Gearing is too long! Why no gear mods? My #1 dislike.
07-30-2019, 11:17 PM
#16
I've a 1990 Honda 750cc motorcycle that clears 80mph in 1st gear, now that is annoying. At least motorcycles are cheap and easy to change gearing with a new front or rear sprocket. I wish my 08 Porsche had a taller 6th gear for the highway.
07-31-2019, 03:16 AM
#17
Nordschleife Master
Why do you want shorter gears? The 6 cogs already are close-ratioed. If you switch to shorter gears, you will need far more gears to cover it all. 6 gears is more than enough.
Whatever speed/torque advantage you would gain from shorter gears would be lost in shifting times. And... low shorter gears could break traction - a no-no in 911s.
Whatever speed/torque advantage you would gain from shorter gears would be lost in shifting times. And... low shorter gears could break traction - a no-no in 911s.
07-31-2019, 04:43 AM
#18
Nordschleife Master
Great info. Thx. On a different note, my only complaint about the gearing which isn't really about the gearing is the relentless search for a higher gear in normal/auto mode (and in sport/auto mode) on the PDK which is why I never use either one. Frankly, I don't don't understand why they offer the normal mode to begin with. In 6th gear at 30 mph or something like that in auto mode borders on lugging imo. It's been so long since I used it I forgot the shift points but it's somewhere along that line. To me, even sport mode is on the lame side so for PDK, sport plus manual is the only mode I'm ever in with few exceptions.
07-31-2019, 09:12 AM
#19
RL Community Team
Rennlist Member
Rennlist Member
Thread Starter
Why do you want shorter gears? The 6 cogs already are close-ratioed. If you switch to shorter gears, you will need far more gears to cover it all. 6 gears is more than enough.
Whatever speed/torque advantage you would gain from shorter gears would be lost in shifting times. And... low shorter gears could break traction - a no-no in 911s.
Whatever speed/torque advantage you would gain from shorter gears would be lost in shifting times. And... low shorter gears could break traction - a no-no in 911s.
Peace
Bruce in Philly
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driggity (07-31-2019)
07-31-2019, 01:38 PM
#20
Nordschleife Master
My post is about the manual transmission not PDK. Further, the closeness is not my concern, it is 2nd and 3rd gear are too long - you are going to fast at redline. The fun of manual transmissions is to drive the car in its highest horse power band, 5K to redline... the fun zone. With the current ratios in the manual transmission, you have to blasting around local roads at very high speeds... slowing for a curve, normally you would downshift from 3rd to 2nd and be in the fun zone as you take the curve... but you will always be in 2nd anyway.... no shifting.... no fun.
Peace
Bruce in Philly
Peace
Bruce in Philly
The 6-speed and PDK cog ratios in the 997.2 are very similar. If you make second gear shorter... what do you do to 3rd, 4th, 5th, 6th? Do you end up with gaps or do you pay the price to limit Vmax? And of course you would be using the engine in an inefficient manner.
07-31-2019, 01:41 PM
#21
Nordschleife Master
Great info. Thx. On a different note, my only complaint about the gearing which isn't really about the gearing is the relentless search for a higher gear in normal/auto mode (and in sport/auto mode) on the PDK which is why I never use either one. Frankly, I don't don't understand why they offer the normal mode to begin with. In 6th gear at 30 mph or something like that in auto mode borders on lugging imo. It's been so long since I used it I forgot the shift points but it's somewhere along that line. To me, even sport mode is on the lame side so for PDK, sport plus manual is the only mode I'm ever in with few exceptions.
Im freeway traffic or city driving one can be in Normal mode in 6th gear at a low speed. The engine does not lug in my experience. however, a sudden throttle stab might it lug. So downshift manually.
07-31-2019, 04:31 PM
#22
Shifting into 1st gear while moving in a manual is not desirable. There are tight hairpin turns in the mountains here. Turns with 10-15mph advised speeds and 30mph speed limits. In the manual at 30mph it puts you at 3200RPM in the corner. 3200RPM corresponds to the point where the cam is fully in the low lift position and about to shift from the low RPM lift to the high RPM lift and the response is a bit awkward at that RPM range. If 2nd redlined at 50mph (I've had a bunch of cars geared with such a ratio), the gearing in this car would put you at 4400RPM coming out of the corner at 30mph. Now the engine is alot more responsive, ferocious even. You could apply the same to a regular street corner. Corner entry/exit at 25-30mph.
Likewise, we have some excellent tunnels in a canyon just a couple miles from my house. The speed limit on that section of highway is 35mph and very heavily patrolled by the State Patrol (road leads to casinos). Blasting through the tunnel with the windows down is one of the most fun things you can do in a PSE car. But at 3500RPM its a bit bland. Redline however, will put you 30mph over the speed limit in 2nd and 65mph over the limit in 3rd. I hear that's kinda frowned upon by the fuzz.
Our point is, bringing the gearing down on 2nd and 3rd would change the engine RPM in a way that would make the power-band more accessible legally on the street without the speed being so high that you're going to have major problems.
Last edited by GoldenGorilla; 07-31-2019 at 04:50 PM.
07-31-2019, 07:03 PM
#23
Nordschleife Master
Compared to what? The 9A1 low end torque is low compared to a Chevy LT1 or a turbo of comparable top end power.
Again, this conversation is not about the PDK but the Manual transmission. The transmission which makes Sport mode permanent (if the driver chooses). The transmission chosen by those who LIKE to change gears. If breaking traction was our concern we'd already be sliding all over the place in 1st, which isn't happening. Changing the gearing does not necessarily require changing all the gearing so long as the drive ratios can be synchronized. Close ratio gearboxes are not the only solution, nor are they always the best solution. I've owned cars with manuals in 3 speed, 4 speed, 5 speed and 6 speed. Trucks/jeeps, Sedans, sports cars, all of them manuals. As such, I've driven a bunch of wide ratio and close ratio gear boxes. Close ratio is fun if the ratios are accessible. To use those ratios in the 997 manual in the engine's powerband you're gonna be traveling way above the speed limit of US highways. Different story on the track, but still we who drive manuals don't dislike shifting even if it is slower than the ultimate robo-shifter. None of us is getting paid for our lap times.
Shifting into 1st gear while moving in a manual is not desirable. There are tight hairpin turns in the mountains here. Turns with 10-15mph advised speeds and 30mph speed limits. In the manual at 30mph it puts you at 3200RPM in the corner. 3200RPM corresponds to the point where the cam is fully in the low lift position and about to shift from the low RPM lift to the high RPM lift and the response is a bit awkward at that RPM range. If 2nd redlined at 50mph (I've had a bunch of cars geared with such a ratio), the gearing in this car would put you at 4400RPM coming out of the corner at 30mph. Now the engine is alot more responsive, ferocious even. You could apply the same to a regular street corner. Corner entry/exit at 25-30mph.
Likewise, we have some excellent tunnels in a canyon just a couple miles from my house. The speed limit on that section of highway is 35mph and very heavily patrolled by the State Patrol (road leads to casinos). Blasting through the tunnel with the windows down is one of the most fun things you can do in a PSE car. But at 3500RPM its a bit bland. Redline however, will put you 30mph over the speed limit in 2nd and 65mph over the limit in 3rd. I hear that's kinda frowned upon by the fuzz.
Our point is, bringing the gearing down on 2nd and 3rd would change the engine RPM in a way that would make the power-band more accessible legally on the street without the speed being so high that you're going to have major problems.
Again, this conversation is not about the PDK but the Manual transmission. The transmission which makes Sport mode permanent (if the driver chooses). The transmission chosen by those who LIKE to change gears. If breaking traction was our concern we'd already be sliding all over the place in 1st, which isn't happening. Changing the gearing does not necessarily require changing all the gearing so long as the drive ratios can be synchronized. Close ratio gearboxes are not the only solution, nor are they always the best solution. I've owned cars with manuals in 3 speed, 4 speed, 5 speed and 6 speed. Trucks/jeeps, Sedans, sports cars, all of them manuals. As such, I've driven a bunch of wide ratio and close ratio gear boxes. Close ratio is fun if the ratios are accessible. To use those ratios in the 997 manual in the engine's powerband you're gonna be traveling way above the speed limit of US highways. Different story on the track, but still we who drive manuals don't dislike shifting even if it is slower than the ultimate robo-shifter. None of us is getting paid for our lap times.
Shifting into 1st gear while moving in a manual is not desirable. There are tight hairpin turns in the mountains here. Turns with 10-15mph advised speeds and 30mph speed limits. In the manual at 30mph it puts you at 3200RPM in the corner. 3200RPM corresponds to the point where the cam is fully in the low lift position and about to shift from the low RPM lift to the high RPM lift and the response is a bit awkward at that RPM range. If 2nd redlined at 50mph (I've had a bunch of cars geared with such a ratio), the gearing in this car would put you at 4400RPM coming out of the corner at 30mph. Now the engine is alot more responsive, ferocious even. You could apply the same to a regular street corner. Corner entry/exit at 25-30mph.
Likewise, we have some excellent tunnels in a canyon just a couple miles from my house. The speed limit on that section of highway is 35mph and very heavily patrolled by the State Patrol (road leads to casinos). Blasting through the tunnel with the windows down is one of the most fun things you can do in a PSE car. But at 3500RPM its a bit bland. Redline however, will put you 30mph over the speed limit in 2nd and 65mph over the limit in 3rd. I hear that's kinda frowned upon by the fuzz.
Our point is, bringing the gearing down on 2nd and 3rd would change the engine RPM in a way that would make the power-band more accessible legally on the street without the speed being so high that you're going to have major problems.
You are entitled to your opinion and the way you want to use the car. Do not like the ratios? Change them, plenty of shops who can do that for you if you cannot do it yourself.
08-01-2019, 10:51 AM
#24
RL Community Team
Rennlist Member
Rennlist Member
Thread Starter
... but still we who drive manuals don't dislike shifting even if it is slower than the ultimate robo-shifter. None of us is getting paid for our lap times.
There are tight hairpin turns in the mountains here. Turns with 10-15mph advised speeds and 30mph speed limits. In the manual at 30mph it puts you at 3200RPM in the corner. 3200RPM corresponds to the point where the cam is fully in the low lift position and about to shift from the low RPM lift to the high RPM lift and the response is a bit awkward at that RPM range. If 2nd redlined at 50mph (I've had a bunch of cars geared with such a ratio), the gearing in this car would put you at 4400RPM coming out of the corner at 30mph. Now the engine is alot more responsive, ferocious even. You could apply the same to a regular street corner. Corner entry/exit at 25-30mph.
Our point is, bringing the gearing down on 2nd and 3rd would change the engine RPM in a way that would make the power-band more accessible legally on the street without the speed being so high that you're going to have major problems.
There are tight hairpin turns in the mountains here. Turns with 10-15mph advised speeds and 30mph speed limits. In the manual at 30mph it puts you at 3200RPM in the corner. 3200RPM corresponds to the point where the cam is fully in the low lift position and about to shift from the low RPM lift to the high RPM lift and the response is a bit awkward at that RPM range. If 2nd redlined at 50mph (I've had a bunch of cars geared with such a ratio), the gearing in this car would put you at 4400RPM coming out of the corner at 30mph. Now the engine is alot more responsive, ferocious even. You could apply the same to a regular street corner. Corner entry/exit at 25-30mph.
Our point is, bringing the gearing down on 2nd and 3rd would change the engine RPM in a way that would make the power-band more accessible legally on the street without the speed being so high that you're going to have major problems.
Peace
Bruce in Philly
01-21-2020, 08:01 PM
#25
Rennlist Member
Gearing
Bruce,
I had a pro driver whip my 997.2 around Sebring. It is EVIDENT that the gearing is a miss. The issue is 2nd and third.
For a track car, Fifth should be sixth, and 2,3,4 and 5 be fixed. This car has the main shaft where it is pressed on, not keyed.
I had a pro driver whip my 997.2 around Sebring. It is EVIDENT that the gearing is a miss. The issue is 2nd and third.
For a track car, Fifth should be sixth, and 2,3,4 and 5 be fixed. This car has the main shaft where it is pressed on, not keyed.
01-30-2020, 04:45 PM
#26
Rennlist Member
I wonder if having a different final drive would effectively make the existing M6 gears feel shorter.... google comes up with this
https://www.kmpdrivetrain.com/produc...ve-7-35-i5-00/
haven't look at it closely enough to see if this is going in the right direction but I thought I bring it up for others to explore the idea.....
https://www.kmpdrivetrain.com/produc...ve-7-35-i5-00/
haven't look at it closely enough to see if this is going in the right direction but I thought I bring it up for others to explore the idea.....
01-30-2020, 08:22 PM
#27
Burning Brakes
As we are in thread resurrection/day dream territory, I don't mind the gear ratios for puttering around, but my top wish for track driving
would be a dog-legged layout, so that I can use second gear more often.....
would be a dog-legged layout, so that I can use second gear more often.....
02-10-2020, 10:56 PM
#28
Rennlist Member
I have been reading that the 997.2 transmission is an Asin unit, built with a main shaft that has the gears pressed on.
Are there any other transmissions that mate to this engine? I am hearing that the 996 gearbox is splined Getrag unit. Any thoughts?
Are there any other transmissions that mate to this engine? I am hearing that the 996 gearbox is splined Getrag unit. Any thoughts?