Alignment Question (Car Wandering)

Steve Burton · 10-02-2012, 07:52 AM

I have seen many discussions around the use of the 60's specs being out to lunch and a newer spec more in ture with today's tires, and better handling.

I have a 68 vert, with radial tires, and have just replaced the front steeting linkage, and braked, so I put it in for an alignment. I also installed a Borgeson integrated power steering box.

The car was aligned to the original specs, and now the car wanders at higher speed, and on rough roads.

Here is what the car is aligned to now:

Caster: -0.59 Left -0.50 Right

Camber: 0.18 Left -0.16 Right

Toe: 0.10 Left 0.10 Right

Any advice on what they should be?

Car is stock steering with front disk brakes, and borgeson integrated power steering box. I know Borgeson recommends 3-4 degrees for Caster, but I am not sure about the other settings.

Also, the passengers side is adjusted all the way in, so I have to do something to address that also. The car must have been in an accident at some point.

Thanks,

txtrailerdaddy1 · 10-02-2012, 08:06 AM

If you did the borgeson, it comes with a note telling you to change to positive camber I believe. I can't recall.... but it definitely is not original specs. I think that was to help with returning the wheel to straight after a turn though...... It's too early to remember all the details.

kenash · 10-02-2012, 08:10 AM

Hi,
My first thoughts are to increase the positive caster to near + 2'ish. I'm running radials, my specs are .05 camber (neg), +2 caster (slight diff left to right for road crown), 1/16 toe in.Mine's a '65 with a 1" UCA drop. But, I'd still recommend to "plus" the caster.
I have great road stability.
Good luck!

txtrailerdaddy1 · 10-02-2012, 08:35 AM

That's it, it was caster. My borgeson came with an Orange card that said they recommended going to positive caster.... There was a number on it, can't recall what it was, but I thought it was 5.... now I gotta go dig that card up.

kenash · 10-02-2012, 10:02 AM

Quote:

Originally Posted by txtrailerdaddy1

That's it, it was caster. My borgeson came with an Orange card that said they recommended going to positive caster.... There was a number on it, can't recall what it was, but I thought it was 5.... now I gotta go dig that card up.

Hi,,
With your power steering, you could probably go +5, or so. For us guys with manual steering, the more caster the more low speed steering effort. It's a trade off, of sorts.
Good Luck!

MrFreeze · 10-02-2012, 11:22 AM

You absolutely need all the positive caster you can get. With zero or negative caster your car will wander. What size wheels/tires are you running?

MrFreeze

jmn444 · 10-02-2012, 11:49 AM

I have over 3 degrees positive caster with the borgeson, and considering looking to get offset upper control arms to gain even more... I cannot beleive the difference in handling on the track going from approximately zero caster to over 3 degrees... it is truly night and day. The car is VERY stable all around and no wandering at all... I feel like I've pulled the lower arm as far forward as I'm comfortable with at this point though.

jmn444 · 10-02-2012, 11:52 AM

I would personally put more negative camber in too, but for normal street driving that won't matter a whole lot.

Steve Burton · 10-02-2012, 01:14 PM

Quote:

Originally Posted by MrFreeze

You absolutely need all the positive caster you can get. With zero or negative caster your car will wander. What size wheels/tires are you running?

MrFreeze

I am running P215/50/R17....

MrFreeze · 10-02-2012, 04:16 PM

It appears to me (no scientific evidence, just my opinion) that lower profile tires make this problem worse. So again I say, get all the positive caster you can. 5 or even 6 degrees if you can get it. I think your '68 will have adjustable strut rods, so I assume lower control arm bind will be a limiting factor, but you can also have the alignment guy add some shims to the forward upper arm bolt on each side to get more caster after you are out of adjustment. As jmn444 says, the difference is HUGE.

Good luck,
MrFreeze

Tims65 · 10-02-2012, 08:07 PM

My guess, is it's going to be due to the alignment. If you took it to a shop and had them do a stock alignment, the car will feel very twitchy and want to wonder a lot at highway speeds. If this sounds like what you are experiencing, go back and have the alignment set to the performance specifications:

The original stock alignment setting for '64 - '66 Mustangs are:
Caster: -0.5*
Camber: -0.5*
Toe-In: 9/32"

The Performance alignment settings for the "Shelby" drop are:
Caster: +1.5° to +2.5°
Camber: 0 to -.5°
Toe: 1/8"

The biggest difference being in the Caster setting. A positive Caster setting will help the car to track straighter and return to center more quickly after a corner. The easiest way to describe it would be to think of a bicycle and angle of the front wheel fork. If the fork that connects the handle bars to the front wheel were to be straight up and down (0 degrees Caster) you would constantly need to steer to keep the bike going in a straight line. Now if the front fork were installed at an angle (think chopper - Positive Caster), you could take your hands off of the handle bars and the bike would continue to track in a straight line.

Huskinhano · 10-02-2012, 11:25 PM

Yup, more caster. I just installed Street or Track adjustable UCA as well as their adjustable strut rods that use a rod end for smooth, free travel. I installed these parts even though it was more money then I wanted to spend at the moment but I want a nice driving car that I can easily add caster.

Steve Burton · 10-04-2012, 05:40 AM

Quote:

Originally Posted by Huskinhano

Yup, more caster. I just installed Street or Track adjustable UCA as well as their adjustable strut rods that use a rod end for smooth, free travel. I installed these parts even though it was more money then I wanted to spend at the moment but I want a nice driving car that I can easily add caster.

Can you confirm for me that there was more adjustment than a stock strut rod on the Street and Rod adjustable strut rods? On one side I am at original specs, and I am adjusted all the way in.

Also, any idea how many turns equals a degree on a strut rod?

Steve Burton · 11-13-2012, 07:17 AM

Anyone know the maximun caster on stock strut rods?

can you achieve more caster with an after market adjustable line TCP adjustable strud rods?

I don't want to spend the money if I don't have to.

cmefly · 11-13-2012, 07:48 AM

Quote:

Originally Posted by Steve Burton

Anyone know the maximun caster on stock strut rods?

can you achieve more caster with an after market adjustable line TCP adjustable strud rods?

I don't want to spend the money if I don't have to.

The limiting factor is the bind you will put on the stock lower control arm bushing when you pull the lower arm forward to achieve max caster. If you are trying to max out the caster I would look into a lower arm that has a heim joint like the lower arms that OPENTRACKER sells. I am not sure how much more caster you can get from the aftermarket strut rods. I have a set of STREET OR TRACK on my 65 and they are very well built.