I searched but must have missed it somewhere. What would the rpm in 5th gear be at 65 miles per hour if I swap to 3.73s in an 03 V6.

I am curious and have been thinking of it for a while but I kind of like the gas mileage and don't want to **** it up.

Also if it does mess with mileage what does it go down to on the HWY.

 

Ok, finally found the calculator in another post that tells you the rpm for the gear run.

My question now for those of you that have 3.73 with a stock manual trans in a 6 is -

With the stock 3.27s @ 65 mph - it says I am turning about 1891 rpms -which sounds about right.

If I switched and went to a 3.73s @ 65 - it says I would be turning 2157 rpms.

So my question is how bad would it hurt my gas mileage?

 

i have 3.73's, i dont have a standard but if ur constantly flooring it then you will diffenetly see a big drop in ur gas mileage.

If you take it easy you will only see about 1-2 mpg drop

 

ive got the 3.73's in a 5spd v6, i actually got a lil better gas mileage because the gears helped the running i did around town. i didn't notice a big difference with the highway mileage. i'd do it over again. btw, i think on average i'm getting right around 20 mpg. i seem to go everywhere on 3/4 throttle...

 

Are you guessing or are you calculating? I keep careful track of mine and with stock gears and somewhere between 1/2 and 3/4 throttle, I only get 17.5 mpg in the city.

 

Yeah, I'm in the same boat as you. 17 for a V6? I mean, seriously? I hate it.

 

With mine I getting better than that but as far as how much exactly I don't know. I know I get around 28-30 on the hwy but if I combo my mileage I get about 20-22 average.

 

i usually get 19.5+ to 20.sumthing. and i think ur city driving is a little different then my city driving as i live in a rather rural city.

 

but yea, compared to ohhh any other v6 out there, ours do get crappy gas mileage...




...oh and i now have 1,000 posts!!!! wahoooo!!!!!

 

My old fox body (5.0) with a 5 speed and 3.73's ran 2100 rpm's @ 60 according to the stock tach. It's the same gear ratios as yours. I always got 22.something to 23 mpg. That's with weak rings and running the **** out of the thing in combined "rural city" and highway driving.
3.8 mpg is pretty sad. But, my wife's V6 firebird (automatic) in almost completely city driving averages 12 something if it makes you feel better. It can pull off a 22 or 23 on the highway. Still not as good as my five liter now.

 

Yeah, it's probably a little worse living in Orlando. If I didn't have to stop as much I'd probably be around 19 or so.