ibeeskeef

I was using the gear calculator on the sticky and it shows that 4:10's and 4:30's have the same RPM's in 5th gear at all the mph's I tried (75, 80, 85). Is this true? And if so, why don't people go with 4:30's every time instead of 4:10's since the RPM's are the same in 5th and the 4:30's pull harder?

Tim37

245-45-17 tires

at 60mph with 4.10 gear rpm 2127.3
at 60mph with 4.30 gear rpm 2262.5

not much but there is a diffence.

ibeeskeef

i have 275/40/17's. Is that making the RPM's the same or what?

01yellowgt

no clue whats going on there then. 315/35/17 & 275/40/17 & 245/45/17 are all three the same diameter, so that shouldnt be an issue.

Cobra_Dan had 4.30's on his manual gt. No clue of anyone else.

jdaniel

There isnt much difference at all in the two. I had 4.10's in my car for the longest and was ready to go to 4.30's before I got rearended.

Blue70

With 4.30's
Your tire's diameter is 25.681 inches
At 70 MPH in 5th gear, your motor is turning at 2,442.6 RPM

With 4.10's
Your tire's diameter is 25.681 inches
At 70 MPH in 5th gear, your motor is turning at 2,329.0 RPM

I'm not sure if this is the program you used, but it's the one I use

Click HERE for calculator

blackbetty01

How was someone able to catch up and rear end that thing!! J/K, I have been meaning to ask you about that picture, did you get it fixed or part it out and total it?

jlauth

i was just on that calc how fast do you think that my car would be able to go cuz i was gonna see how that top speed would differ with 4.10 to my 3.73s. that was one of the two reasons that i went with the 3.73 the other was cuz of collegeand the dist from home.