The Strobe slipper is the best available, but matching that low ratio would be pretty tough(requires an 8.5 tooth pinion, which is too small for a mod1 pinion due to the larger teeth). I carry mod1 pinions as small as a 10 tooth, and could get a bore reducer to make it fit the HV maxx motor shafts(1/8"). The slipper comes with the needed pads, and uses the stock spring and pressure plates. Only 4 additional 3mm screws would be needed to mount the ofna spur gear to it.

Could I make up the difference with a bigger spur gear?

I suppose you could, so long as it will fit. i have a couple ofna 66 tooth spurs(I think, maybe 62 teeth?) that should bolt to the slipper. Whether or not they clear the drive cups would be the next question. I will do a mock up to see if they would work.

Please do and let me know. I have this brand new chassis, diffs, and cvd's I want to break in. I really don't want to lock the slipper down again. I think that's what started all this in the first place. :)

It is a 65 tooth. It clears the drive cups, too! About an 11 tooth pinion would be the same reduction(which I don't have). A ten tooth would be a little slower(more reduction 6.5:1), while a 12 tooth would be slightly faster(slightly less reduction 5.4:1) than the 12/72 (6:1 reduction).

Excellent! Would you send me an email with the total including a 12 and a 10 t pinion.

mynameisyournametoo at netzero dot com

what about modifying a traxxas spur to fit the strobe , would only req presice drilling of 4 holes and dremel out the rest , would this be possible , then all 32 pitch pinions would be avail

You need some proper tools to make the hole perfect in the middle.

what exactly does the sprong kit do?

I think the idea of the sprong is to keep a more even pressure on the plate and pads.-for more consistent performance/amount of slip.(i'm guessing)

That is exactly what the sprong does. More even, consistent pressure on the slip pads.

sorry little confused what kit do you need for the emaxx
the storbe sprong kit $12 or the strobe slipper kit with bearings $32?

you NEED to have the slipper kit but the sprong is optional. all it does is replace the spring. you dont have to have it although its a good idea.