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I have a weird question I was thinking about the other day. All our cars are geared to hit ridiculous speeds of 280 km/h. Well, the absolute speed limit in Canada is 100 km/h. So what would happen if you took out all the gears and put in 5 new ones so the car only went to 100 km/h. Would it quicken acceleration? Make it too hard to drive? I guess all the gears would be 'shorter' meaning 1st would max out at maybe 20 km/h, and then 2nd to 40 km/h and so on? Anyway, it was just a dumb theoretical question, I was thinking about. No one would ever do it, but I was just cruising around in 5th the other day at 3,000 rpm thinking, hmmmm, I'll never use this full gear.

:)

 

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Gearing is optimized to keep the engine in the powerband. It is a combination of the transmission gears, the ring and pinion gear in the transaxle and tire diameter this is called the final drive ratio.

It would not make any sense to change five gears when a change in the ratio of the ring and pinion would have the same effect.

A lower gear (higher number like 4.11) would decrease the forward speed of the car for given rpms. This could be helpful or it could not be. If you were running taller tires then it could compensate for the raising of the final drive ratio that the taller tires creates.

This can be helpful only to a certain extent because there are only a certain number of R&P gear combinations available and the number of teeth on the R&P decrease as you lower the gear ratio.

R&P changes are usefull for race cars to keep the engine in the powerband for individual tracks. Curvy slow tracks lower gearing (higher R&P ratio) or a superspeedway would require higher gearing (lower R&P ratio).

If you go too far then you will basically render your first gear useless and your top speed would be lowered as well.

So would you be accomplishing anything in your original question. Not really other than not being able to use 1st instead of 6th or 5th.
 

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Do you really want to drive at redline all the time? You have no desire to drive 149 Km/Hr? I know you don't want your car confiscated but don't you want to know it could be? With even the smart cars cruising(or struggling) 407 at 115, don't you have the wish to say "I can do that in second!"
The gearing wouldn't be as straightforward as you envision. You would try to maximize the time spent in the powerband, say from 4000-7200 RPM.Take the top speed in each gear now and divide by 2.8 would be an approximate gearing to maximize power delivery, assuming Porsche engineers know what they are doing.
You would want some leeway, in order to pass the fool going 99 Km/Hr in the left lane!
This in not something I would consider, I was thinking of a granny 6 gear to improve gas mileage while cruising.
 

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I wouldn't have my cayman anymore plus I don't think you could classify it as a Porsche anymore.
 

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Probably not shift as much. Take off in third gear then to high gear..

Kinda like my grandfathers FarmAll tractor. Not much fun.
 

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I have a weird question I was thinking about the other day. All our cars are geared to hit ridiculous speeds of 280 km/h. Well, the absolute speed limit in Canada is 100 km/h. So what would happen if you took out all the gears and put in 5 new ones so the car only went to 100 km/h. Would it quicken acceleration? Make it too hard to drive? I guess all the gears would be 'shorter' meaning 1st would max out at maybe 20 km/h, and then 2nd to 40 km/h and so on? Anyway, it was just a dumb theoretical question, I was thinking about. No one would ever do it, but I was just cruising around in 5th the other day at 3,000 rpm thinking, hmmmm, I'll never use this full gear.

:)

If you max limit is 100kph, or 62 mph, the first thing I'd do is move from Canada....probably to Montana or Idaho, where they still have somewhat "flexible" speed limits.

If not an option, then I think about four gears would be all that is needed. For max power and acceleration, all you need to do is keep the engine between the torque and HP peaks. Four gears, or maybe even three, should be more than sufficient for this task, I should think....
 

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When I worked in Toronto and Montreal I used to keep the cruise on 70-72 mph and never had an issue. Of course at 5:00 on the 401 the speed is nearer 1 kph.
 

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Install a powerglide tranny:hilarious:As already stated you really would only have to change the ring and pinion gear.I would say that faster 0-60 times could be had.Kinda like a drag car.You would want to find a ratio that allows the car to reach its max power band at the optimum distance down the track or from stop light to stop light.But i do believe that they also have a ticket for that too.....;)
 

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Ask yourself "How fast can the Mounties really go? and do they always get their man?: - If you can't blow the cobwebs out of it once in a while on a quiet road take it to a track with a nice long straight and enjoy the toy you bought.
 

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FWIW, I have tried this in Forza III and it doesn't buy you anthing. As was stated earlier, staying in the "power-band" is the key. The shifts cause you to lose time and actually accelerate slower...even with a PDK simulated. Shifting takes time.

Stock gearing gives you 44 in first and 75 in second at 7200 RPM.

Adding shifts between those points just slows you down.

Maybe having first hit 62mph would get you there quicker...but that is the opposite of what you are talking about.
 

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FWIW, I have tried this in Forza III and it doesn't buy you anthing. As was stated earlier, staying in the "power-band" is the key. The shifts cause you to lose time and actually accelerate slower...even with a PDK simulated. Shifting takes time.

Stock gearing gives you 44 in first and 75 in second at 7200 RPM.

Adding shifts between those points just slows you down.

Maybe having first hit 62mph would get you there quicker...but that is the opposite of what you are talking about.
When you did this in Forza, did you just change the R&P or were you able to stack the individual gear ratios closer? Just changing R&P rarely gives you anything but making a really close-ratio stack keeps the motor near the power peak longer and is generally a big improvement.
 

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Ask yourself "How fast can the Mounties really go? and do they always get their man?: - If you can't blow the cobwebs out of it once in a while on a quiet road take it to a track with a nice long straight and enjoy the toy you bought.
Us Mounties can go fast, it's the darn Timmers that keep slowing us down.
 

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Why not just use the Speed Limit Alert option? Set it to 95kph so that you have a little buffer in case of acceleration. The beep is noticeable and keeps you under 100kph.
 

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Think of it this way...
Truck, Tractor, Earth Mover, Cayman. Get the idea.
 

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I know of a GT3RS that had the ring and pinion changed so that the top speed was lowered from approx 190 to 160 and the reports I have heard from a friend are that the car is awesome. Just 16% shorter gearing but Incredibly fast and geared to usable track speeds.
 

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The other thing to think about is your MPG. Running a car at red line in the top gear and only going 100 KMH is no fun. Been there done that. I put smaller diameter tires on one of my cars and freeway driving was brutal.
 
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