Regearing a G50/20 - Questions
Thread Starter
Drifting
Joined: Nov 2003
Posts: 2,817
Likes: 2
From: Alberta, Canada
Regearing a G50/20 - Questions
After a little research I still have some questions. How can you tell if your G50/20 has the loose 2nd gear without taking it apart? My car is a '95 and the gearbox numbers are "50 20 001 2959". VIN is 322562.
A G50/31 is starting to look like the best box after you consider selling the old box except I've heard that you can't get one now. I came to the conclusion that the 1/2 and 2/3 shift needed to be closer which means changing 3 gears plus std overhaul parts plus an LSD (while your in there) and your up to $8-9k minimum. If my 1st and 2nd gears are integral then the fixing the 1/2 shift is really not practical economically. Here are the ratios I was thinking of based on changing the 2 gear set out (from another Rennlister's build) :
3.818 stock /20
2.375 new
1.789 new
1.407 stock/20 - was 3rd
1.118 stock /20
0.821 new. I could stick with the stock 0.775. Its tall but acceptable.
Any thoughts are appreciated. This is mostly for street road use hence the need for a tall 6th gear.
A G50/31 is starting to look like the best box after you consider selling the old box except I've heard that you can't get one now. I came to the conclusion that the 1/2 and 2/3 shift needed to be closer which means changing 3 gears plus std overhaul parts plus an LSD (while your in there) and your up to $8-9k minimum. If my 1st and 2nd gears are integral then the fixing the 1/2 shift is really not practical economically. Here are the ratios I was thinking of based on changing the 2 gear set out (from another Rennlister's build) :
3.818 stock /20
2.375 new
1.789 new
1.407 stock/20 - was 3rd
1.118 stock /20
0.821 new. I could stick with the stock 0.775. Its tall but acceptable.
Any thoughts are appreciated. This is mostly for street road use hence the need for a tall 6th gear.
Drifting
Joined: Mar 2009
Posts: 2,389
Likes: 6
From: Seattle
As of a couple weeks ago per Sunset a /21 w/ LSD is about $12K. A /31, of which there was only (1) in all of the system, is $14.8K. Both quotes include a core charge, which is mandatory unless a like gearbox is available for exchange.
Here's a Bill V. post as to your first question.
Here's a Bill V. post as to your first question.
All of the /20 & /21 can have 3-6 changed easily enough, 1 & sometimes 2 are integral w/ the main shaft, the changeover trans #s are
G50.20 - 02693
G50.20 - 02174 (M220)
G50.21 - 05072
G50.21 - 03094 (M220)
before only 1 is fixed after 1 & 2 are fixed, to change them a new mainshaft is required(last price I saw Was ~$2000, I'me sure it's much more now)
The Motorsports boxes, /30 -/33 have loose gears in all positions 1-6
Many choose to leave the main shaft alone and change 3-6 and that works but isn'e really an optimal way to do it.
G50.20 - 02693
G50.20 - 02174 (M220)
G50.21 - 05072
G50.21 - 03094 (M220)
before only 1 is fixed after 1 & 2 are fixed, to change them a new mainshaft is required(last price I saw Was ~$2000, I'me sure it's much more now)
The Motorsports boxes, /30 -/33 have loose gears in all positions 1-6
Many choose to leave the main shaft alone and change 3-6 and that works but isn'e really an optimal way to do it.
Thread Starter
Drifting
Joined: Nov 2003
Posts: 2,817
Likes: 2
From: Alberta, Canada
Thanks for the reply. I had found Bills post but am not sure I understand what he trying to say . What is the M220? Is he saying any G50/20's above 2693 are changed to the integral second gear? At those steep prices regearing makes alot more sense (unfortunately
).
).
Drifting
Joined: Mar 2009
Posts: 2,389
Likes: 6
From: Seattle
M220 is the code for LSD. I read it as the G50/20's w/ LSD above 2174 have the integral second. G50/20's w/o LSD above 2693 have the integral second.
Rennlist Member
Joined: May 2001
Posts: 3,052
Likes: 8
You don't need most of the stuff in a /31 for a street car. You really just want three gears -- 3rd, 4th, and 5th. Frankly, you don't even need a limited slip.
I built a quasi-RS gearbox by rebuilding my LSD with Guard friction discs and adding the RS 3, 4, and 5th gears. I prefer the stock 6th for quiet/fuel efficient highway cruising. Since you want to build a street box, you don't need steel syncros and upgraded shift forks and all that stuff.
Just install the three gears and you'll have -- again, for street use -- almost all of what an RS box provides.
I built a quasi-RS gearbox by rebuilding my LSD with Guard friction discs and adding the RS 3, 4, and 5th gears. I prefer the stock 6th for quiet/fuel efficient highway cruising. Since you want to build a street box, you don't need steel syncros and upgraded shift forks and all that stuff.
Just install the three gears and you'll have -- again, for street use -- almost all of what an RS box provides.
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Thread Starter
Drifting
Joined: Nov 2003
Posts: 2,817
Likes: 2
From: Alberta, Canada
You don't need most of the stuff in a /31 for a street car. You really just want three gears -- 3rd, 4th, and 5th. Frankly, you don't even need a limited slip.
I built a quasi-RS gearbox by rebuilding my LSD with Guard friction discs and adding the RS 3, 4, and 5th gears. I prefer the stock 6th for quiet/fuel efficient highway cruising. Since you want to build a street box, you don't need steel syncros and upgraded shift forks and all that stuff.
Just install the three gears and you'll have -- again, for street use -- almost all of what an RS box provides.
I built a quasi-RS gearbox by rebuilding my LSD with Guard friction discs and adding the RS 3, 4, and 5th gears. I prefer the stock 6th for quiet/fuel efficient highway cruising. Since you want to build a street box, you don't need steel syncros and upgraded shift forks and all that stuff.
Just install the three gears and you'll have -- again, for street use -- almost all of what an RS box provides.
Last edited by matt777; Oct 3, 2010 at 10:06 PM.
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Rennlist Member
Joined: May 2001
Posts: 3,052
Likes: 8
How often do you use 1st gear for winding the car out to redline, where the 1-2nd spacing comes into play? I probably do that a couple of times a year...99 percent of the time 1st is used to get rolling, and then you use 2nd, 3rd, etc, to actually drive the car.
Do whatever you like, but it sounds to me like you're intent on a course of action that will require you to spend more money on first gear, which is barely ever used anyway, than on the entire rest of the gearbox, pricing yourself out of the whole project.
Do whatever you like, but it sounds to me like you're intent on a course of action that will require you to spend more money on first gear, which is barely ever used anyway, than on the entire rest of the gearbox, pricing yourself out of the whole project.
Thread Starter
Drifting
Joined: Nov 2003
Posts: 2,817
Likes: 2
From: Alberta, Canada
How often do you use 1st gear for winding the car out to redline, where the 1-2nd spacing comes into play? I probably do that a couple of times a year...99 percent of the time 1st is used to get rolling, and then you use 2nd, 3rd, etc, to actually drive the car.
Do whatever you like, but it sounds to me like you're intent on a course of action that will require you to spend more money on first gear, which is barely ever used anyway, than on the entire rest of the gearbox, pricing yourself out of the whole project.
Do whatever you like, but it sounds to me like you're intent on a course of action that will require you to spend more money on first gear, which is barely ever used anyway, than on the entire rest of the gearbox, pricing yourself out of the whole project.
Details to follow if it isn't gone already.
Rennlist Member
Joined: Jan 2005
Posts: 599
Likes: 17
From: MA
I don't mind the stock 1st to 2nd, the real fun is 2nd -> 5th and any good stretch of open road.
Here is a plot of the stock US box followed by what I had built. The only thing I changed in the new box from the gearing in the diagram was replacing the 6th with the original gear which I like better on the highway and IMHO you really shouldn't need that final 5th->6th shift to be close unless your are on one fast long race track.
Here is a plot of the stock US box followed by what I had built. The only thing I changed in the new box from the gearing in the diagram was replacing the 6th with the original gear which I like better on the highway and IMHO you really shouldn't need that final 5th->6th shift to be close unless your are on one fast long race track.
Banned
Joined: Feb 2004
Posts: 2,361
Likes: 9
From: SF Bay Area
Stock 1st to 2nd bugged the crap out of me. Also, 6th gear is way too tall in my opinion.
The g50/31 is $$$$, but it fixes all that and makes the car sooooo much more enjoyable. It was really worth the expense for me.
Cheers,
Joe
The g50/31 is $$$$, but it fixes all that and makes the car sooooo much more enjoyable. It was really worth the expense for me.
Cheers,
Joe
Drifting
Joined: Mar 2006
Posts: 2,432
Likes: 36
From: Hannover
Get 1st gear mainshaft assembly with splined 2nd, regear 2nd to 5th, move stock 5 to 6. I have this combo and IT ROCKS. However, you are looking at about 4-5 kUSD in parts only and if you add the LWF and RS clutch ... I am glad the previous owner made this investment.
