Crown Vic IFS - How to Set Up LCA Rear Mounts?

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Aerocoupe
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Crown Vic IFS - How to Set Up LCA Rear Mounts?

Post by Aerocoupe »

So this is a question not a how to. I have read several threads on multiple forums and it seems the most common way is to rotate the "barrel" on the stock bushing mount so that you can install the rear bushing flat to the frame and have some adjustment on the caster. Sean aka Hackster has a build thread on here where he opted to mount it flat then on another build over on http://www.ford-trucks.com (his 3rd F100) he did them at the factory angle and from what I can tell he says he likes it better for alignment reasons. Sean if you read this man I would really like to hear your thoughts on this as you have done it both ways. I also ran across Outcast Autoworks new brackets (https://www.outcastautoworks.com/col...ol-arm-mounts) which look interesting but I can fabricate my own so not going to go that direction.

So this is what I know:

1) On the LCA rear mounts the centerline to centerline distance between the end of the studs on the LCA's when mounted in a CV is 33".
2) From the factory the CV is set with 5.25 to 6.75 degrees of caster.
3) So if you wander around on the net and get on http://www.mercurymarauder.net you need to get Carfixer's alignment specs which set this front end up correctly and they are as follows:
For best tire wear, here is what I use on all MM alignments:
Camber: -.3 to -.5 degrees.
Toe: Zero degrees.
Caster: 5-6.5 degrees positive with .3 degree lead on the right side.

These guys push the MM's way harder than the CV's and have wider tires so these are the specs I will provide to the alignment shop. I also have ADTR's camber kit (https://adtr.net/product/mercury-mar...gnment-bolts/) which is SPC's kit with Chris' upgraded hardware so I should have all the adjustment I need.

I understand that camber is defined as the angle between a line drawn through the centerlines of the upper and lower ball joint and a perpendicular from the ground where the ground is dead level. Positive caster means the upper ball joint is further to the rear of the vehicle than the lower ball joint and negative caster is where the upper ball joint is further to the front of the car than the lower ball joint.

Where I am stuck on the CV IFS is how to set up the initial caster angle. I haven't seen any install cover this in depth other than the different ways to mount the LCA rear bushing which does give some adjustment but you need to be around 6 degrees positive on the initial setup as my understanding is with the control arm centered in the stock bushing you have +/- 0.5 degrees of adjustment. So if anyone has any advice on how to set the initial caster setting I would be interested to hear how you did it. I am going to use a piece of angle to space the ends of the LCA's apart 33" but other than that I am struggling on the caster issue. I may be way over thinking this but I know this is critical.
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