5point7 said:
Ratios in the 300C are 2.82 and in the SRT8 they are 3.06.
The Biggest bang for your buck driving around town is gears - by far. The car will get out of the hole much quicker and into the RPM's. Won't do much for 1/4 times, but it is a lot funner to drive.
As far as mileage and rpm's on the freeway - my experience says it won't change much.
The ring and pinion is indeed a 2.82 on the 300C. And by past experience, yes this platform definitely needs a better gear ratio. Getting 4000 lbs out of the gate with this motor is no easy task. The 5.7 litre just does not have enough "bottom end" torque.
On the SRT8 - the
tranny gears are the same but they use a 3.06 ring and pinion and the gas mileage is just fine!! I cruise at 75-80 in my SRT8 and easily get 22 mpg on a regular basis.
This car (300C) could easily use 3.23's or even 3.42's and the highway milaege would still be in the range of 20 mpg's. By going to a 3.23 gear the approx drop in the 1/4 mile would be .4 or .5 tenths and easily 3-4 mph trap speed faster. -- That would be a BIG NOTICE in the every day driving of the vehicle!! Now the
BIG ?-- Do they make such a Ring and Pinion for this platform???