NA87FC

I'm thinking about using my s5 TII tranny when I rebuild my engine. Someone told me something about TII trannys not wanting to shift at high rpm's? I thought that sounded kind of ridiculous. Is this true?

peejay

The people I have seen dragracing them had problems shifting over 8000rpm.

If you have a nice N/A, you will want to be shifting over 8000rpm.

It could have been their gearboxes, too. I've had smoothcase transmissions that hated shifting and others that shift like butter at 9000rpm.

NA87FC

I don't think I do. It gets stuck in reverse sometimes. The car has 147k on it.

ultimatejay

iTrader: (1)

Check out my vid in my sig. I am shifting at 10k with a stock s5 TII trans. and although I am pretty much granny shifting, I have no problems with the gears going in- no grinding yet. If you are going to power shift, then I could see some problems. Some people will modify the gears inside the box to straight cut gears and modify the shift forks so that you just have to tap the clutch and mash the gears in. This is what I will probably run next as I can't afford a 4000.00 clutchless trans. I heard the s5's shift better than the s4's.

NA87FC

I planned on using the S5.

Mazdanowski

Where can you source straight cut gears to put in a TII or a set for a NA tranny for that matter?

Black91n/a

http://www.rotorsportsracing.com/per...drivetrain.htm

peejay

The cut of the gear has nothing to do with shifting. It's the type of sliders that it has that is important - synchronizers vs. dog rings.

Good synchros work, but the TII transmission's design dates back to a transmission with a horrible synchro design. I haven't had one apart yet, but generally, the heavier the geartrain, the more difficult the synchronizer life is.

This is why T56s shift like ****. Lots of mass for the synchros to deal with, and tiny stubby shifters too.

Oh yeah - shifting is much easier if you make the shifter about 6" longer. Ram past those pesky synchros

j9fd3s

iTrader: (3)

yep! the gears are constant mesh, ie they are always mated together. its the slider/synchro that mates it to the shafts

to find a trans thats NOT constant mesh, you have to dust off the wayback machine and go back to the 1950's

peejay

AFAIK all domestic 3-speeds had non constant mesh 1st gear.

VW 020 transmissions (rod shift, transverse FWD) have a sliding Reverse gear. It's easy to f-up by grabbing Reverse instead of 1st when downshifting. Reverse goes CLANK CLANK CLANK after you do that

Come to think of it a lot of FWD transmissions have a sliding Reverse.

Jeff20B

iTrader: (13)

Yep, I think the Fiat X-1/9 is like that. You can grab reverse while driving forward. It turns on the reverse lights and doesn't make too horrible of a noise. A great way to flash your brights at the car behind you.

crpdragracing

Call Liberty Transmissions (Yes the Big guys) and they i'll take care of your problem. If you want to see prove of this, check this video:
http://www.youtube.com/watch?v=O5v57ml3RdE