Doug Malone

Anyone know what the gear ratios are in an RS trans and can these gears be applied to the G64/20 gearbox? When I upgrade to an RS clutch and flywheel this will be the perfect time to redo the trans.

Thx,

Doug

D & M Racing

Steve Weiner-Rennsport Systems

Hi Doug:

Here are 2 gearstacks used in the 3.8 Carrera RS:

13/41 3.154
20/40 2.000
23/35 1.522
33/41 1.242
41/42 1.024
39/32 .8210

13/41 3.154
20/40 2.000
23/35 1.522
29/36 1.241
32/33 1.031
35/29 .8290

These were both used in these cars; one is the regular stack and one is the Clubsport stack.

You may use either one in your car but due to cost considerations, I would not change 1st gear. We normally change 2nd through 6th to something better suited for acceleration, not top speed.

Martin S.

Adding some arcane and obscure information to the good stuff previously posted by the Honorable and most esteemed Steve Weiner, and I mean this in all sincerity, check out the following quote out of the Porsche 993 Manual,

”Apart from a few differences, the transmission of the Carrera RS has a similar design to Carrera transmissions G50/20/21; the repair procedures are also similar.

The major differences are as follows:

Different gear ratios (duh!)

2nd gear wheel splined to drive shaft,

Steel/molybdenum synchronizer ring (type G50/32 only)

Limited-slip differential as standard equipment (locking values 40% under acceleration, 60% under deceleration,.

Harder gearbox bearing”

A supplemental approach is to change the ring and pinion gear providing for a higher numerical ratio. ANDIAL sells one (I am certain Steve Weiner sell one as well) for the G50 transmission that provides a 14% reduction, and I believe it is about $1,400 for the set. Install this with the RS gear set, and you'll be going through the gears like a banshee.

This information is provided as a supplemment to Steve Weiner's post. Clearly I have too much time on my hands today.

Doug Malone

Thanks guys. As an alternative, I wonder if it would be more cost effective to just purchase a used G64/21 versus moding my existing G64/20 (has 32K and is very smooth)? However, those RS ratios look awfully enticing and I assume there would be a noticable difference between the RS box and the G64/21.

Doug

Viken

Doug,

You should check here:

Robins Gearbox And Flywheel FAQ

FWIW, the /31 RS 1st gear is a bit too tall for the somewhat torque-less standard 993 engine. I've had the /21 gears since May and find them just about perfect.

os993

My 1995 993 coupe is approaching 90k miles, and here's what I'm thinking of doing:

1. RS LWF with Rennsport Chip (to address stalling). Got the green light from many reliable sources that this will be an acceptable combo for daily driving.

2. Re-gear my G50/20 or purchase used G50/21 tranny?? Decided to re-gear. A bit more $, but more appealing. Will use Paul Guard Gears and steel synchros. Ratio I'm considering is slightly more aggressive than /21 (euro):

1st: Same 3.818
2nd: 2.250 (/21 @ 2.150, /20 @ 2.048)
3rd: 1.650 (/21 @ 1.560, /20 @ 1.407)
4th: 1.286 (/21 @ 1.242, /20 @ 1.118)
5th: 1.040 (/21 @ 1.024, /20 @ 0.928)
6th: 0.820 (/21 @ 0.820, /20 @ 0.775)

While engine is out, will do 30k service, replace spark plug wires, belts, might check intake valves, also considering RS tranny and engine mounts (opinions???)

I'll update when (or if??)I do this. Any feedback on gear choice, or any personal recommendations in re-gearing greatly appreciated and valued.

Cheers!

Doug Malone

Oleg, Are your gear ratios designed for a specific track or did you use some other metric to arrive at these numbers?

Thx,

Doug

DJ

My 3rd, 4th and 5th are nearly the same as yours:
1st: 3.818 (same as stock)
2nd: 2.048 (same as stock)
3rd: 1.600
4th: 1.286
5th: 1.063
6th: 0.928 (same as stock 5th gear)

My gears are also from Paul.

os993

Hi DJ,
So, how do you like the gearing? Would you recommend anythinng?

Also, what's the story with "gear noise"? What does it sound like? Is it an issue?

Hi Doug,
I've been working with various combinations to see what gearing fits my daily driving, as well as tracks. For Thunderhill, the gearing I've chosen would definitely help in Turn 11, Turn 14 & 15.

DJ

I love it. It's not a lot faster than before, except on uphill sections, but it is a lot more fun to drive. What would I recommend? Steel synchros. Mmmm. Smooth shifting.

The gear whine sounded really cool to me, but it almost completely went away after a while. I miss it.