Cut Engagement Teeth
There is an old manual tranny trick of removing every other dog tooth on the gear and synchro slider to make for a shift a lot like a dogbox dog engages. You can shift it without using the clutch or lifting off the gas. It’s an idea that works and works very well for some trannies, but not on a DSM. We have been trying to get this to work, but the problem is there are an uneven number of dog teeth (39) on the gear and slider, so you can’t cut every other tooth off and have it synch up correctly. If every other tooth is taken out, there will be one spot where there will be two that are cut and you will have a 1 in 9.75 chance of hitting the teeth in just the right spot for it to operate like a dogbox would. I tried it anyway in my own trans, and it felt the same as a regular synchro, and I don’t think I ever hit it once the right way any of the times I was racing the car to get that really fast shift. Good idea, but won’t work on the DSM ? Here is a pic of the old gear we tried to play with. You can see, because of the odd number of teeth, the area where the two dog teeth are ground down. The slider was also cut in the same way.