Shorter gears for the 991? Anyone done it!
#16
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Hey guys,
I have a 50th 911 7 spd manual and from day one I thought the gears were too tall. It hits 72 mph in 2nd gear. I also thought about the shorter R&P like Larry suggested, in fact this issue has been raised in the GT forums by those who own the GT4. That car has only 6 gears and 2nd gear goes to 82 mph! So really not a lot of places in the US where you can "legally" use even the 3rd gear on the street.
The request was brought up to Guard Transmission but it was shot down. They have no intention of making a shorter R&P, at least not for any sort of road use. They are willing to sell you a whole new trans with all new gear ratios, but that's for racing only. The reason? too expensive to make and they will never recover the cost for tooling.
I'd LOVE to have a shorter R&P--in fact I think it's the ONLY short coming (
) of the non-GT 911s. Especially with the NA engines the shorter R&P would shift the torque curve and take advantage of the high revs. The Holinger sounds promising, but is that for road use? On the website it says it's for the cup cars. I'd pay big $$$ for it if it's a direct swap (doubtful).
I have a 50th 911 7 spd manual and from day one I thought the gears were too tall. It hits 72 mph in 2nd gear. I also thought about the shorter R&P like Larry suggested, in fact this issue has been raised in the GT forums by those who own the GT4. That car has only 6 gears and 2nd gear goes to 82 mph! So really not a lot of places in the US where you can "legally" use even the 3rd gear on the street.
The request was brought up to Guard Transmission but it was shot down. They have no intention of making a shorter R&P, at least not for any sort of road use. They are willing to sell you a whole new trans with all new gear ratios, but that's for racing only. The reason? too expensive to make and they will never recover the cost for tooling.
I'd LOVE to have a shorter R&P--in fact I think it's the ONLY short coming (
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#18
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I think you have to recall that the PDK based box is a very complex transmission (manual or otherwise) not designed to have ratios replaced...
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
#19
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I think you have to recall that the PDK based box is a very complex transmission (manual or otherwise) not designed to have ratios replaced...
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
#20
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I think you have to recall that the PDK based box is a very complex transmission (manual or otherwise) not designed to have ratios replaced...
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
#21
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ZF makes the PDK and Aisin (outsourced) makes the manual. The transmissions are very, very similar. The PDK has shorter ratios believe it or not.
If Guard Transmission can provide shorter geared race transmissions that would be one way to go. I'm sure it can be made more street friendly. I doubt the PDK can be replaced - too many complicated software tweaks and / or drivetrain inefficiencies to address.
Larry is right, I only know of two other G50 transmissions that have shorter ratios aside from mine. I've placed a shorter Getrag OEM 2nd gear in my 997.1 GT3.
If Guard Transmission can provide shorter geared race transmissions that would be one way to go. I'm sure it can be made more street friendly. I doubt the PDK can be replaced - too many complicated software tweaks and / or drivetrain inefficiencies to address.
Larry is right, I only know of two other G50 transmissions that have shorter ratios aside from mine. I've placed a shorter Getrag OEM 2nd gear in my 997.1 GT3.
#22
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It's unfortunate that Porsche doesn't offer shorter gear ratios as an option in North America, which is their biggest market.
The long gear ratios make sense when driving on the autobahn, but not when driving a sports car on the backroads and highways of North America.
Technologically, they would have to do a lot more R & D to produce and computer model shorter ratios on a PDK car, but it wouldn't be that hard for Porsche to produce shorter gear ratios for manual 911s and it's the manual drivers who most need shorter gear ratios to start with.
They could call it sport plus manual transmission and charge an extra $3000 from the factory, and people would buy it.
The long gear ratios make sense when driving on the autobahn, but not when driving a sports car on the backroads and highways of North America.
Technologically, they would have to do a lot more R & D to produce and computer model shorter ratios on a PDK car, but it wouldn't be that hard for Porsche to produce shorter gear ratios for manual 911s and it's the manual drivers who most need shorter gear ratios to start with.
They could call it sport plus manual transmission and charge an extra $3000 from the factory, and people would buy it.
#24
Rennlist Member
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I think you have to recall that the PDK based box is a very complex transmission (manual or otherwise) not designed to have ratios replaced...
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
Also as a business, what percentage of the addressable market would actually
want such product if it were technically/economically feasible...
I'd argue its vanishing small; just look at the GT3 market, where the G50 variant
was designed to accept different ratios ... how many people actually do this?
its only really the racers that do
I'm not surprised that no one makes such items
...was more hoping it would be possible to swap out a gear from another model, perhaps.
You know, like putting a 944 S2 gear into a 944 Turbo trans
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#25
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ratios on some other PDK equipped cars, but it would be expensive, I'm not
aware of too many shops that have experience with PDK