Cut and Turn Pinion Angle

I think theoretically it should NOT make a difference, especially with hard joints. There is no flexing in the axle or the arms, and there's just one link. Sure the pinion will droop one way instead of another, but it should not change enough with the amount of travel pulling and the length of the links. Realistically, if you're okay on short arms you're double okay on longer arms. I chose the passenger side because on such small lift it IS easier to fit, however don't forget about the starter being in the way!

Another thought, isn't there a direct relationship between the pinon and castor angle? When one changes the other will as well? I don't see how you could change castor without changing pinon. As Francesco stated there shouldn't be flexing that would have an influence on the geometry.

Saw this idea on Pirate for clearing the starter. Don't know how that would affect drivability though....

Francesco said:

I think theoretically it should NOT make a difference, especially with hard joints. There is no flexing in the axle or the arms, and there's just one link. Sure the pinion will droop one way instead of another, but it should not change enough with the amount of travel pulling and the length of the links. Realistically, if you're okay on short arms you're double okay on longer arms. I chose the passenger side because on such small lift it IS easier to fit, however don't forget about the starter being in the way!

Click to expand...

in theory it DOES make a difference. in practice it doesnt rear its ugly head. why? i think because of the cherokee's packaging issues and relatively small travel numbers, things stay in an acceptable range. the geometry tends to design itself. and for most people, it is "good enough."

smokeyyank said:

Another thought, isn't there a direct relationship between the pinon and castor angle? When one changes the other will as well? I don't see how you could change castor without changing pinon. As Francesco stated there shouldn't be flexing that would have an influence on the geometry.

Saw this idea on Pirate for clearing the starter. Don't know how that would affect drivability though....

Click to expand...

yes, your castor and pinion angle have a fixed relationship to each other. as one changes, so does the other. a few posts back i said i designed mine to optimize pinion angle. through the range of motion, i get less than perfect castor change. but when crawling, its not the end of the world. the larger priorotiy was keeping the U joint at the yoke from operating at an extreme angle, where its strength is compromised.

as for the photo, the point to point relationship is what dictates the geometry. but the bent arm does have to be able to handle the forces experienced from the road, as well as the force generate from the pinion trying to dive when torque is applied.

Timely post, gents. I have a D44 I need to cut and turn for my SAS S10 so I can finally quit being a poseur and put a front shaft in.

I'll also be putting D44s under my 90 XJ, so this will be useful there too.

Yes, pinion and caster angles are fixed, however with droop the amount of pinion Angle required to keep the what pointing directly at the transfer case changes. And yes I have been thinking about if I need to make a bent link but I will see once I get this axle under the car.