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Irishrally
1st March 2015, 19:57
Hi there,
I'm new to this forum and this is my first post so please take it easy on me :)!
My question is regarding gear boxes, and what I want to know is, what is the gear box that you would consider to be the gearbox that would give the 'purest driving' possible?
I'm talking about a gearbox that the driver has to do everything in (as opposed to sequential gearboxes and autos).
I have heard about synchromesh gear boxes and Dogboxes, but are there any further types of transmissions similar to these?
The reason for my question is that I want to put a gearbox into a rally car that will require me to do everything in the gear shifts (hence a 'pure' driving technique), but still be strong enough to with stand all the beating that it will take.
I have read that Dogboxes are good for this, but some sources say you can't change gear like in a synchro, where you lift off the throttle and use the clutch on shifting, but others say you should?
Also would a synchromesh gearbox not be suited to rallying?
Any help is appreciated! Thanks!

Mirek
1st March 2015, 20:26
Even with dogbox You don't need to use clutch (although many use it for reliability reasons).

I somehow don't understand this hunt for the only true and pure classic rally experience. For me it's weird. Something like if I come to a train station and insist on a steam machine to carry me home because the only proper train is such which makes a lot of black smoke. But ok, de gustibus non est disputandum :)

janvanvurpa
2nd March 2015, 06:31
Your question is entirely too vague and if some people want to get all whiny, not about WRC, which this forum is supposed to be about..

That said, don't be cagey and vague, tell us the car, the box options--and links to the gear set you're thinking about, and the class, and your experience level, Context is everything and the answer depends on context

br21
2nd March 2015, 09:48
you can have typical synchro gearbox, like in normal road car. usually not very strong for rally application (depends on car and its spec of course). Then you can have dogbox, so no synchros, but dogs instead, so gear changes can be much quicker, gears always go in, etc. Usually dogboxes are with straight teeth, so also stronger, but louder. And then you can have sequential so same gears like in dogbox but different shifting mechanism - push/pull instead of Hpattern. So no misshifts, etc. And then you can have evolutions of sequentials, so with cut-off sensor or with paddles. For dogboxes you don't need to use clutch.
That's short descripton of course.

Zeakiwi
2nd March 2015, 12:37
Rally people have run the (2nd generation 2001 on ) Subaru WRX standard manual synchromesh gearboxes that came with the road car they converted into a rally car.
There are close ratio synchromesh gear kits for extra strength.
http://quaife.co.uk/quaife-products/motorsport-gearkits/ (explanation of trans etc)

Even the strongest gear boxes in motor sport can fail due to nature of motor sport with cars going over jumps. Most teams have a spare transmission or more ready to go in the car.
Pfitzner gives a demo of the dog box in a road car.
http://youtu.be/n_1jO64tuQA (Pfitzner)

Mercedes used automatics in their 450/ 500 rally cars. Now with the electronic automatics it is possible to put micro switches in some autos and have them stay in a 'gear' until manually 'shifted.