you out, or tell you more than you ever really wanted to know.

Enjoy!




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