How do straight cut gears eliminate the need for a clutch? Unless the inside of the Porsche transmission is completely different all others I've been inside of the gears don't actually move. Just the syncos either lock or unlock a gear to the shaft. So the gear mesh between gears whether heli cut or straight cut seems like it would have no bearing at all as they never un-mesh and re-mesh with each other.

 

which part of my comment confuses you?

in order to ditch synchros people swap to gears that use dog rings instead of synchros and those are usually straight cut gears which are much stronger by design.

 

The part where you said you have to use straight cut gears to use no clutch. It would seem getting rid of syncros and using dog rings is what allows no clutch. The fact that the gears are straight cut has nothing to do with it. They could still be heli cut with dog rings and work with no clutch. That's all. Just threw me off which is why I was asking for clarification.

 

That is what I said
i have never seen people using dogring gears that are heli cut. i am sure its possible but people that are interested in dogrings are probably not going to waste their time with heli cut gears.

 

Probably. I'm not familiar with dog rings is why I was asking. All you said in your first post was straight cut gears are needed for no clutch. It just had me wondering how. I got it now Thanks.

 

My big rig has straight cut no syncro trans. You either double clutch or te the Roma and shift without the clutch. The only time o ever use a clutch is on takeoff

 

Nice, sounds similar to my R6. I only use the clutch when putting around town, when I get it opened up you just shift I don't know the specifics of how that transmission looks inside though.

 

I've actually heard that this shifter isn't any faster and is possibly slower. The only difference is eliminating the miss shift. Kong has it in his car, I talked with him when looking at shifters.

 

Did some reading on transmissions to refresh about dog gears etc= these posts make me think which is a good thing lol.

 

The SQS shifter is a very clever product but will generally not be any faster (possibly on the dogleg 2-3 and 4-5) than the factory H pattern in the hands of an accomplished driver that can heel and toe quickly. Your limiting factor will be the synchros. You can actually stift the stock H pattern a little too fast for the synchros so common sense dictates that the SQS won't make it any faster, without the expense of being hard on the synchros. Additionally, the SQS evidently won't eliminate a miss shift either contrary to common belief. In theory yes, but in the real world, evidently no. You are still dealing with electronics and the added complexity can and in some cases does malfunction. One just has to keep that in mind. Here is a link to a post (#81) that details the SQS going into neutral on downshift instead of into gear and thus resulting in a 10K+ over rev and and ensuing engine rebuild. Probably an isolated incident but it can happen.

http://rennlist.com/forums/997-gt2-g...ct-yoda-6.html

 

Noob question but how does the motor over rev in neutral? Does it not have a rev limiter in the ECU that either closes the throttle (it's an electronic drive by wire unit) or cut spark or something?

 

i would tend to agree with you on that statement. guys need more seat time and that will eliminate misshifts. the only way i see this shifter being beneficial is with addition of dog ringed straight cut gears to use it without a clutch. I've driven a car with this shifter and it actually annoyed me

I dont see that either, in neutral it should only go to redline. Only way I see a over rev like that is a mechanical overrev which forces the motor to spin up that high coming from the transmission.

 

If you have a LWFW and other lightened rotating components in the engine, your engine will spin up very quickly. In other words, the inertia of the accelerating engine will carry it over redline. Try it. Put your car in neutral, and stomp the throttle to the floor and keep it there. You'll be surprised how easily the momentum of the engine with no drag on it will carry it past the fuel cut off. A stock engine with a heavy dual mass flywheel will not rev nearly as fast as a built motor with lightweight rotating components but with no load on it, it will still fly right through red line by a several hundred RPM. The example in the link I posted was on a high and fast revving built GT3 engine so not a true comparison but you get the idea. Think about it, even in 1st gear these cars can exceed redline/fuel cutoff due to their momentum, much more so if there is no load on the engine whatsoever. My motor has a lightweight RSR crank along with lighter pistons, rods, LWFW, LW pulley. It revs extremely fast and I can easily zing it past the rev limiter in neutral.

 

I think it is faster than stock shifter ,specially from 2nd to 3rd:

 

Ah OK, very interesting. I haven't exceeded redline in this car yet so I'll take your word on that Interesting that once fuel is gone it can continue to accelerate and continue increasing RPMS. I can see maintaining RPMS from inertia but to keep increasing RPMs much more than 1 or 200 RPMs is new to me.