It's commonly referred to as a "Money Shift", I don't think it needs much explaining.

6th gear to 2nd gear would be a mess. Most common is 4th to 2nd and 6th to 4th.

 

IF mis shifts are a concern - think tip

 

Hope Porsche is listening it is TIME for PDK, DSG or whatever they are going to call it

 

Go get a sequential, or learn to shift, problem solved.

 

[quote=turbonator]I've heard that on certain cars (Corvette?, Viper?) the synchros on the tranny won't allow one to shift into a mechanical over-rev situation...don't know if this is true or not.

This is true because the synchromesh in a vett is not as fine tuned as in Porsche (and M3s). With a vette, if the car is going >85m/h and one drops the gear lever from 3rd or 4th to second, the gears grind. Not true with Porsche, the synchromesh are so finely engineered that you can shift into 2nd at any speed with zip grind. And if the car is going 85 or more, the rearwheel speed mechanically brings the engine rpm to over 10K...revlimiter is useless with a mechanical overrev. Downshifting in US- performance cars is often used as a help in braking the car because often the brakes just won't stop the car. But Porsche and BMW brakes are designed to be used without engine help. I learned my lesson big-time with an earlier '95M3. In a highspeed serious accident situation, I thought I could bring the M3 to a stop faster with brakes and engine (I hit 2nd instead of 4th out of panic) and boom a piston hit a valve. Porsches and M3 shift easily into 2nd gear at any speed, so in a highspeed panic situation one has to be very carelful to keep his hands off the shift lever or consequenes cost the driver big bucks. A driver can mistakely crash into a car and insurance pays, but insurance won't pay for that 1/4inch mistake of using a lower gear to avoid hitting the car and perhaps save human lives in the other vehicle.

 

[quote=johnww]Well, I've done it in a Z06 so that can't be true. I was at the track and shifted at redline in 3rd into 2nd instead of 4th. Luckily, as soon as I heard it start to overrev, I immediately had the clutch in and no damage occurred. I think you can do this to *any* manual tranny car.

 

the dealer in Saudi Arabia canceled the warranty on one of the crrera GT because of that

 

[quote=PbPedis]Forgot to mention...porsche's and M3's engines are "interference" engines and a primary reason why so easy to overrev. Pistons are already capable of getting in the pathway of valves. This provides tons of HP with lighter engines. US HP engines are not "interference" and so even if you got the shift lever in a mode for a mechanical overrev, it is doubtful if engine damage would occur at least not the engine damage observed in "interference" type german engines.

 

Valve collision or not I don’t think chunky American V8 or 10’s or any other engine with hydraulic lifters can rev to over 12K rpm. If it goes into a much lower gear the amount of force will be enough to critically damage many valvetrain components. I don’t feel like doing the math, but for the engine to keep up with the tires and driveline from that big of a ratio change would be so far off the tac its laughable. If you make a bad selection when you’re pushing the car the majority of the time your not going to get away with it.

 

[quote=SLATETT]IF mis shifts are a concern - think tip [/quote]
Yeah, but what driver with good hand to eye coordination wants tip??? Car transmission designers can block panic misshifts fine with new SMG/F1 elect/hydralic manual transmissions....no reason this technology could not have been applied to pure manuals as well. BMW says the SMG is the future (pure manuals soon to be dinos) because with SMG trans, drivers can use the left foot for braking which saves precious millisecs in braking performance. An excellent point, but the SMG is crap in my opinion......but can save an engine in a panic situation if that shift lever is moved mistakenly that 1/4" to the left at high speed.

 

I think this is more appropriately called the "MONEY SHIFT".

 

over-revving the engine, Definately will blow your engine up.

 

My 997s is my first owned 6 speed and I am so damn scared of doing this I only have 1300 miles and I dont **** around with down shifting... i dont even know how fast my car really is

 

[QUOTE=johnww]Actually, BMW has backed off of SMG, and has said that the new M3 will *NOT* (ever) have SMG, and will only have 6MT at first. There are rumors that it may have DSG later, but it certainly wont have SMG.

*EDIT*: And I'll add, I personally would refuse to buy any SMG car. I was looking at the E60 M5 briefly, but found SMG to be so distasteful that I ended up at a Porsche dealer buying a 997TT ... 6MT 4 LYF.

 

[quote=winternj]I thought DSG and SMG were similar, just that one is Audi, the other BMW?? What's the difference?