The Stovebolt Site Forums The Shop Area The HiPo Shop Mustang II (part deux)

As many of you already know i've had my fair share of problems with a badly installed Mustang 2 IFS and rear suspension in my 1950 AD truck.

One final question,in ALL of the installations i've seen,the chassis has been 'C' notched to clear the steering rack.
For whatever the reason the person who fitted mine neglected to do this...
How they got everything to fit is beyond me.

Calling the installer to ask is NOT an option because as you can imagine things aren't exactly hunky dory between us.....

Of those with knowledge of installing and driving with these set-ups,can you see anything wrong with the installation on mine.
I have since converted to tubular lower arms to eliminate the wrongly fitted strut rods,but to be frank,i'm still not entirely convinced my truck is now 'correct'.
I'm still experiencing some unusual handling characteristics.....
I've had the alignment done on three separate occasions now......camber,caster and toe.
It still doesn't feel 'planted',which doesn't inspire confidence in wet conditions and even in a straight line,off camber road conditions causes some mild puckering of my nether regions!

I know the lower arms and steering rods should be parallel to each other at ride height but should the top arms also be the same?
Sorry about the poor picture but it's the only one I could find of the offending IFS.

Front IFS

Thanks.

what brand of MII set up are you installing? I have sent off for a set up from CPP for my 50 truck. any help would be great
Pat

Pat,it's a Speedway crossmember,as I say the problem is not so much the product but more installation,I have no issue with the parts.
The instructions do clearly state the chassis must be clearanced for the rack,mine wasn't for whatever reason hence my initial question....

The only advice I can give you is be very precise how you measure everything,tack weld and treble check everything before final welding.

There's probably thousands of vehicles in every shape and form running these Mustang based IFS now,so I can't believe that mine is
correct or else every one using them must either be very easily pleased,or accepts a vehicle that just doesn't handle well.
I understand a 65 year old vehicle will never handle like a slot car but I reckon it should be far better than it is.....

The upper arms will not be in the same plane as the lower a-arms or the tie rods. all of the installs on these trucks have had c notches for the rack. I would get the installation instructions for the crossmember and measure everything to see what is not in place. I have done a lot of these and they are usually a straight forward install.

I think that's what i'll do,to be honest my welding skills back then weren't up to snuff,hence the reason I paid someone to install the crossmember in the first place,don't get me started on the 'bespoke' rear 4-link! (it was downright dangerous)
You can perhaps understand my concerns about the front now....
Thanks for your input.
P.S. I've even considered tearing the whole lot out and fitting a Jaguar IFS!

I do a lot of Must II installs and if they are done properly and with a sway bar they will handle as good if not better than anything else out there. They are simple and work great. I have had to cut out misinstalled must II before, including the first one I did. The first one I installed was such a piece of junk I just cut it off and replaced it. Sometimes it is faster and easier just to start over.

One problem you might be having involves the pivot points of the lower control arms and the inner tie rod pivot on the rack & pinion. Those points should be as close to the same position as possible. If there is a noticeable difference in the pivots, there will be a lot of bump steer. You should be able to deflate or remove the air bags, and move the suspension through its full range of motion with little, if any change in toe. If there is a noticeable change in camber through the range of suspension motion, there are some geometry errors built into the system. One final check- - - -a line drawn through the upper and lower ball joints with the suspension at its normal ride height should meet the surface of the road approximately in line with a line drawn through the centerline of the tire tread. A variation of the intersection points is called "scrub radius" and it should be at a minimum for best handling.
Jerry

Thanks for your input Jerry,I'm aware of the relation of the steering arm/lower control arm to each other,concerning bumpsteer,I learned the hard way on a VW Bug many moons ago I could hardly keep the thing in a straight line!

Regarding the scrub radius,I assume this can be altered by wheel offset etc?

My weekend project is to get the instructions,a tape measure and to check and double check everything. Again!

Yes, within reason. Sometimes scrub radius has to be somewhat of a compromise due to tread width, etc. and the tendency of the tire to contact the inner fenders, wheel to steering arm interference, and such. The further apart the intersection points are at the road surface, the more the tendency will be for the tires to follow ruts in the road and other pavement irregularities. A few years back the fad was to install very small-diameter wheels with wide tires on some of the riceburners, with the tires stuck out beyond the fenders a few inches. Those things were impossible to align, and they were terribly unstable.
Jerry

I didn't manage any garage time yesterday Jerry but I have been experiencing 'tramlining' as I know it.

On some road surfaces it behaves much like it has old bias ply tyres,rather than modern radial tyres.

I will check that thoroughly.

Thanks again..