Alignment drift?

[302 coupe]

interesting read Krash. There must alot of variance amongst the granada spindles and 65-66 chassis's. My car is setup for street/drag, lowered 1.5", no shelby drop, my own personal backyard alignment, and I've never had any bumpsteer problems. Also, on launch, the front end lifts a good 5-6 inches and settles back as soon as I ease up on the throttle, I can't feel any binding. All stock front end except for the springs and shocks and lack of sway bar. I have the feeling that geometry varies widely from car to car, and becomes even more unpredictable when aftermarket parts get used. I'm considering switching from the granada brakes and spindles to a set of lightweight wilwoods or aerospace discs, along with a switch back to original spindles. If there is a noted change in feel, I will definately let the members here know.

 

[krash kendall]

Yeah, I read that about a year ago when the author posted it here and it made me cautious about spending a whole whack of time finding Granada parts and coming up with a laundry list of hose, fittings, M/Cs, prop valves, tie rod ends, etc. only to find out the already poor geometry match is incompatible with some variance in my 40 year old +/- 1/4" tolerance car.

I'm seriously looking at scarebirds plates (I know his name has come up a lot this week), he is within 1.5 hours from me, and watching to see what degins comes up with for '65-'66.

I'm hope Historic isn't reading this....

 

[302 coupe]

by the sounds of things, Historic is pleased with the granada stuff too. Just odd that some people have severe problems with it while others don't.

 

[krash kendall]

I know, but he doesn't have much positive to say about the other two I mentioned because they weren't built by Ford 35+ years ago.

 

[302 coupe]

true. Regardless, if he were having bumpsteer issues he would have mentioned it. He is one of the very few people here that actually uses one of these old cars in competition, and if there were an advantage to be had by using stock 65-66 spindles over the granada spindles, he probably would have switched by now. There are a lot of people using granada discs (probably more than any other disc swap) and the vast majority of them seem to have no problems. Basically, what I'm saying is to not just automatically assume the spindle is the cause of the original posters problem. It could be alot of things, maybe a cracked shock tower, maybe a worn steering box, it could be a multitude of things when dealing with a 40 year old unibody car, even when it has 'new' parts that were probably made in china. The spindles alone will not cause a tire wear issue, or create constantly changing toe settings. Spindles can cause bumpsteer issues, but whats causing the tire wear and toe problems? It sounds as if the original poster doesn't know what the actual toe setting is, he did however state that it changes 1/2" when the car is jacked up (don't know how it was measured though). If the toe is properly set with the car at normal ride height, his tire wear issues can only be attributed to camber settings, or some way odd caster issue. If the nose of the car raises on accleration and won't come back down to normal, he has a binding issue somewhere, which could possibly be traced to a toe problem, but he has only a 1/2" of toe change when the car is jacked up. Now, when you consider that toe should be set at -1/8"(give or take), and he has 1/2" of positive toe change, that only gives +3/8" toe, hardly enough to cause the suspension to bind.

 

[krash kendall]

I agree with you about how happy most people are with the swap and also that a varety of problems could be the route cause. His front could have welded at 4:55 PM on Dec. 24th for example. It definitely would have been helpfull if he had driven the car prior to it being torn down.

 

[302 coupe]

yup.

 

[BobV]

The spindles alone will not cause a tire wear issue, or create constantly changing toe settings. Spindles can cause bumpsteer issues, but whats causing the tire wear and toe problems?

Bumpsteer IS defined as "toe change during vertical suspension travel". The Granada/Maverick spindle's steering arm is different than a 65/66 arm - it locates the tie rod pivot approx 1/2" further "in", 1/2" "up", and 3/8" closer to the spindle pin. The tie rod assembly now travels in a different arc, with a different length than the lower control arm. The additional 1/2" of toe that the original poster measured means that he's running 5/8" toe-IN at suspension lift. I'd bet he also see at least 1/4" toe-OUT under hard braking , for nearly an inch of toe change. That will wear tires.

The reason others "don't have bumpsteer" is that they've never measured it. These cars (even stock) have bumpsteer. The spindles make it worse. Yes, there is some variance car-to-car, depending on alignment specs, control arms, suspension modifications, etc. A car with lots of suspension travel, low ride height, lightweight front end, and STICKY low-profile (225+ section, 45 aspect) tires will magnify the bumpsteer - producing the problems mine first had. (Yes, that's my website you were reading). I'm always leary on anyone who claims "zero bumpsteer" - there's no such animal... You might get "minimal" (a few thou / inch), but you won't have zero throughout the full range.

Historic "gets away with it" because of stiff springs and limited suspension travel - racetracks don't require the amount of travel that a street car typically needs. He's never measured his bumpsteer, nor driven a bumpsteer-corrected car. He's adjusted his driving style to rotate the rear of the car, instead of using front grip. Works on a racetrack, but can get you killed on the street...

As far as the original poster's problem... I believe he stated that he had driven the car 15k miles? And the problem recently worsened, or has it always been there? (unclear to me based on what I read). If it's always been there, I'd suspect the spindles. If it's recent - something has changed - stickier tires? Changed alignment? Most people with near-stock setups and later spindles have some success with running as much + caster as possible, combined with a ZERO toe setting - these two things will help mask the bumpsteer. Might be a lot easier to try those specs than changing out the spindles/brakes.

 

[302 coupe]

Hi Bob, good to see you post again, I haven't seen you around here in a while.

I'm aware of what bumpsteer is. Under normal driving you're not continually riding around with the suspension compressed or extended. If toe is set with the car at normal ride height, his noticeable tire wear will not be caused by bumpsteer. Tire wear would be a result of continuous operation, not the occasional split second of toe out caused by hitting a bump, or the 10-15 seconds you may spend coming to a stop from 60 mph. Considering the original posters car is not lowered, nor does it have low profile tires, bumpsteer due to granada/maverick spindles will most definately be minimized. However, a bumpsteer kit might be worth looking into. If I were him, I would thoroughly check each and every other component first before buying the bumpsteer kit or considering replacing the spindles/brake system. I think it probably just needs a GOOD alignment, which it doesn't seem to have had yet.

 

[krash kendall]

Right here Bob,

I didn't drive it before it was torn down so I don't have any reference to
the stock handling characteristics. I'm not the primary driver either so I
only get reports from the wife and my occasional run around. She had no
idea the growl from that wheel bearing was a bad thing.

I didn't realize that was your site. I think another member (gt350clone?) linked it awhile back and I thought it was their's because of the screen name.

Just to clear things up 302coupe, I wasn't saying that the spindles were the absolute problem, it is just that his symptoms made me immediately think of Bob's site. The mention of the other two systems compared with my opinion of the sundry of different parts needed for the Granada swap was purely to illustrate why I'm still not sold on doing it for my car based on these unexplained, and yes, uncommon irregularities that pop-up with the Granada swap. It was slightly off topic.

 

[krash kendall]

Still, under normal driving you're not continually riding around with the suspension compressed or extended.

I think he said it remained high after stepping on it and low after hitting the brakes. Spring perch or UCA cross-shaft could be binding.

EDIT: Added word "perch" after spring.

 

[BobV]

Right here Bob,

I didn't realize that was your site. I think another member (gt350clone?) linked it awhile back and I thought it was their's because of the screen name.

I post here as BobV - used to be GT350Clone everywhere, but that screenname got messed up in a server crash, and I just set up a new user instead of trying to work it out....

Here's what's confusing me:

all new suspension parts, less than 15k miles, still check out tight and good condition

Does that mean "new" , or 15k miles?

Toe change can kill a set of tires - I can tell you that even after swapping back to 65/66 spindles, I had an inch of toe change (aka bumpsteer), due to the revised GW geometry. I completely TRASHED a set of front tires in a couple thousand miles. Between toe and camber changes, the tires wore both the inside and outside edges - braking cause toe-out and neg camber, wearing the insides, and acceleration / turning caused toe-in and positive camber, wearing the outsides...

I had absolutely no "bind", other than the tires binding/scrubbing the pavement. That's what held the car "up".

After the Baer bumpsteer kit, I had <.125 change in 6 inches of travel, and <.030 change in the 3" "sweet spot" of travel. The last set of tires had 20k + miles, including track time, and were wearing perfect!

 

[Cdaniel]

Ok original poster here again, I'll try to clear up some confusion.
1. The car does not have a "lift and stay" problem like the one in the linked story. The lifting is slight when accelerating and returns to normal when you back off the throttle. The tires squealing and darting when accelerating was a recent development discovered while test driving after replacing the wheel bearing. This condition may have been present before and I didn't notice during my brief drives in the car.

2. All front suspension parts save the springs were new less than 15k miles ago. And I describe them as "tight" as opposed to loose. Not binding. And yes, they are after market made who knows where. But the still seem to be holding up fine.

3. The steering box was rebuilt by a reputable shop at the same time and still works properly. I do have a slight amount of play between the box and it's connection to the Flaming River tilt column. Very slight.

4. The 1/2" toe in change I observed was when the car was lifted well over what I believe would be a normal driving condition unless you hit a big bump. I was just trying to see which direction the tires were going so I could add some toe adjustment in the other direction. My crude measurements were made with a tape a given distance from the floor at the edge of a tread groove.

5. The unibody structure is sound. No shock tower cracks. The guy who did the body/paint work was impressed buy it's lack of rust and collision damage. Although the core support has been replaced sometime in it's life. I'm thinking a shock tower support might be a good idea to help it maintain an alignment.

I'm not confident this thing has ever really had decent alignment. The last one seemed to be fine until I did my test drive mentioned above. I had my wife take it back to the same shop to get it checked but the old timer that did it wasn't there. They bailed out on me saying I had play in the steering box. BS! The box is fine, I think the youngster there didn't know what to do with it. They didn't even put the alignment heads on the wheels. Sent her home and called me to say the box is bad. I plan to return personally tomorrow and at least get it checked (if the old guy is there).

Just for history's sake here are the alignment specs from the past. Needless to say these numbers are only as good as the last rack calibration and the set up by the garage monkey.

1st
left camber -.10 deg
right camber -.10 deg

left caster -2.00 deg
right caster -1.70 deg

left toe +.05"
right toe +.06"

2nd (after discovering and replacing the bad strut rod bushings and noticing inner tire edge wear/scuffing)

Before
left camber +.20 deg
right camber -.80 deg

left caster -2.10 deg
right caster -1.50 deg

left toe -.32"
right toe -.15"

After
left camber -.00 deg
right camber -.00 deg

left caster -1.90 deg
right caster -1.00 deg

left toe +.03"
right toe +.04"

3rd (still noticing inner tire edge wear/scuffing)

Before
left camber -.40 deg
right camber .40 deg

left caster -2.60 deg
right caster -1.60 deg

left toe -.37"
right toe -.13"

After
left camber -.30 deg
right camber .30 deg

left caster -2.60 deg
right caster -1.60 deg

left toe .06 deg
right toe .22 deg

the car handled better and appeared to have better tire wear after this.


Shop manual specs
camber -.50 to +1.00 deg (+.25 desired)

caster -1.00 to +1.00 deg (0 desired)

toe .125 to .375" (.25" desired)

So at this point I've dialed back the toe in 1/4 turn on each wheel after a few trial and error runs to eliminate the squeal when accelerating. Not sure of the actual measurement without the proper tools. The tires have a negative cambered stance now where before they didn't. I'm going to start hunting for a shop that can provide a more comprehensive alignment instead of the flat rate your outta here approach. If the diagnosis still points to tie rod issues I'll see about getting some adjustable ones.