Dogbox?

1stalfa · #1 (**permalink**) 03-29-2007, 10:35 PM

What would be the practicality (as a street car) of turning the GTV6 tranny into a Dogbox? As I understand, the tranny's have problems with the synchros as they are the same as what is used on the 4 cylinder versions.

ALso, what is available for a better performance synchro if I was to go the supercharger route, and want to power-shift every now and then. Even though I'm not supposed to. I know, I know, I shouldn't, and I don't want to get a different car either.

**Geezer** · #2 (**permalink**) 03-30-2007, 07:00 AM

Here's a couple of thoughts; If you are concerned about a robust transmission you might consider retrofitting a Porsche 924/944/928 transaxle.

Back a long time ago in another life a friend of mine was a drag racer. He felt that the synchros in his BW T-10 trans slowed his shifts. So we just took them out, bad idea. The trans was undrivable. But we got a bright idea from the motorcycle world. Motorcycle transmissions are non synchro and they shift fine. So we took my Honda 305 Super Hawk apart for an inspection. What we found is that there is quite a bit of play between the gear and the sliding coupling. HMMMMMM.

What we did was remove every other tooth from the coupling on the gear and every other tooth from the sliding coupler. Voila! We had a trans that could be power shifted. We did have durability problems but hey in drag racing everybody expects to tear up the drivetrain.

I believe that NASCAR and drag racers still use "crash boxes". Don't know about road racers. And the standard for the trucking industry is a non-synchro trans, those guys shift without using the clutch. I think it would be an interesting project.

slyalfa · #3 (**permalink**) 03-30-2007, 02:13 PM

Geezer
beat me to it but that is the old common poormans dog box."remove every other tooth from the coupling on the gear and every other tooth from the sliding coupler"
When driving around at a constant speed the box might start to slam back and forth.
I do not know anyone with a street driven dog box so I am guessing here.
on the track it would not matter as you are ether breaking or standing on it.

**Geezer** · #4 (**permalink**) 03-30-2007, 03:13 PM

Slyalfa,

You got on the banging around. When driving one on the street the "slack" can be disconcerting. Further the teeth can beat out pretty quick if you are on/off the throttle while in gear. It will go something like this; power on smooth, power off, wait, bang, then smooth, power on, bang, then smooth. Kinda like driving a car with shot pinion bearings.