3:90 gear in an A4
3:90 gear in an A4 Anyone here have 3:90gear in an A4? Im thinking of swapping gears and thought abuot 3:90 gears.I originally was gonna go 3:73,but some one mentioned I should ask about a 3:90 gear.Right now i have 3:23 and a 3500 stall.Im H/C/I and put down 417rwhp and 407rwt.Not that it matters or anything,but how much Rwhp would it lose if i whent to 3:90 from the 3:23 I have now.Am I just better off going with 3:73 or stay with what i have
thanks
john
thanks
john
I just installed a 3.90 in mine. Drives fine, not a lot of extra RPM's over the 3.23. Not a drastic improvement on the street due to the extra traction loss. I was going to post earlier but seeing as how I havent been to the track I dont have any real hard facts. You are really talking about approx. a 6% difference in RPM, so the difference between a 3.73 and a 3.90 is negligible. If you think the extra RPM's are needed or you might go with a taller tire, you should do it.
Originally Posted by mzoomora
I just installed a 3.90 in mine. Drives fine, not a lot of extra RPM's over the 3.23. Not a drastic improvement on the street due to the extra traction loss. I was going to post earlier but seeing as how I havent been to the track I dont have any real hard facts. You are really talking about approx. a 6% difference in RPM, so the difference between a 3.73 and a 3.90 is negligible. If you think the extra RPM's are needed or you might go with a taller tire, you should do it.
let me know what you think and thanks again
john
with the 3.90 gear you would max out at 129mph in 3rd geara nd going 70mph on the freeway you be at 2500rpms. Now with the 3.73 you would max out at 135mph in 3rd gear and run 2400rpms. This is based on a 6600rpm redline. So if your not going to be trapping over 129mph i say go for the 3.90 especially since there is a 100rpm difference with freeway driving.
