|
|
|
|
| Author |
|
|
Registered
|
5th Gear Question
I'm in the middle of rebuilding a 915/63 transmission.
I started thinking "should I change the 5th gear"? It currently has the 28:23 gear set. The 915/61 and 62 use a 28:22 gear set which is a little taller. I like my current 5th gear but sometimes it seems like I'm in a high rpm for the speed I'm doing. However, it has decent pull...so I guess it's a trade off. I've never driven the 28:22 5th gear. Can anyone tell me what the difference is.
__________________
Matt. 83 911SC 85.5 944 NA - Sold Last edited by arbita1; 03-30-2009 at 04:17 AM.. |
||
03-29-2009, 04:31 PM
|
|
|
Registered
|
I saw this and thought this was going to be about Vicky Butler Henderson......
Sorry, too much time in offtopic. Also sorry, I cannot offer any information. Good luck.
__________________
tk 08 911 C2S - Sold 13 Audi A4 14 Jeep SRT 500HP |
||
|
03-29-2009, 05:29 PM
|
|
|
Registered
Join Date: Oct 2000
Location: Centennial, CO, USA
Posts: 1,405
|
That 28:22 gear is very valuable so hold on to it. It is the desirable SM gear that came on '81-83 Euro SCs and not readily available here in the States. It is the 915:62 gearbox for R.O.W. gearboxes, 915:63 were the USA and Japan gearboxes with 28.23 SN fifth gear. So valuable is the SM gear that just recently I helped arrange for 3 SM gear sets to sent over from the UK from a Pelican (MBEngineering) for some club racers. PCA club racers need this SM gear to be legal in the very competitive E Stock class when they run as Euro SCs. So if you do sell yours here on Pelican, be aware there are some Pcar used parts vendors who will attempt to low ball you for your gear. Your SM gearset is worth at least $400. Oh it is rare to ever use 5th gear in PCA racing but you gots to be legal. HTH and YMMV.
__________________
Bill '72 911T-2.4S MFI Vintage Racer(heart out), '80 911SC Weissach,'95.5 S6 Avant Wunderwagen & 2005 997 C2S new ride. Last edited by zotman72; 03-29-2009 at 07:06 PM.. |
||
|
03-29-2009, 07:02 PM
|
|
|
Moderator
|
Here is a 915/61
 and here a 915/62  and a 915/63  The /61 & /63 use the shorter 28:23 The /62 uses the taller 28:22
__________________
Bill Verburg '76 Carrera 3.6RS(nee C3/hotrod), '95 993RS/CS(clone) | Pelican Home |Rennlist Wheels |Rennlist Brakes | |
||
|
03-30-2009, 04:06 AM
|
|
|
Registered
|
I guess I'm keeping my stock 5th gear. I didn't know the euro taller 5th was so hard to come by.
The shorter 5th gear is probably more usable for busy highway driving anyway. When I had my 85 1/2 944, it had a taller 5th gear. I never really liked it because driving at highway speeds (55mph - 65mph) you had to be in 4th gear otherwise the RPM's were too low and you had no pull at all. Plus the car had no power. When the transmission broke, I replaced it with one from an 88 944 (which had a shorter 5th gear) and I liked it much better for highway driving. I guess if you have highways that you can cruise at 80mph the taller gear is nice.
__________________
Matt. 83 911SC 85.5 944 NA - Sold |
||
|
03-30-2009, 04:34 AM
|
|
|
Registered
Join Date: Oct 2000
Location: Centennial, CO, USA
Posts: 1,405
|
Bill Verburg, you are amazing! I was going to mention that the SM gear was a taller gear but did not have the means validate it (aside from the ratio numbers) but you sir masterly did so with splendid charts and graphics. Well done.
__________________
Bill '72 911T-2.4S MFI Vintage Racer(heart out), '80 911SC Weissach,'95.5 S6 Avant Wunderwagen & 2005 997 C2S new ride. |
||
|
03-30-2009, 05:04 AM
|
|
|
Registered
Join Date: May 2008
Posts: 2,948
|
To run the 28:22 all you need is KERS (+ 80 hp) to push the wind out of the way!
__________________
Keep the Shiny Side UP! Pete Z. |
||
|
03-30-2009, 07:55 AM
|
|
1983 Porsche 911SC
1976 Porsche Carrera 3.0
1995 Porsche 993 Carrera Coupe
