got 2.73's now, dont get that good of gas mileage as it is, does anyone have ACTUAL examples of swapping the gears and how it affected their gas milage.....or what is you guy's RPM at 65, mine is 1800 right now, what im considering is 3.73's anyone have exp/stories????

 

Have a friend with 3.73s in. They are ok and he gets decent gasmilage (around 250 miles to a tank + or - 30miles)
We are going back to the 3.42s though b/c of the 383 thats in his car now. Too much wheel spin!
At 70 the car is around 2500 rpms..

 

Can anyone give me a for sure RPM # for crusing at 65, for example, my 2.73's run at 1800@65, im curious what the others run for an A4, is an A4 better or worse about gears afftecting gas mpg, does anyone have any numbers, i would consider 3.23, 3.42, or 3.73, or maybe even 4.11's , post sum up if you guys have time
thanks

 

For calculating gear changes/speeds/rpms, try this:
F-Body Gear Calculator

I went from 3.42 to 3.73, and I have M6. I didn't notice any changes in fuel milage, but then again I drive mostly in city traffic.
Hope that helps!

 

Wow, that calculator is one bad mother. That is exact as you can get with that thing. Thanks for the link.

 

If your complaining about gas mileage now, with your 2.73's...your REALLY gonna be hurtin then when you go higher.

I went from 2.73's to 3.73's and the change was HUGE!!! I had then, all the mod's listed in my sig and the car would take off from a stop like mad, and from a roll, seemed to move like a rocket! Best mod I did to date, without a doubt!

HOWEVER, 65mph is @ ~2500rpms and 80 is just under 3krpms. With my 2.73's, I was getting between 320-370 miles per tank, now, I'm luck to break 250 miles per tank.

Sooo, weigh the cost to benefit factor and go from there. IF you dont drive consistently fast on the highway and are looking for a 'pick me up' mod...do it! If you have any doubts though, go with a lower gear then.

Also, do you plan to get Heads/Cam...cause if you do, then consider keeping them for the time being.

 

man that sux, i was thinking more around 2k like the other guys in this forum, i definetely plan on getting a cam, should i get the cam before the gears????? or how does that affect it...?

 

I have 3.23 in my car. I constantly drive 80MPH on the turnpike and I am at 2500rpms. If you have 2.73 and are thinking about and upgrade, I would recommend getting a set of 3.42. I have a few friends that went with 3.73 and then changed down to a 3.42 or 3.23 and like those better. They said it was a little more liveable (gas mileage wise) for everyday driving. I think the 3.42 would give you the umph you are looking for but still give you decent gas mileage too.

My 2 cents.
Claude

 

RPM stand for Revolutions Per Minute. RPMs would then stand for Revolutions Per Minutes! So my question to you is, "How many minutes did your engine take to turn 2500 revolutions!" You dont say MPHs do you? Sorry not flamming, not too much anyways, but it is a huge petpeev of mine. Saying "RPMs" is almost as bad as saying "Nazz"!

This education brougt to you by Clemson Engineering, haha.

 

ditto, im thinking about stepping down to the 3.42's my gas mileage sucks, but i like the quick torque responce, so its kinda comes down to a trade off as to what you want