taller 3rd & 2nd

[VW911]

I am in the process of gear selection for my tranny. I want to use a 3.88 r&p and a .821 4th gear.

Has anyone used this final drive combo ( 3.88 r&p/ .821 4th) with taller 2nd and 3rd gears?

I have found that using a stock 1974 3rd gear going into a taller 4th gear drops into a big hole when shifting into 4th.

Purpose:

I want a taller third to bridge the gap, and make it smoother transition. This transmission is suppose to be for highway driving but not sacrifice bottom end. I am currently using a 1641cc dual carb'd motor, but will be going to a 2270cc T4.

[Bruce2]

What size are your rear tires?
I have that a trans with 3.88x.82, and with a 24.5" tall tire I found the gearing a little too tall for my 2 liter. When I had 23" tires it was a little too short.
I didn't find the drop that bad. Perhaps with your 1641 you don't have enough power to pull that taller 4th. With your proposed engine, you will have a lot more bottom end torque, so the gap won't seem that bad.
If you are set at changing 3rd, you could go to a 1.21 or 1.19. I wouldn't change 2nd. That gets real expensive ($5-600).

[VW911]

I do not have my wheels yet. I plan on using 18x8 & 18x10 porsche wheels with stock tire sizes, or maybe the 17x7 & 17x9's with stock sizes.

I know the current motor I have does not have the torque I am looking for throughtout the RPM range. But my T4 will.

Thanks for the advise on the 2nd and 3rd gearing.

[Bruce2]

before you pick your gears, you have to choose your outside tire diameter.

[boygenius]

before you pick your gears, you have to choose your outside tire diameter.


265 / 35 x 18" = 78.5" circumferance with 30% tread remaining on my 18" x 10" turbo twists. :D