I know that 15 degrees is considered maximum with u-joints but CV joints can be operated with more angle than that.  Some angle is actually a good thing as it works the grease around and doesn't allow the balls to just ride in one spot and wear there.  I would say that your angle is approaching the maximum that I would want them to be, but I would like to see less than that if you can do it.

Be careful on the amount of angle you get into with CV joints.  I had a friend set one into his driveline on a raised Jeep and the angle was too much and the back and forth on the driveshaft ended up heating up the CV joint to the point where it melted the grease away from the balls and they seized.

He phoned all kinds of experts and they all said that CV joints were never designed for continued angled operation due to the friction built up and therefore possible failures.

Not sure if 15* will be an issue as my friend's was more extreme but it would be something to think about before putting in the effort and expense to get that setup done.

My thoughts anyway.

Cheers
Don

Thanks don, I will contact a CV joint/axel place and see what they think as well.

Dave, I am not sure if I followed what you were saying.  Are you talking about the wheel spaces (+4) and a 3" stretch?

A standard 930 cv is good for about 25 degrees combined angle. That means if it has 5 degrees of setback front to rear, it will only be allowed 20 degrees of droop or bump. If you use the modified joints like we sell on our site, you can get 28 degrees combined.

This is much more angle than a single cardan u joint, but the drawback is that a cv system is much more expensice, and only has a limited amount of plunge.

To be honest, unless you're building an off road car with 21" of travel, or something with an awful trans height, travel is only going to be 8" combined (at the wheel) if you're lucky
Mike