Mustang II control arms

416Ford · February 20, 2014, 02:09:17 PM

Going to be working on the front end of my car here in a few weeks and would like some input on 5/8" narrower control arms.

The brand battle will be one issue. This is what I am planning on (Ford Mustang 2 Tubular Control Arms for Coil Springs - Black Finish [APSPS500Complete] )

I have already had issues with the needing wider parts them most. The MII cross-member was purchased back in the early 90's so I don't remember who I purchased it from.
When I installed it in the car I had called them to complain that it was to wide to fit in between my rails and they told me my car was hit and the frame was bent. I disagreed and cut some of the inner cross-member out to fit the frame.
15 years later the car is on the road. Chassie engineering sway bar #SB-4148PM was 2" to narrow so I had to order the wider one. Stock Mustang rack was to narrow for the alignment so I had to order inner tie rod extension kit.
Now I want to lower the front end so the car does not resemble a gasser.

My rims are available in two narrower sizes. One gets me a 1/2" clearance and the other is only 4" and I don't want that narrow of a wheel on Michigan roads.

So what kind of issue am I going to have with the narrower control arms?
Things I am assuming:
I will be welding the lower control are kicker on under the finished car.
Cutting off the torsion bar mounts on the frame.
Removing the tie rod extensions
New alignment
and I may still need to buy narrower rims and tires.

What am I missing?

416Ford · February 20, 2014, 03:49:05 PM

Missed this info the first time.
My current wheel and tire setup with one coil out of the spring leaves me with only a ¼" of room between the tire and inner fender lip.

Old picture but this is with the coil removed springs.

Charlie Chops 1940 · February 20, 2014, 04:09:15 PM

An M-II kit for that chassis, for stock length M-II a-arms, and stock length M-II rack should yield a car that has room for "normal" offset wheels up to 7" wide in the front, for sure 6". Something is not adding up. My take is that the originally purchased M-II cross member was incorrect more than one way.

I think you need to determine if the upper and lower a-arm mounting locations are correct from side to side. I think you can look at Welders Series installation directions to get that information. Enjenjo proably knows that by heart.

Too wide cross members may require lowered a-arms for clearance purposes but combined with different suspension pivot points poor results will be norm not the exception. Re-look from day one.

Charlie

416Ford · February 20, 2014, 04:29:40 PM

Charlie, the issue I have now is the measuring part. With the engine in the car and front clip on it, I can not measure anything except the parts attached to the control arms.
Sway bar mount was 45-1/2" eye - eye.

Charlie Chops 1940 · February 20, 2014, 04:51:12 PM

You should be able to measure the lower a-arm mounting holes from underneath in front. The eye-to-eye measurement of the sway bar doesn't mean anything to me, or to the parts installed already.

Charlie

enjenjo · February 20, 2014, 04:54:22 PM

This number, APSPS500Complete, comes up as stock length, not narrowed. They do show a narrowed arm kit, but only in stainless steel.

I am assuming you don't want to change the whole cross member so lets try to work with what you have.

46 to 48 Fords are notorious for for variations in frame width. BIG variations! so having to modify the cross member is not unusual. That said, even with the Variations, I have never needed tie rod spacers to make them work.

If it was me, I would get the shorter lower control arms, and if possible, if there is enough room, use the stock length upper arms. Using shorter upper arms increases the camber gain, and tips the tire in at the top. In most cases you can cut the slots for the upper bolt further in, and use the stock ones.

If you use the control arms that eliminate the strut rod, make sure you have tabs from the outer ends of the bolts to the frame so they are in double shear, and transfer the braking loads directly into the frame rather than twisting the cross member, which causes cracks in the cross member.

There should be enough adjustment in the outer tie rod end to take care of 5/8"

Charlie Chops 1940 · February 20, 2014, 04:54:23 PM

Again...go to Welder Series web site, then look at make your own. It gives 4 or 5 critical measurements for an M-II design.

Charlie

416Ford · February 20, 2014, 04:56:30 PM

Yes, I should be able to get that measurement.
I was thinking shock hole location is one that should be the same but I am not able to get.

How's the 40 coming along?

416Ford · February 20, 2014, 05:07:05 PM

Thanks Charlie and Frank. I will double check some measurements first then look at the options again.

Frank I must have clicked on the wrong control arm tab when I copied it.

kb426 · February 20, 2014, 07:29:22 PM

416Ford, are you close enough to drive to Frank's and let him look at it? I believe he could help you enough to justify the trip.

416Ford · February 20, 2014, 07:29:58 PM

Well I am still looking for the dimension on Welders Series but it is 23-1/4" C to C.

Found it. Should be 22-1/4" Hummmm.

416Ford · February 20, 2014, 10:10:58 PM

Quote from: "kb426"416Ford, are you close enough to drive to Frank's and let him look at it? I believe he could help you enough to justify the trip.

Franks is only 4 or 5 hours from me but I can barely get me 4wd out of my driveway.

Engine is torn down also. Had to repair the heads on it.

416Ford · February 21, 2014, 01:02:23 PM

Quote from: "enjenjo"
If it was me, I would get the shorter lower control arms, and if possible, if there is enough room, use the stock length upper arms. Using shorter upper arms increases the camber gain, and tips the tire in at the top. In most cases you can cut the slots for the upper bolt further in, and use the stock ones.

Won't the longer uppers lean the tire out at the top?

Any idea why my cross-member is 23-1/4" CtoC ? Could it be a 46 Ford Truck cross-member?

Yes I know the bolts are in upside down. It was just to roll around.

enjenjo · February 21, 2014, 07:43:50 PM

I just got off the phone with El Polacko.I looked for my Mustang crossmember jig, but could not find it,so I called him for the correct control arm bolt spacing.

The bolts should be 21 3/4" on center. So you should have enough room to redrill the holes in the crossmember, and use the control arms you have. The left side rack bolt should be 4" from the left lower control arm bolt, so that may have to be moved.

QuoteWon't the longer uppers lean the tire out at the top?

Cut the slots in the hats further in, that should move them in enough to line things back up.

Looking at your pictures, you should have a larger C notch for the rack boots, box them with a piece of tubing.

The strut rods may need to be tweaked to line them back up, a little heat should handle it.

A little more about control arm spacing. Original Pinto crossmember were 21 1/4", Mustang crossmembers were 21 3/4". So your crossmember is 2" wider than stock. Some manufacturers did the to assure spring clearance to the outside of the framerail. So if you narrow it, make sure the springs don't rub the frame. If you have that problem, it's an easy fix.

Post a picture of your sway bar, and we can see if it can be narrowed to line back up.

416Ford · February 25, 2014, 09:44:10 PM

Frank, thanks for the information.
I would have replied earlier but I am installing drywall in the house and trying to fix a broken variable speed control on my bobcat at night when I come home from my paying job.

I did crawl under the car tonight and look at the cross-member again to see if I could move the holes. Not an option. The lower control arms mount in tabs that are welded to the end of the cross-member and there is only a 1/2" of space available before the control arm would hit.
The top hats look like I can move the uppers in and open the slots if needed. Also looks like enough room for the spring to move in up to an inch before it hits the frame.