once i roll out of the pit in my race car I do not use the clutch for upshift or downshifting. In certain turns, long double apex increasing radius turns that need a 2nd downshift in them i will heel and toe to not unsettle the car mid turn. Most of our cars are not momentum cars, so the need to carry momentum is not there, its more important to slow down and get on the power early as with the tq we can get the car to rotate and get out quickly.

I tore down the jericho over winter and there was no wear indicated that needed servicing, while shifting like this will require upkeep, its what the transmissions were designed for.

Jake,

This is a dog-ring transmission? (not synchronized?) Is that what we're talking about here?

http://www.circletrack.com/techartic...ech/index.html

Maybe clutch-less shifting has some utility in a dog-ring transmission. I thought we were talking about street transmissions like a T56 or TKO or an RS600.

But the idea that our cars aren't "momentum" cars is false. Our cars driven with the skill that "momentum" car drivers typically have (which means the use of heel-toe downshifting) will be faster. If you're unsettling the car as part of getting to an apex in a turn, you're leaving tenths of seconds out there on the track.

your calling a 3000 plus lb, 600 hp pro touring car a momentum car? Miatas and bmw spec e30 are momentum cars. Watch a rolex gt race or trans am race, they use engine braking, during downshifting all the time, on certain corners they will heel and toe because they can enter the turn at a certain speed but as they go thru it they need a gear change, so AS TO NOT UNSETTLE THE CAR, you would blip throttle and change gears.
Our cars are so fast you need to find the quickest way to slow down before turn in, as to allow susp to come out of bump, and in big hp 3000lb cars this is braking hard and engine braking, it doesnt mean your going slower entering the turn, it means your carrying so much more speed up into the turn you need to do this. But hey what do i know.

Nope. I'm saying that smooth driving is faster driving, which is what I think you mean by a "momentum" car. Drive your Camaro smoothly, carry as much speed as possible through the turns and you'll go faster. Remember that we're not talking about passing during a turn, like in a T-A race where one gains position by out-braking into a turn, we're talking about HPDEs where the cars are separated and measured by lap times.

I see you didn't answer me: does your transmission use dog-rings? :)

jp

i would not shift a synchronized tranny without the clutch ever, total destruction if on the track
of course it is a dog ring transmission. i have a jericho and a t101 close ratio road race trannys.
hpde or not i drive the car as it should be driven.
my 69 with only 420 hp, i drove like a momentum car as i had to, to be fast.
my aix race car is over 600 at the wheels, and is driven like a gt race car as it has to be.
i never mentioned not being smooth.

i think ty is talking about 2 kinds of trannys in this thread.

a dog box will jump into gear when downshifting if you not on the throttle without the clutch, upshifting is similar, no harsh noise, just super fast shifts

Exactly. That was my original point to Ty, and shifting without a clutch on the street isn't at all useful either.

As far as driving styles go, I'll bet there are many that work well. I learned from the guys at Spring Mountain, and we get pulled aside if we drove "GT race" style. They are relentless about smooth upshifts and downshifts, and engine braking isn't taught at all.

Anyway, the best part of all of this is time spent on the track. :cheers:

jp

there are many ways to drive. Using downshifting, correctly you will brake hard, slow speed downshift,slow speed more then downshift again if needed.
not down shift like coming to a stop sign on the street or something when your downshifting and not using the brake, I am talking balls out, you wont make turn in if you dont do it.
I admire pro drivers that drive like that for 2-3 hrs.its a hard thing to do to keep a car that on edge for every single turn,braking point etc. I am not talking tire squeel on the edge, i am talking oh crap i am not going to make it every turn in.
hpde schools teach safe on track driving. Not the fastest way around the track.

How about 5spd or 6spd trannies with syncros?
 

Somehow the question about 6 spds changed to dog ring 4 spds and how some choose to use them. I was hoping (like the OP) to get some more info on high rpm shifting capability, accuracy of gear changes and durability for a 6 spd road race application that uses syncros and is more street capable.

I also prefer to change brake rotors and pads instead of trannies and clutches.

I also have a ZF6 in my c4 corvette track only car and it shifts very nicely but I only use it up to about 6500 rpms. They are just too big to fit in a 70 Mustang trans tunnel, need too much work to adapt and cost a fortune to rebuild.

Anyway - for high rpm use with syncros what works well? I have a POS Richmond 5-spd that needs to go in the trash and want something that works well with a 600 hp 7800 rpm dry sump motor on the road courses. No drag racing is in it's future.

You seem perturbed, but I've actually really enjoyed the slight detour this thread has taken and the dialogue between Jake and John. Some threads evolve like that.

I thought it worth a try to get a bit more relevant tech info before it ends elsewhere. Might have been useful. No worries though -at least it's a spiritied discussion...