Jasoon

Hey guys,

I know that several of you with 6ixers have made the swap to 3.73 gears.

I'm wondering, once the gear thrashing and tire burning power is over, and you are cruizing on the highway at 70 mph, what is your engine running RPM wise on the tach?

I'm also curious if the rpm's would be the same, in a swapped out 8.8 versus building up the 7.5?

I realise that stronger gears mean a little less gas milege, but there is a "spot" with my exhaust that it is louder than any other RPM. I'm trying to figure out if I swap gears if I'll be in that spot all the time.

kenny17

I was wondering the same, I might ask for these for christmas but I do alot of highway driving. I think I saw on a review on AM someone said in his 5spd he's at 2500RPMs at 65mph.

157dB

8.8 =S AN 8.8" RING GEAR

7.5 =S A 7.5" RING GEAR

THE RMPS ONLY CHANGE WHEN THE RATIO CHANGES, NOT THE PHYSICAL SIZE...

Fricken caps lock...

You can do the math or use an online calculator...

Just change the ratio variable from 3.31 to 3.73
in the equasion and that will tell you real world
RPMs...

05AV6

I have an auto with 3:73's it will tach about 2600/2800 at 70/75/80 MPH. Not too bad about another 500 rpms higher than the stock gear set.

Sancho805

yup... i see about 2500rpm at 70mph.

laterider

I had worked this up for stock V6 tires when doing my research, but seems a little off from what some are saying here - so I may need to go look at my math!!! LOL .71 is for the automatic ratio in overdrive and there are calcs for 4 different rear ends..

Nuke

PM me with your e-mail and I'll send you 2 spreadsheets I have that'll give you all that info. You also need to input your tire size as this will also affect RPM's.

4.0 $tang

your gonna need to get a tuner, if you dont already have one...i find myself driving in 4th gear on the highway still...it gives me an incentive to pass because i am in the better part of my power band...gets to 70 really quick from 50...

what other mods do you have and are you also if you got with the 7.5 you should really get a t-lok
just my 2 cents

Jasoon

Current mods include Hurst shifter, Magnaflow duals cat back kit, and some unknown cone air filter on my intake.

Future performance mods include gears, a tuner for those gears,
and the WMS intake, (if I can ever find a hood to take advantage of it's design.)