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56 wagon
06-25-2018, 09:17 AM
I'm looking at using a set of Fat Man control arms on my 56. These arms are 1 1/2 in shorter per side than stock. This would cure a rubbing problem I have when turning sharply with the tire and wheel combination I am running. (Additionally they have 5deg caster change). Has anyone used these, and have you experienced any problems.
Thanks for any help.

Rick_L
06-25-2018, 11:23 AM
1-1/2" shorter is possibly going to cause other problems. The front end suspension geometry is going to change, primarily roll center and camber gain. And probably not for the better. The other thing that's almost certainly going to happen is that the tires are going to rub on the frame when you turn sharply. So you may not gain anything, just going to hit somewhere else. And you probably don't need a 1-1/2" adjustment anyway.

Heidts also sells shorter arms but I don't think they are short by 1-1/2". I will try to find out how much.

IMO you would be better off solving your problem with a different wheel offset/backspacing or with a brake package that doesn't move the wheel mounting surfaces outboard so much.

Rick_L
06-25-2018, 11:45 AM
Heidts no longer shows narrow control arms for 55-57s on their website. They do show narrow control arms for Mustang II front ends.

But curiously, they are on the Summit website. They are shortened 5/8" according to that site.

chevynut
06-25-2018, 11:57 AM
I'm looking at using a set of Fat Man control arms on my 56. These arms are 1 1/2 in shorter per side than stock. This would cure a rubbing problem I have when turning sharply with the tire and wheel combination I am running. (Additionally they have 5deg caster change). Has anyone used these, and have you experienced any problems. Thanks for any help.

What brakes are you using? Is the car lowered?

56 wagon
06-25-2018, 07:35 PM
The car is lowered 2 in with drop spindles. Wheels will clear on frame. Really don't want to change wheels but agree this would solve the problem. Disc brakes.

56 wagon
06-25-2018, 07:37 PM
I will check Summit again. If memory serves me correctly I believe they have stock caster, will check.

56 wagon
06-25-2018, 07:56 PM
Summit does still showing 5/8 narrowed arms, will follow up, thanks.

chevynut
06-25-2018, 08:03 PM
The car is lowered 2 in with drop spindles. Wheels will clear on frame. Really don't want to change wheels but agree this would solve the problem. Disc brakes.

Do you know how much offset the disc brakes give you as far as wheel mounting surface? What tire size, wheel size, and offset or backspacing? There are multiple ways to solve the problem, you just have to look at all of them and decide which is best and doesn't cause other problems. Maybe you've already done that. :geek:

Here's some options I can think of....

Narrow a-arms
Lower offset disc brakes
More wheel backspacing
Limit steering travel some
Slightly smaller front tires