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Old 06-27-2019, 11:05 AM   #88
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Originally Posted by eagleeyes221 View Post
I have a Cusco type RS. Went from a 2 way at 100% lock to 1.5 way at 60% lock. I didn't mess around with any of the preload springs as i could pull the diff again to make any changes if needed. I am curious to see what the difference in feel is between a 1.5 way and a 1 way diff is. Thats interesting, im looking forward to the next update now
Yea the M-Factory is basically identical to the RS. And you made the right decision to go to those settings if it's anything but a drift car.

You lose some preload when you lower lock % so if you want to keep the same preload as before, you'd have to add 2-4 more springs. The lock % and preload amount are interdependent.

But, speaking of Cusco, their literature is what made me realize something that M-Factory mentions nowhere and their US office hasn't replied back to me on yet.

So I noticed this notch on the deceleration side of the 1.5 way ramp at the start of all this, but didn't think anything of it at the time (pre-Watkins Glen).

Taking a closer look at how the "cross shaft" mates up against the deceleration face, it made sense as to why this notch has developed. It's sharp edge contact:

So post Watkins Glen it got me thinking because the diff always acted the strangest in deceleration when turning (slower turns). That notch could be affecting function and causing weirdness.

Then when going through Cusco documents, I stumbled upon this diagram that shows the cross shaft is actually reversed with the more angle/curved side against the deceleration ramp on the 1.5way:

There are just pictures and diagrams that show this. There's no actual wording that mentions that this needs to be done. So, I flipped the cross shaft to see what it would look like.

Looks like meant to be if you ask me:

vs this:

Looks pretty obvious. So, I assembled it that way only to realize that the stack height of everything increased because the cross shaft contacts the ramps in slightly different spots when flipped (you can see the spacing of the ramp plates is slightly larger in the pics above). To get it to work this way, I'd have grind down the washers at the very ends of the clutch stack. I bailed and just set it to 1way for the New Jersey race for the time being.

This makes it seem like that perhaps it isn't correct to flip the cross shaft, but I'm convinced that it is based on the few things mentioned above. Cusco even shows it flipped in their diagrams. I'd bet that there wouldn't be an issue with a Cusco RS doing this since the contact points would make it the same stack height when flipped, as that is what they show to do.

Anyway, thought it was worth sharing..
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