Difs measured: AP2 purchased brand new from Hartopguy, from and IN TRANSIT WRECK. This dif was not built or ever touched, just removed and sold to me with the original flanges in place.

AP1, measured TriaXemginE's dif as the car is here and up in the air.
Confirm by my TriaX"enginE" thread in Metro, as I am changing the engine as we speak.

THIS IS FACT! Anybody wanna get out a ruler and try for themselves?

 

If I may, I will retract this statment.

I'll keep this unbiased, and go with 100% fact.

Once they are all listed, it will be very clear to me and the rest of us if the spacers are beneficial.

 

The facts, all the facts, and nothing but the facts.

 

Good info!

 

X2 very informative thread, now if we can only have these threads with all mods.

 

The car I have coming in on the 18th I need to remove the rear susp assys, and loosen all the rubber torsen bushings. Definitely the best time to measure axle movement, from full suspension extension to full bottom out.

Does anyone else have difs laying around to take more measurements?

I can measure an 05 dif next week, and another AP1 dif this week when VenomousS drops it off.

 

Thanks Billman...another myth busted!

 

*instert tire squealing sound*... I'm no expert

I'm just looking at it from a mathemetical point of view.

I do know the axle is not moving axial because (I'll say it again) it is kept in place by the outer CV.


Billman can now fill in the numbers

 

I nominate SpitfireS as our unofficial S2kI draftsman.

Here is a good general discussion of CV joints for those who might want to understand them a little better. Tripod joints like our inner CV joints are discussed well enough to get a good feel for what's going on.

SpitfireS, your drawing has helped me figure out what it was about all the spacer theories that bothered me, and after playing around with Pythagoras for a while I understand EXACTLY what the spacers do. What Bill is going to discover when he measures is that the spider is closest to the outside of the cup when the wishbones are most nearly parallel to the ground. From there, as the wheels move up and down, the balls will move further inward. I'm working on a writeup to explain why this has to be the case, why it cannot be otherwise, and what the implications are for the spacers, but it may take a while, because I need a draftsman to do some drawings to help with the explinations. Many of you are going to be quite surprised, and I'm surprised it took me this long to figure this out.
Thanks SpitfireS!

Now, I need somebody with drafting skills and software to help me out. The ability to create animations would be helpful. Anybody want to help out?

For now, the two images below show how any unequal length arms and half shaft interact as the suspension moves upward, and it shows clearly that the spider MUST move deeper into the cup as the car is lowered. The spacers move the cup out further, making the spider ride even deeper into the cup. To get the spider back to the orignal point in the cup you'd have to make the flanges on the differential narrower rather than wider. Hopefully somebody will be able to help me come up with better drawings and maybe even an animation that will show how the spider moves in and out as the suspension moves up and down, but until then, this will have to do. If it's not clear, don't ask; I'm working on a better explination as time permits.





See how the spider (the left end of the longest <5.00> line) moved to the left as the wishbones moved upward?