928 Racer with 6-Speed Manual Transmission
05-03-2009, 01:46 AM
#61
Race Car
I remember back when I owned a 968 6-speed that the ratios were very close, especially 4th, 5th and 6th. It was so close that it was kinda weird that the revs dropped so little.
Dan
'91 928GT S/C
475hp/460lb.ft
Dan
'91 928GT S/C
475hp/460lb.ft
05-03-2009, 01:45 PM
#62
Rennlist Member
That long gear shift lever in the race car pictured on this thread looks to be a seqential with that long lever. But if its not, it must have some special linkage to allow for the gear shift pattern to not force the driver to shift with 3ft long throws. 
mk
mk
05-03-2009, 01:54 PM
#63
Rennlist Member
Wow, your right. take a look:
968 gears:
1st = 3.1782, 2nd = 2.000, 3rd = 1.435, 4th = 1.111, 5th = 0.912, 6th = 0.778,
1st to 2nd. very tall 63% rpm drop
2nd to 3rd taller than 928 70% rpm drop
3rd to 4th a slightly shorter 77% rpm drop
4th to 5h a very short 82% rpm drop
5th to 6th a very short , cup car like, 85% rpm drop
This would be an ideal gear box for us! (if it could fit and be strong enough!)
mk
968 gears:
1st = 3.1782, 2nd = 2.000, 3rd = 1.435, 4th = 1.111, 5th = 0.912, 6th = 0.778,
1st to 2nd. very tall 63% rpm drop
2nd to 3rd taller than 928 70% rpm drop
3rd to 4th a slightly shorter 77% rpm drop
4th to 5h a very short 82% rpm drop
5th to 6th a very short , cup car like, 85% rpm drop
This would be an ideal gear box for us! (if it could fit and be strong enough!)
mk
05-03-2009, 03:00 PM
#64
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I would guess that the rod we see is the fulcrum. It's very high so the front/back throw should be short. I think the only concern would be how far sideways you have to move it.
05-03-2009, 03:07 PM
#66
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You can see part of the modsin their pics. There is a box atthefront end of the tunnel. There is enough room to move 3cm back without major mods. You could probably do ~6cm with a sledge hammer, but 12cm requires some major reconstruction.
05-03-2009, 04:19 PM
#67
Race Director
Very interesting....so I wonder how much stronger the turbo RS is vs the stock 968 6 speed....since its pretty easy to find a donor 6 speed from a 968....
05-03-2009, 05:01 PM
#68
Race Director
Okay I did some research....it appears that the G44/00 968 6 speed is the same for all models...at least PET doesn't show a different transmission for the turbos?
The ratios are quite close to what I run now with the 2.64 euro box....using my 6200 redline and 335/30 -18 tires the differences look like this:
928 968
1st 48.2 43.7
2nd 72.2 69.5
3rd 101.2 97.2
4th 133.9 125.1
5th 181.3 152.3
6th --- 178.8
So you get slightly lower ratios across the board and gain a gear between 4th and 5th...but you don't spend much time on track above 130mph anyway???
The ratios are quite close to what I run now with the 2.64 euro box....using my 6200 redline and 335/30 -18 tires the differences look like this:
928 968
1st 48.2 43.7
2nd 72.2 69.5
3rd 101.2 97.2
4th 133.9 125.1
5th 181.3 152.3
6th --- 178.8
So you get slightly lower ratios across the board and gain a gear between 4th and 5th...but you don't spend much time on track above 130mph anyway???
05-03-2009, 10:14 PM
#69
Addict
Rennlist Member
Rennlist Member
Normal PET doesn't know anything about 968 Turbo S or 968 Turbo RS as they both were special models made by Motorsport department.
05-03-2009, 10:42 PM
#70
Nordschleife Master
agreed Erkka, and the turbo RS most likely had completely different ratios.
As to the 951 boxes being stronger, I wouldnt be so sure of that. We are moving heavier cars, and have more torque down low which causes more stain.
And the pivot is from the base of that lever for shifting. with how far up that linkage is you would probably have about 3/4" -1/2" from gear to gear.
As to the 951 boxes being stronger, I wouldnt be so sure of that. We are moving heavier cars, and have more torque down low which causes more stain.
And the pivot is from the base of that lever for shifting. with how far up that linkage is you would probably have about 3/4" -1/2" from gear to gear.
05-03-2009, 10:49 PM
#71
Rennlist Member
If you notice, the gears are close to the 928 (2.64) right up until 100mph, then its more cup car like vs our standard 72% rpm drop like most all production cars of the day up to the late 90s. that close ratio gear box after 97mph, is pretty similar to a cup car close ratio spread. Its still only 3 useable gears, as what I have as well with a 2.2. Lets face it, we drive at the track from 45-50mph all the way to about 125-135mph for the majority of most race tracks. (4 usable for the 968 when going to 135mph) Its too bad they didnt shorten them up in 2-3rd as well.
mk
mk
Okay I did some research....it appears that the G44/00 968 6 speed is the same for all models...at least PET doesn't show a different transmission for the turbos?
The ratios are quite close to what I run now with the 2.64 euro box....using my 6200 redline and 335/30 -18 tires the differences look like this:
928 968
1st 48.2 43.7
2nd 72.2 69.5
3rd 101.2 97.2
4th 133.9 125.1
5th 181.3 152.3
6th --- 178.8
So you get slightly lower ratios across the board and gain a gear between 4th and 5th...but you don't spend much time on track above 130mph anyway???
The ratios are quite close to what I run now with the 2.64 euro box....using my 6200 redline and 335/30 -18 tires the differences look like this:
928 968
1st 48.2 43.7
2nd 72.2 69.5
3rd 101.2 97.2
4th 133.9 125.1
5th 181.3 152.3
6th --- 178.8
So you get slightly lower ratios across the board and gain a gear between 4th and 5th...but you don't spend much time on track above 130mph anyway???
05-03-2009, 10:54 PM
#72
Addict
Rennlist Member
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Even normal 968 6sp box is totally different than any 951 box. Both 968 and 951 boxes are based on Audi gearbox designs but totally different gearboxes.
05-03-2009, 11:07 PM
#73
Nordschleife Master
Erkka,
The G31 (931 ROW & 79/80 US) boxes are very strong boxes, but the syncros are horrid.
I had a good one and put it into a 924 NA that I had years ago, it shifted perfectly still and had a factory LSD fitted. Too bad I no longer have that box!
The G31 (931 ROW & 79/80 US) boxes are very strong boxes, but the syncros are horrid.
I had a good one and put it into a 924 NA that I had years ago, it shifted perfectly still and had a factory LSD fitted. Too bad I no longer have that box!
