Torque
#16
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You are correct it is a better box!!! Has many "good" features.. Gear ratio's and oil pump/oil cooler. Better limited slip.. 2 wheel drive!!
But you would have to modify the box or adapt for the cable shift.. I would also install the better mainshaft..
We should have a thread.. The ultimate gearbox..
Edit, it should read.. "build the Ultimate Gearbox" Jean your gearbox doesn't count (smile)
But you would have to modify the box or adapt for the cable shift.. I would also install the better mainshaft..
We should have a thread.. The ultimate gearbox..
Edit, it should read.. "build the Ultimate Gearbox" Jean your gearbox doesn't count (smile)
#17
So many things have come up here-- I tried not to keep waffling earlier to keep relevent-- but will elaborate.I have made these comments much earlier to Jean pre his sequential .I set out to build the ultimate G50/52 with ratios etc at great expense with the idea of saving some gear changes at crucial points while racing.Theory was there are a number of times where the physical track position can be changed by saving a gear change so passing becomes possible.All good in theory.Interesting part of all this is and previous post is this-- same track ,different year-- gearbox problems saw change from the G50/52 after missing qualifying while changing to 6 speed from my n/a RS CS which was geared for only 260 kmh at 7100 ( we had to raise turbo rev limiter to minimise time on it) and being forced to the back of the grid to start the race --- went from last to a close 3rd and set a new lap record in the process. Took nearly a second off my previous best ever lap and learnt some valuable lessons.Despite being busier than a one armed paper hanger and driving nearly all the time one-handed,unsuitable ratios , far more gear changes it was/has proven faster to have more gears.Subsequently ,I have gone to 6 spd with the right ratios-- essentially longer 1 & 2 and not too tall a 6th gives the best results .The obvious ultimate solution is new generation sequential that can save the shifting time and maximise the forward momentum.
#18
Drifting
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Red9, Is your car a 996TT or 993?
who did your tranny and where do you live?
I too am interested in taller first two gears and lower 6th (or maybe keep 6th the same)
MK
who did your tranny and where do you live?
I too am interested in taller first two gears and lower 6th (or maybe keep 6th the same)
MK
#19
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Originally Posted by Jean
]
I might be mistaken, but it does seem to me that Porsche engineers have kept taller gearing for turbos in mind across all their models. This might be due to many factors, but certainly performance was one of them. RUF has mastered this art in all his cars, and one can see substantially taller gears (except 6th) on his CTR2 Sport for instance.
I might be mistaken, but it does seem to me that Porsche engineers have kept taller gearing for turbos in mind across all their models. This might be due to many factors, but certainly performance was one of them. RUF has mastered this art in all his cars, and one can see substantially taller gears (except 6th) on his CTR2 Sport for instance.
I secret information from a good source that some Ruf Ctr2's were running 4:00 ring and pinions for the race circuits.
Jimmy the fugitive
993tt 3.8 Andial twin plug
A bunch of AMG's
#20
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Red9
I need to clarify that what I was saying earlier applies to straightline acceleration. On tracks, gearing changes are certainly necessary to have themcustomized for the specific track. If a certain track has the longest straight where you can reach 160mph, you would want your rev limiter to hit right there, not before, not much after. The options are unlimited and one of the key successes of winning a race.
For straight line acceleration, taller gears seem to benefit more your times.
I will trade my G64/51 6 speed gearbox with a 5 speed stock G50/52 anyday, then do some tests and show the results.
Jim, (the felon, the ex-felon? ) yes that is what Beddor runs most likely On race circuits however, you know better than most of us, there are many variables and the stock CTR2 Sport ratios are probably way too tall for a racing environment, especially when fitted with 345/30 in the rear.
Here is a comparison between a RUF CTR2 Sport and the 993TT. The RUF comes with 325/30 stock and 3.44 R&P. The 993TT obviously does not reach the rev limiter in 6th for top speed, this is shown for illustrative purposes. I would not take the speeds as exact, many facotrs would influence them, but comparing like for like, the results are quite astonishing! The RUF Sport revs up to 7K RPMs I presume?
I need to clarify that what I was saying earlier applies to straightline acceleration. On tracks, gearing changes are certainly necessary to have themcustomized for the specific track. If a certain track has the longest straight where you can reach 160mph, you would want your rev limiter to hit right there, not before, not much after. The options are unlimited and one of the key successes of winning a race.
For straight line acceleration, taller gears seem to benefit more your times.
I will trade my G64/51 6 speed gearbox with a 5 speed stock G50/52 anyday, then do some tests and show the results.
Jim, (the felon, the ex-felon? ) yes that is what Beddor runs most likely On race circuits however, you know better than most of us, there are many variables and the stock CTR2 Sport ratios are probably way too tall for a racing environment, especially when fitted with 345/30 in the rear.
Here is a comparison between a RUF CTR2 Sport and the 993TT. The RUF comes with 325/30 stock and 3.44 R&P. The 993TT obviously does not reach the rev limiter in 6th for top speed, this is shown for illustrative purposes. I would not take the speeds as exact, many facotrs would influence them, but comparing like for like, the results are quite astonishing! The RUF Sport revs up to 7K RPMs I presume?
Last edited by Jean; 10-17-2006 at 09:14 AM.
#22
Nordschleife Master
Excuse my ignorance (my experience ends with the old 901 gearbox), but couldm't you take a stock 993TT, change just the ring & pinion for something about 20% taller than stock, and pretty nearly acheive the Ruf CTR ratios? Isn't this a cost effective solution (if you want to achieve that taller gearing)?
#23
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Jean,
You are correct, Mr. B likes to run near redline in top gear on whatever track he runs at,
so he has been known to change the rear end ratio. Like you said it is way too high stock
for most track use.
MK
You are correct, Mr. B likes to run near redline in top gear on whatever track he runs at,
so he has been known to change the rear end ratio. Like you said it is way too high stock
for most track use.
MK
#24
CA-- you could change ring & pinion to 8:32 or 4 to 1 that would lower ratios to more usable top speed.The down side is that you shorten the already to low 1st and 2nd gears . I am considering exactly that for 996 GT2 at the moment. It is easily reversible ,quick,cheaper solution than changing ratios. The Cup and R race gearboxes have the longer 1st and 2nd and generally the 8:32 . The downside is that the taller 9:31 will not wear as quickly as the 8:32. All of that presumes you are not V-maxing with a target of 320KMH plus.
#25
Nordschleife Master
Red9,
I'm trying to acheive just the opposite of what you are suggesting... I want taller gears throughout... like the Ruf CTR gearbox, but I wonder if you can acheive that with a taller ring and pinion. Maybe I should not use the word "taller"... longer? I want higher top speed in each gear by simply swapping the R&P. Is that possible? Is there such a R&P made that will fit the stock 993TT transaxle? Thnaks
I'm trying to acheive just the opposite of what you are suggesting... I want taller gears throughout... like the Ruf CTR gearbox, but I wonder if you can acheive that with a taller ring and pinion. Maybe I should not use the word "taller"... longer? I want higher top speed in each gear by simply swapping the R&P. Is that possible? Is there such a R&P made that will fit the stock 993TT transaxle? Thnaks
#26
Nordschleife Master
I may have answered my own question... it appears that there is no taller ring and pinion available for the 993TT gearbox... 9:31 is as tall as you can go. Too bad... a 10:29 would have been ****.
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Steve
I was searching to see if I can find any, and I didn't. Although it might have been a good idea.
When you shorten gears you obviously reduce the RPM drops between gear changes, with an R&P change alone you don't. Therefore the opposite is also true, an R&P that would give you taller ratios, would leave the rev drops the same, not make them wider.
Don't know if it makes sense, but since they are not available off the shelf anyway, it does not look like an option.
I was searching to see if I can find any, and I didn't. Although it might have been a good idea.
When you shorten gears you obviously reduce the RPM drops between gear changes, with an R&P change alone you don't. Therefore the opposite is also true, an R&P that would give you taller ratios, would leave the rev drops the same, not make them wider.
Don't know if it makes sense, but since they are not available off the shelf anyway, it does not look like an option.
#29
Nordschleife Master
Red9, Jean,
I find that 1st and 2nd gear are way too short for practical use, and a more "relaxed" 6th gear would be nice for cruising. The Ruf CTR box looks like great ratios, and I was hoping for a cheaper way to achieve similar performance. Looks like no deal anyway. Thanks for the ideas,
I find that 1st and 2nd gear are way too short for practical use, and a more "relaxed" 6th gear would be nice for cruising. The Ruf CTR box looks like great ratios, and I was hoping for a cheaper way to achieve similar performance. Looks like no deal anyway. Thanks for the ideas,