Dog Abuse

[mike g.]

Why would someone do this to a dog ring? Easier shifting? More chance of breakage? Added effort?



?!

[Mike Allison]

Why would someone do this to a dog ring? Easier shifting? More chance of breakage? Added effort?



?!

My guess is they were trying for less rotating mass in the drive line. Not much savings though.
Mike

[Jim Gustafson]

Some Pro teams will make these mods to the dog rings to make downshifts/upshifts easier/faster. They plan on discarding them after a short time anyway. Cars on the sharp end of the grid will often have lots of little tricks like this.

Jim Gustafson

[rmccown]

How would those cuts make shifting easier? less drag?

[CornerSpeed]

For newbies like me, which of those notches in the ring are normal and which are the mods? I'm just curious.

-- CornerSpeed

[dc]

The notches are normal, but every other "tooth" has been removed. You can see the grinding marks where they have been punched out.

Standard MK9 dogring:

[Paul LeCain]

It's not the notches. It's the fact that 4 dogs have been ground off. Makes for a bigger hole for the dogs on the gears (which were probably also ground) to fall into during a shift.

[John Robinson II]

Just curious, what gears was this between, 1st & 2nd? Did they machine off the same lug on the backside? I was told this is to enable lightening fast shifts. Another trick is to just grind some off the top of every other dog. Our FF motors do not produce enough torque to need all 8 lugs.

John

[rmccown]

Iiiiiiiiiiiinteresting

[kea]

This type of dog gear attention, was popular back in the old days, before the dog ears were narrowed. Normally the version that John discribed was used.

[D.T. Benner]

As was pointed out above some people who throw out parts after a few sessions used to do this. I worked on a Formula Atlantic Swift 008 that had all the gears and done that way. I think the feeling was that with 8 dogs spaced closer together there was a bigger chance of the dogs bouncing off one another.

[Steve Demeter]

But with half the ears missing, there would be a big clunk when going from on throttle to off throttle wouldn't there?

[RoadHazard]

As the Great Carrol Smith explains it, having multiple dogs close together makes it harder to shift into gear but makes for a smooth power transfer when you do, Having fewer dogs farther apart makes for a big WHAM! when the gears engage because of all the "slack" space. The whole driveline could make a quarter-rotation before it's truly engaged.

His advice: leave the dogs alone and learn to shift better.

[pmachan]

But with half the ears missing, there would be a big clunk when going from on throttle to off throttle wouldn't there?

Yes, you increase driveline slop bigtime. We went with a 6 tooth ring from a 10 tooth in our GT1 car, I HATED it, way too much slop and we ended up breaking the diff carrier. If you got any rear wheel lockup, it would just clunk back and forth and just destroy stuff.
Mind you a GT1 car has alot more big heavy parts to smash around, maybe its different in a small lightweight car. We switched back to the 10 tooth setup, MUCH better.

[Brian]

They work great in the 2/3 rail of a 5 speed, really slick shifting. I never noticed any increased slop but it was probably there. You can also do that to 1st gear on a five speed and actually stand a decent chance of getting into 1st in anger, rather than just in the paddock.

Brian

[Ricky Racer]

That's an old drag race trick we used in the late 60's early 70's on synchro gearboxes. We removed every other tooth from the synchros and sliders which allowed much faster clutchless shifts in boxes with helical gears that were never meant to be driven that way.