I was wondering if anyone is running the UMI On-car Adjustable Control Arms- Poly/Roto-Joint combo? I was looking to run 315's on the rear and I was wondering if the control arm would interfere with the tire or if I could still run the UMI control arms pending what rim offset I choose. I'm pretty sure I'm going to have to mini tub the rear just not sure whether the UMI control arms will give me any trouble or if I'd just be better off ordering them with offset bushings. Let me know what you guys think.

 

Hello,

Thanks for the interest in a UMI product.

You shouldn't have any clearance issues at all with a 315 tire when using the correct off set.

Hope that helps!
Ryan

 

you generally dont need anything close to a minitub to fit a 315 on the rear. but what 315? is this on a 15,16,17 18 19??? If you need a minitub to clear the tire, you will not clear a standard aftermarket round control arm.

But like i said, many people have have 315 rear wheels, mostly done on 17" wheels, and they dont need a mintub. Usually just some hammering and cutting off the bumpstop. And some people dont even do that if the tire sits flush with the quarterpanel lip.

get the wheel on the car first, then see if you need the offset arms

 

I have 315s on 17" x 11" w/7"bs wheels, with the UMI rod end arms & the offset bushings. The standard equal sized bushings woulda make it real close. Mighta cleared, but barely, and I chose to do it once & do it right.

Get the offset bushings. Worst case? You'll have a little extra room, but you won't compromise anything by having the offset ones.

I've cut off the bumpstops & trimmed/hammered some inner fenderwell, but no tubs of any kind.

 

315's on a 17. Dont have rear gears in the 9" yet, so no brakes or axles (cant install them that is). Hence i cant measure what offsets i have to work with... or rims for that matter. I agree with that. I might not need the control arms and panhard bar right now, but when i have money it always ends up spent on other stuff... So id rather get stuff for the car than have an unexpected expense pop up n suck up my cash. Stephen... Your running 7" BS (from your sig pic im assuming positive offset, so your rims are pretty much flush with the outer tire sidewall right? I'd actually like to get rims that are deep dish, or have more of a negative offset.... So what do you guys think i could get way with (negative offset wise) without doin too much work... Like what would be the fine line between a little cutting and a lot?

 

without shortening the axle, nothing. your going to have to use 6.5-7" of bs to get the wheels to fit in the wells. But you really shouldnt order wheels until you have the axles for the housing and know exactly where the hub flange is.

you can use as much negative offset as you want, but the wheels will sit outside the fender, no real way to get a large dish without shortening the axle

 

Nope. Before the widening, they were 0 offset. I can't stand the flatness of the C4+ Corvette wheels. Look like a FWD wheel to me.

Mine were 17" x 9" w/5" bs. I sent 2 off to be widened to 11", so the face still has a dish to them. I coulda had them widened to the outside, but woulda have to had the seam finished smooth & the lip repolished.

 

Im not gonna order rims any time soon. Just tryin to weigh my options so i dont change my mind a bunch of times later... I do have axles just no center section for the 9". So i guess my choices are mini tub and shorten the housing/axles (then i can run a deep offset), or run a deep offset and modify the crap outta the fenderwell, or just run a nearly flush positve offset rim (with no extra modifying)... Alright,thanks guys. (EDIT) SO how big is the lip on your rims? Kinda hard to see from the straight on pic... I was lookin at something maybe like this... Possibly a bit deeper.