All your gears will be shorter . Your max speed will be less for all gears

 

so instead of your top speed being 155 over all its going to be like 140????

right now this is about what my gears are

1st gear - 0-35
2nd gear 36-60
3rd gear 60-100
4th 100-145
5th 146-155

^these are just estimated they are a few MPH off but not much...
now with the gears if everyone of them is shorter that means that my top speed it going to be less right??

 

Yes - top speed is less - I top out at about 142 now - I think - I haven't taken it all the way to redline in 5th. I won't make it past 90 without a shift to 4th, but I get there much faster than before.

Gears are usually meant for 1/4 mile and road racing. Bottom end will seemingly be better as you get to the power band much faster.

Rick

 

great thread

 

If you want to research it more . [ Sentry ] on this site and My350 has done alot of data figuring and posted all the info about the 3.5 and 3.9 gearing . You will get GOOD INFO from him

 

Thanks!

 

Thanks rick! Since im not FI will it make a difference in my 1/4 times you think? I usually trap about 99MPH and i switch into 4th at i believe 98MPH so i do not get much pull at all as i cross the line...if i switch into 4th at about 90mph will my trap speed be higher than 98-100MPH?? Will my 1/4 mile inprove?

 

Nice, thanks. We are going to have a talk when I am ready for FI. I may need some advice from you.

 

newb!!!!

 

Ok, boosted justin im a noob because im consered about putting a part i dont know about on my car? When did you join this forum again? When i joined in april im pretty sure you were not a member here.....(i had a different name box87)

Maybe instead of being a tool bag and since im such a "noob" you could help explain....?

 

Technically yes - your 1/4 times should improve. Typically going from 3.35 (AT) gears to 3.92's can get you in upwards of .5 sec, sometimes more in the 1/4.

Rick

 

Are the shift points at about the same for the g35 6MTs as an 5AT with 3.92 gears? im just conserned about shifting into 4th before the 1/4 mile line as 4th at 100mph does not start pulling until you are at about 110 so i gain those 10 MPH fairly slow compared to going 110 to 120MPH....im just consered because i do not know alot about gearing ratios i have never had them explained to me so i do not know how they work...

 

Quite simply - you will get into power band much faster...and the MPH you have power, will change, it will be lower, so your previous 110 MPH issue will be about 20% less - roughly. The gear change to the 3.92's from the 3.35's is about 20% shorter...so rounding it out means everything will happen about 20% faster - though not proportional to 1/4 mile times ;-)

 

so with these im assuming i will shift into 4th gear at 90MPH. I would i still be trapping speeds 98-100 mph or would i be trapping higher speeds since 4th gear would last until about 125 or so??? I just want to know if i would be trapping higher or lower speeds since 4th gear is obviously alot slower than 3rd gear for instance..

haha sorry for all the questions

 

You'll likely trap slightly higher speed, but it's the ET that will change. You'll get there faster, but not necessarily in MPH as a ratio.

Rick