michel j

If only 1st gear could be changed to reduce the drop between 1 - 2. Wish someone could figure this out. The rest, I am ok with.

ToSi

California Motorsports advertises a replacement 'weld-on' 1st gear set.

http://www.californiamotorsports.net...06%20speed.htm

Asked in a previous thread but didn't get any replies - has anyone tried this?

993RS

Look at the charts:
http://www.californiamotorsports.net...20%20stock.pdf
http://www.californiamotorsports.net...21%20stock.pdf

Shortening 2nd gear reduces the drop. If you shorten 1st gear (leaving the rest as is) you increase the drop.

If you lengthen 1st gear, you reduce the drop, but reduce your acceleration.

gridlock61

Hmmm, interesting. I'd be interested in anyone's experience with this as well.

gridlock61

Well, I suppose you can make 1st a bit taller, then change the final drive so that 1st would end up where it was. This would also reduce the RPM drop between all the other gears. Has anyone tried this? Unless I'm missing something, it seems like an interesting idea, since only one gear is changed, yet the spacing between all gears is reduced.

michel j

Yes, but 1st gear acceleration out of the hole is not important to me. The BIG drop in going to second is the problem for many. Most 915 gearboxes and the 5 speed G50s have a most reasonable 1st gear ratio of 3.5 to 1. The G50/20 and G50/21's 1st gear ratio is 3.8XX to 1. Why did they do they this? I don't know, but, it is what it is.

I have called CMS and asked them about the 1st gear replacement 3.5 to 1 on my g50/20. Apparently, they machine the old gear off and weld an "Albin" gear on it in its place. I asked about gear noise and they told me that ANY after market gear will be noisier than stock. That is the nature of after market gears.

What is so magical about the Porsche gear sets that allows them to be so quiet? I do not understand why these gears cannot be machined/ contoured or whatever it takes to make them to have low NVH. If enough people wanted to have this done to their transmission, maybe someone would figure this out.

The rest of the G50/20's gears are not optimum, but, are not bad in my opinion. I find 2nd and 3rd very good in many instances. I like 6th for cruising on the freeway, its not optimum, but, better than having 5th moved to 6th in my opinion.

gridlock61

These guys sell two alternate ring and pinion sets for the G50 for $2,700 http://www.retro-sport.com/products/...nion-sets.html.
This is a stock gearing chart: http://www.californiamotorsports.net...20%20stock.pdf.
This is a chart with the 4.0 final drive: http://www.californiamotorsports.net...5020%20400.pdf.
Still seams like reasonable highway cruising in 6th, although Retro Sport sells a final drive in between stock and the 4.0 (3.44).

Bill Verburg

Here's another look at some options, as i said earlier the /21 is going to be the most satisfying w/o changing 1. the /30 is great but for street use could use a bit taller 6, the /31 or /32 solve all the problems, for track use more than just gearing needs to be changed, there is more of the good stuff in the /3x than /2x, /30 >/32>/31>/2x

il pirata

Porsche figured it out. Just have to pay the piper if you want to regear and keep it OEM quite.

gridlock61

Bill,

Are you saying that these options can be purchased outright, or is just a reference for swapping gears in a stock G50-20? What's your thought in making 1st taller, and reducing the final drive (higher numerically) as mentioned in the other post?

os993

I did 2nd thru 6th and used the euro 6th. Absolutely necessary. 6th US gear sucks. I would hate to have had my 5th as 6th. Also as my car is a '95, it was easy to do 2nd, which was also a great upgrade.

Bill Verburg

I don't know about current options, but in the past brand new rebuilt trans could be purchased from Porsche on an exchange basis(usually like for like but sometimes just outright), several guys here bought /31 and /32 that way. Several others have purchased /21 and /30 used from Race shops or European salvage.

The individual gears are also available from Porsche and from aftermarket sources to gear however you desire. Porsche gears are quieter because of the finish process but I would not be concerned about that given the ambient nois in these cars.

I just present what it looks like, this is not an inexpensive proposition and it's easy to mess things up. As I said before it's best to look at the interactions of the engine and transmission installed in the car, but you need rear wheel torque #s to really do that right, so if that isn't an option then you assume that your engines s a healthy typical 993 3.6 and see how it would perform w/ a specified gear set.

A typical re-gear includes moving 5 to 6, I think that this is a bit too low but you can experiment on your own by driving around in 5

You can also look at the transmission alone, but again it sure helps to know what you are looking at and why somethings are good and others not so much.

Of course feed back from others that have done this is valuable too but humans being the cantankerous sorts that they are opinions will vary.

My thoughts are any of the /3x transmissions would make anyone happy and they should therefore by at least a target to be emulated. But that's just My opinion.

993RS

With Steve's gearing, 1st remains unchanged, 2nd is 10% shorter, all the rest are 20% shorter. No holes anywhere. Not cheap though...

michel j

I would love to go that route but that is an expensive proposition. I have read to budget over $1k/gear, X 5, plus labor, plus a couple more $k while you are in there. That is $10 grand. Paying the piper - using Porsche gear sets, would be much higher than that.

Changing the r and P has been discussed a few times. This would not change spacing at all and would make 1st gearing seem even lower, which is not a fix at all. Its too low already. And then there is the gear hunting issue with the even ratio of gear teeth.

How many of you would consider having 1st re-geared to 3.3 or similar with tranny freshening bits for $5K? Even the 96 to 98 MY could take advantage of this one. I know I would.

Bill Verburg

Here's a CWP change to 4.0, 1 & 2 are ridiculous 6is like moving 5 to 6 in a stock box