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Discussion Starter #1
So I replaced all of the suspension, steering, and power steering components, but the handling still leaves quite a bit to be desired. Getting up over 65 mph is pretty unnerving, as the car has a really bad tendency to wander and feels very uncontrolled, kind of like it's floating.

I replaced everything with the exception of the drag link, strut rods/bushings, coil springs, and ps slave cylinder, as those parts all appeared pretty new or in relatively good condition by the look of them, and the place I bought it from put a new steering box on it before I bought it. I also did the shelby drop, and of course, got the car aligned. It's certainly better then it was before I replaced everything, but it's still not as good as I would like.

I've had several old cars in my day, so I'm well aware of how they handle versus a new car, but I don't remember my other mustangs being quite as sloppy. Heck, maybe they did and I just didn't have a good frame of reference back then.

Whatever the case, what else can I do to further improve things, short of going R&P? I'm planning on a 408 build in the next year, so my goal has been to get the car shored up so it can safely handle the additional power. It's not going to be a track car or anything, but I'd like it to feel stable running down the highway or between stop lights. Any suggestions?
 

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When you got the alignment done was it to stock specs or drop specs?
 

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Same question as Tx above, they should have supplied you with a paper stating the specs they set the car to, post the specs and you'll get some useful input.
Jon
 

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Discussion Starter #4
I gave then the specs opentracker gave me, but it looks like they probably used what was in the computer instead. Here's what i've got on the print out:

Front
Camber: left .78, right .76
Caster: left .36, right .16
Toe: left .19, right .17

Cross camber: .02
Cross caster: .20
Total toe: .35

Rear
Camber: left -.19, right -.40
Toe: left -.19, -.14
Toe angle: -.33
Thrust angle: -.02
 

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When you say "sloppy", I think of "play" in the steering wheel. Is there?
 

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Caster: left .36, right .16? You have got to be kidding me. 3 degrees minimum, 3.5 is better.

That is a HUGE part of your problem.

If you want to make the best bolt on improvement you can get a set of Konis. You will be shocked at the difference.
 

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Caster: left .36, right .16? You have got to be kidding me. 3 degrees minimum, 3.5 is better.
I agree, his alignment sucks. Here's the book spec. He's not even close:

 

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Discussion Starter #8
Thanks guys, I knew something didn't feel right. 22, that's the actual sheet I gave them, I printed it off another forum post where you had posted that. I told them to use the shelby specs, those are the same as what opentracker gave me, but obviously they didn't. I should have looked over the specs when I picked it up, my mistake.

I'll get it re-aligned, then re-evaluate what I need to do from there.
 

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So I replaced all of the suspension, steering, and power steering components, but the handling still leaves quite a bit to be desired. Getting up over 65 mph is pretty unnerving, as the car has a really bad tendency to wander and feels very uncontrolled, kind of like it's floating.

I replaced everything with the exception of the drag link, strut rods/bushings, coil springs, and ps slave cylinder, as those parts all appeared pretty new or in relatively good condition by the look of them, and the place I bought it from put a new steering box on it before I bought it. I also did the shelby drop, and of course, got the car aligned. It's certainly better then it was before I replaced everything, but it's still not as good as I would like.

Any suggestions?
I guess you replaced the sway bar with at least a 1" sway bar too?
 

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Stock alignment spec's are for bias ply tires. They have different contact patch tendices that radials. Stock alignment specs with modern tires does feel dangerous. You may have a tough time finding a shop that wants to work on an old Mustang and secondly finding a place that will set to your spec's. The shop has liabilty to think about.
Buy an alignment tool from Speedway motors, make some grease plates and do it yourself. Tool cost $100 and you can set it up exactly how you want, any time you want. Not difficult at all.

I would go for thr Shelby R modle spec's from the table posted above. If street only, I would go with less camber (as in zero)for better tire wear, but you need the caster for more stability.
 

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Just for example:
Caster: left .36, right .16
Are they kidding? I could understand if you read this off of a "before" printout, that's the kind of figures you's get by sheer guesswork when installing a new front end.
 

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Just a point of clarification. It is my understanding negative caster is where the top of the spindle is slanted toward the rear of the car, positive caster is where the spindle is slanted toward the front.

positive caster makes the car easier to turn at parking lot speed

negative caster makes the car feel more stable at higher speed

Correct??
 

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Discussion Starter #14
I guess you replaced the sway bar with at least a 1" sway bar too?
Not yet. It's on my list, along with some tin man sfc's.

I called the shop and they said they'd take a look at it next week, and readjust it. Hopefully they'll get it right. If not, I may have to look into aligning it myself.
 

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Just a point of clarification. It is my understanding negative caster is where the top of the spindle is slanted toward the rear of the car, positive caster is where the spindle is slanted toward the front.

positive caster makes the car easier to turn at parking lot speed

negative caster makes the car feel more stable at higher speed

Correct??
Other way around. Positive caster is with the upper ball joint farther back than the lower.

Neg. camber = top of tire in . . Pos. camber = top of tire out
 

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Discussion Starter #18
X2 on the improved strut rods. Spend the $ before you get your next alignment
That's pretty steep for a set of those, how much of an improvement are we talking here, and what exactly is the benefit?
 

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An optimal suspension design is called an SLA setup. Short Arm/Long Arm. Known in street parlance as a double wishbone.
The mustang suspension is a low buck implementation that approaches just that. The deficiency is that the lower arm has a single mount point.

In order to control front to back deflection associated with a single mount point, and still allow the movement of the lower arm in the intended plane, the designers tacked on a strut rod mounted between the lower arm and the chassis on giant rubber doughnut bushings. For the period this served the purpose.

Today - not so much. The S/T or TCP and others replace the rubber bushing with either a ball joint or a heim joint that functions to keep the movement of the lower arm perfectly within the design plane.

For the driver this translates into significantly more predictable behaviour as the car traverses uneven surfaces, hard braking conditions and high g-force turns during which you encounter a disturbance (aka - A Whop-tee-doo).

Today - as you drive your mustang over uneven surfaces you may note that it darts around and doesn't feel 'stable'. You think - heck - I have all new parts in this thing!.

The reality is that todays tires are wider and stickier and FAR more competent than in the 60's and as a result - the better tires exert significantly more influence over the lowly doughnut bushing design - allowing for unwanted vectors of deflection/travel in the lower arm ultimately evidenced by the symptoms previously described.

So - yes they are a couple of hundred bucks. But they may be the best couple of hundred bucks you spend. :)
 

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Discussion Starter #20
Wow, thanks for the detailed explanation, that makes a lot of sense. I will definitely put those on my short list of upgrades. I'd go ahead and get them now, but I just dropped a chunk of change on a set of koni's, so I'll have to wait until next month to get them.
 
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