Originally Posted by onefastviking

I think some people would, and could, make a point for getting the trans. input shaft up to speed would not be a wasted motion or time.

Originally Posted by mpaton

OK, thanks for clearing that up.

Obviously, there's more than one way to downshift more than one gear at a time.

That being said, they way in your interpretation is the most abominable I can think of.

It is very harsh on either synchros or dog clutches, and it could easily result in revving the clutch center plate twice as fast as the engine's own red line. Clutches have their own rev limits and can come apart if over revved.

If there is a proper way to downshift more than one gear at a time, then it would be to simple miss out all intermediate shifts except the one to the desired corner exit gear, and to delay that one until the clutch can be lifted immediately after the gear lever is in the correct gear. This is no harder on synchros than any other downshift, carries no extra penalties for foot slipping off clutch than any other downshift and doesn't rev the clutch plate faster than the engine.

In any downshift I consider it important that the clutch is not pressed any longer than may be required to effect a good quality gearchange, so I strongly disapprove of driving with the clutch depressed (as would be happening in Dave's interpretation).

I also consider it good practice that the car always be in the "correct" gear at all times, so that a suitable amount of drive torque can be applied in the event of unforseen circumstances.

So I consider a good implementation of skip shifting to be merely less than desirable, but I do consider your interpretation of it to be an abominably bad practice.

Originally Posted by onefastviking

I think some people would, and could, make a point for getting the trans. input shaft up to speed would not be a wasted motion or time.

Originally Posted by KaiB

May we get to the real question here?

At what point in the braking sequence should the downhifting be completed?

Originally Posted by Matt Romanowski

^^Watch people enter Big Bend at LRP sometime. It's very telling.

Originally Posted by utkinpol

with me it is always an issue with brake-to gas transition there when i try to do double apex with fast entry and late trailbraking - at transition moment going back on gas front wheels loose grip big time, i cannot make a trick to keep them under load there so i have to get too slow mid-corner there to make sure front will bite.

simple workaround is to do a single apex trying to maintain same bank angle but it does not feel to be 'fast' and requires much slower entry speed than double apex way. i guess no one would give a universal answer about this but it is an interesting topic nevertheless, of how to do big bend in a heavy *** 996/997 car.

Originally Posted by Veloce Raptor

Kai, as I mentioned, my view is to do in in the second half of the brake zone, and I coach to this.

Originally Posted by Veloce Raptor

Kai, as I mentioned, my view is to do in in the second half of the brake zone, and I coach to this.

Originally Posted by KaiB

Do we want all downshifting completed prior to turn-in, i.e. during the "hard braking phase" and just proir to entry as the pedal effort softens as trail braking occurs?

Of course with my nasty rear brake bias, rotation is a non-issue...it's merely a matter of the direction of rotation!!!

Originally Posted by Veloce Raptor

Kai, as I mentioned, my view is to do in in the second half of the brake zone, and I coach to this.

Originally Posted by Matt Romanowski

If you're losing front grip when you transition to throttle, something is wrong.

With the repave, everyone I've seen runs the double apex using just about the whole track. 996/997 should be no different.

Originally Posted by KaiB

Do we want all downshifting completed prior to turn-in, i.e. during the "hard braking phase" and just proir to entry as the pedal effort softens as trail braking occurs?

Originally Posted by Veloce Raptor

Again, all true in theory. However, I still don't like skip shifting, regardless of how elegantly it is done. Let's use T1 at VIR as an example. In a 993, I am going from 5th to 2nd there. I always row 5-4-3-2. I like to know what gear I am in, and in fact if the unforseen happens, I can still make the corner, albeit at sub-optimal velocity in 4th or 3rd if need be. Again, JMHO, YMMV.



True. But to be clear, what I showed Greg (at VIR, into 1 and 14/14a for example) was a very, very quick sequence where it was BamBamBam with blips that nearly merged into one another, in order to keep the input shaft spooled. If you do it slowly, there is real danger, but if you're fast, it can work well. Again, JMHO, YMMV.

Originally Posted by bobt993

T1 in 2nd in a 993? That turn is a bit faster than that don't you think?

Originally Posted by forklift

I take T1 at VIR and SPR in 2nd although my gearing is slightly longer than a 993. About 72 in 2nd but 3rd is about 104 and bogs down too much. My min speeds through both when I do them decently is around 47-48 mph. If I ever decide to do a 4.00 R&P I'll take it in 3rd which would lower 3rd to about 90ish....which would help in over slowing I would think...meaning I am still doing this a bit in 2nd. I'd like to see 50 min in each.

Originally Posted by bobt993

Jim, I was figuring 60mph min apex through there and with a 6spd 993 that would put a stock 993 box at 68mph with a rev around 6500 rpms. A custom 2nd may hit 80mph, but that requires a new main shaft. Using the fast entry as Chris has school'd would be tough with the car that close to redline at turn entry.

Tbolt has the same situation in T1. Entry in 3rd usually lowers the apex speed to much in my car, but using 4th gives better decell and smoother exit. I put a taller 2nd in my trans, but I seldom use the damn thing even at Summit.