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2G 10 sec trans. who should I go with?

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Jon is hit or miss call or email him I know hes busy in my case hes 15 minutes from me, second trans from him for what I use it for I love it and this one even more once I break it in.
 
It tips loads the gears.

I think I understand the notion behind tip loading the gear teeth. Many just drop in the Evo III 3rd and 4th gears in certain applications (i.e., 92’ DSM W5M33) straight up with no other changes. This may cause issue considering the intermediate 3rd is the transmissions final drive gear and, if, the gear teeth are not meshing properly with the DSM components. It’s my understanding that when utilizing the 3/4 Evo III gears with the corresponding Evo III intermediate shaft (and possibly center diff.?) this should not be an issue. Not sure if I’m on the right track here…please give further clarification on the cause of the tip loading issue present with utilizing the Evo gears…
 
I have never had a chance to compare the Evo III gears/gearset to their respective DSM counterpart and it may be helpful to get clarification from those who have a better understanding. I know the Evo gears have more meat on the root radius of the gear teeth (vs. L91-E92 DSM) and that attribute may increase its ultimate strength. Some have claimed that the Evo III 3rd gear having one-less-tooth than OEM DSM somehow translates into it being “stronger”?—never heard an explanation or ME principal behind this claim. Moreover, my understanding is that the DSM and Evo III 4th gears are both undercut to fit the bearing on the shaft…read a post claiming that the Evo III gear is narrower than the DSM, unsure if this is true. Anyone happen to know if the DSM gear(s) are a physically wider gear than the Evo III (incl. measurements/undercut)? Also, anyone feel free to offer insight on intermediate shaft differences as it pertains to strength (DSM v. Evo III?).

It would be very useful to ascertain which gear/transmission component combinations work best. I think it would be a good discussion to have considering the OPs 10 sec parameter and as such determine if utilizing the Evo III gearset, whole or in part, offers any viable increase in durability/longevity or design functionality over the others…I think the questions in this post are a good start.
 
As far as I know the Evo and Dsm is the same shaft and cd housing. As far as the gears go, I've never had them in my hands, so I can't comment on the root radius. But what I do know is there's almost no way anyone can just look at them and tell you which is stronger without reverse engineering it. Perhaps some gear design expert can, but that's outside the realm of any Dsm trans guy I know. In fact that's outside anyone I know, even in my job.

Anyway I can tell you that either the evo3 gear is weaker than the Dsm gear, or the intermediate shaft design is compromised to work equally shitty with both gears. If you set it up so that the evo3 setup is perfect, it would need a radical profile alteration with a tip modification on the Dsm gears, which they don't appear to have.

If you made it so they are both compromised, the Dsm 3rd would have a reduced pitch circle, with thinner teeth and the Evo gear would have an increased pitch circle with a tip modification. I think in that case there it can distort the involute, and have more sliding motion than rolling motion, which hurts fatigue life. Either way you can't have them both work good. Either one is shit, or they both are.
 
This is interesting and I understand it gets really complex. Aside from sending these gears out to a gear design expert for analysis, I figure we can get some insight by looking at the following values:

a. Gear pitch
b. Face width
c. Number of teeth

These seem to be the major variables. The others for all intents and purposes being constant i.e., tensile strength of material—then plug those values into a gear strength calculator, to work out the calculus with the Lewis formula. I am most interested in how strength is affected by these values (e.g., Evo III gear having 1-less tooth, pitch of 1990 gears, etc.) and how that equates into overall gear strength respectively.

From my research it looks like there where two versions available in 1990; pre 03/1990 and post 03/1990. I may end up experimenting with these. At this time I am unsure if one or both build dates are the larger tooth stronger gears people have alluded to?

Ideally, the pitch is 2.25 times the height of the teeth on a well designed gear with strength in mind. The distance between the center of one tooth tip to the center of the next is pitch…so anyone with the 1990, L91-E92 and or Evo III 3/4 lying around that has a dial indicator, digital caliper and is willing to count teeth please chime in. This is unlikely to get a response LOL. Not sure if Mitsu publishes this data or not or if people on here happen to know some or all of these gear specs (a.,b.,c.)…nevertheless IMHO would be quite valuable to know!
 
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Update john from tre just called me left a voice mail. I missed it because im working. But he says he has what i need.
 
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