Installing b body spindles. What are the optimum alignment specs?

[UNGN]

Since I always were the outside edge blocks away on the front tires first, -1 degree of camber actually reduces tire wear for me vs. 0 degrees. It depends a lot on the type of driving you do. If most of your tire wear comes from high mileage, zero to -1/2 might be better. If most of your tire wear comes from highway off ramps -1 to -2 degrees might be better. With todays assymetrical tread designs, negative camber will help save the outer tread blocks, because once they are gone, the tires are junk.

Did your arms come with "Offset" shafts? If so, instead of more or less shims, the shafts can be rotated 180 degrees to move the upper balljoint in or out and then shim from there. I wouldn't think you would need much more than an inch of shims and even less with offset shafts.

 

[GNVAIR]

Being that I do mostly highway driving, then I agree that maybe I should dial in more camber.
As for the shafts. They are whatever Global West supplies with their arms. I was not given an option when I purchased them back in December. I am not even sure how to tell the difference.
Any ideas?

 

[UNGN]

Offset shafts aren't symmetrical. The centerline of the shaft isn't the same as the centerline of the uppercontrol arm bushing bolts. Its offset about 1/2 an inch. So when you rotate it 180 degrees, the offset face moves from the inside of the arm to the outside. Offset arms would say something like "wheel side" on one side of them.

If you don't have ofset arms, no biggy. You just have to use a few more shims to achieve more negative camber. If you want to stay close to zero, you shouldn't need too many.

 

[BJM]

Do any of you get the story," You shouldn't change the settings from the factory values. It can be dangerous". I get that with everything I try, springs, shocks, tire sizes. Sheesh.

 

[GNVAIR]

Well, I completed the upgrade today and just came back from an alignment session at a friends shop. I got the camber right at -1.0
and the toe at -.05. It took a lot of shims. Over 1 inch worth on the passenger side; so obviously, Global West doesnt include the offset shafts that they should. Here is my dilema; the caster was stuck at 6.5° on the passenger side and 4.5° on the driver side. We couldnt figure out how to get the caster back OR to at least minimize it on the passenger side. It now has a bad pull to the left and the steering wheel is off that way as well. I check the bushing alignment on the lower control arms and there really is no room to move the control arm back to decrease the caster. So, my question is; What do I do now. The car cant really be driven safely like this. As such I am really at the mercy of those who have performed this swap before. Any suggestions would be greatly appreciated. TIA.

 

[UNGN]

Take some shims out of the back bolt and move them to the front bolt to rotate the passenger side upper arm to get less caster. Do the opposite on the driver side and shoot for a equal caster of 5.5 degrees or so. I don't think the two bolts require equal shim amounts.

 

[GNVAIR]

Ok, I got the alignment done. Caster is set at 4.9° positive, camber is at -.9 and the toe is approx -1/16"
It handles pretty darn well. The brakes are wicked! The ride with the Del Alums and stiffer springs is actually better than stock.
Here is my set up:
Global West UCA's with Del Alum on left and brass on right
Stock LCA's with Del Alum, new ball joints
Bilstein shocks
b body spindles
Raybestos 5994 12" rotors with all new bearings and seals
Moog tie rods, centerlink, idler arm
Hotchkiss tie rod sleeves
Stock front sway bar with Energy Suspension sway bar end links and new stock rubber mounting bushings
Moog 5660 coil springs
Rebuilt stock b body calipers
Performance Friction brake pads
New Bendix b body master cylinder with a g body reservoir swapped on to clear the hood.
New replacement front b body brake hoses (unti my Russell hoses arrive)
I am using 4 GTA rims (rears mounted on the front and the fronts mounted on the rear)
Tires are P245/50ZR16(front) P255/50ZR16(rear) Kumho ECSTA Supra 712's
I still have to install my rear shocks, box the rear LCA's and install the new 1LE LCA bushings I have.
My main problem now is the back end is very loose compared to the front. I know the shocks wont help the body roll in the rear. What can I do to eliminate it? A bigger sway bar? Air bags? Stiffer coils?

 

[Ormand]

Caster

Caster is adjusted at the top, not at the bottom. By using more shims in back than in front, the top of the spindle is tilted backwards. You may end up with too many shims in front if you don't have the offset shaft. Also, the steering wheel will be off center if you don't have both tie rods the same length. Shorten one, lengthen the other, so toe-in remains constant, but you get the steering wheel centered.

 

[GNVAIR]

Ormand......I dont think you read the last post. We solved the alignment issue AND yes, I do understand now how caster is adjusted.

 

[UNGN]

Man, that sounds great. I just have to zip my motor back together and get mine back on the road.

 

[GNVAIR]

UNGN.......I will keep you guys posted how I progress. I have a couple of local g body guys that are into autocrossing, so this with be an evolving project. I am probably going to try a thicker rear sway bar next. I also have to do the body bushings and add some more bracing. Lets keep this thread going.

 

[BJM]

Got my alignment done

Just for comparison, my front end is freshly rebuilt with all new rubber bushings, 5660 front springs, cc501 rear springs, new ball joints, outer tie rod ends, poly sway bar links on stock bar.

My car drove great before the rebuild. Simply removing, repairing, and replacing gave me:

Left Right
Caster 3.3 2.6
Camber 0.0 0.2
Toe -.5 -.7 deg

The toe I only adjusted with a measuring tape, measuring the length of the tie rod when swapping new for old. The car was twitchy and pulled left moderately while braking.

After the alignment yesterday

Left Right
Caster 2.9 2.9
Camber 0.0 0.2
Toe 0.05 0.05 deg

The guy did the best with what the car would allow. I could not get any more caster with less camber because the driver side rear bolt ran out of threads.

So that is what I could achieve with stock upper arms. The car drives straight and true so far.

BTW it seems to me that if Global West designed their arms correctly in the first place there would be no need for offset shafts.

 

[GNVAIR]

No need for the offset shafts. I had a friend that has been working in the automotive field for 15 years tag along.
He showed me where I screwed up. Technically, I could have gotten over 7 degrees of positive caster on mine with non offset shafts with the Global West arms. I can only imagine how much more would have been possible if it had offset shafts. Anyone for 9+ degrees?
As stated, I have mine down at a conservative 4.9° positive at the moment. It tracks nice and straight. The grip on the front end with the fore mentioned parts combo is unbelievable. I just have to either get higher rate springs in the back with the stock sway bar or go to the ATR bar. I am planning the later of the 2.

 

[UNGN]

Re: Got my alignment done

Originally posted by BJM
BTW it seems to me that if Global West designed their arms correctly in the first place there would be no need for offset shafts.

This is probably true, but not everyone wants -1 degree of camber. Hotchkis arms come standard with offset shafts. Offset shafts also allow positive camber on one side and negative camber on the other for circle track guys. As far as Caster goes, there seems to be a slight difference in the upper arm mounting locations on either side of the car. I don't know if any of the aftermarket arm manufactures take this into account.

 

[BJM]

If I find an appropriate longer bolt somewhere I can add more shims to the one position and pull more positive caster as well as pulling the camber negative slightly which would be ideal.

 

[AsphaltAnihil8r]

You guyz have me all worried about doing this swap,,My UPCA are on their way from Robert Adams ,I have new rotors from the LE1 ,,I just want my car to drive like it does now ,so all this talk of Caster and Camber has me worried that the Pimple face kid at the Tire shopp will not understand all this --thus having my car all srewed up .

Is there a General sweet spot that I want for Caster ,Camber and what ever else I need ?

Do I have to change my front springs??

I was just planning on measuring everything then poping the old off and installing the new ,then getting it aligned ,,but everyone is making me worried ,,everyone has a different combo of caster/camber


HELP!!!!

 

[BJM]

AsphaltAnihil8r

Don't worry too much about it. In general go with the recommendations from Robert Adams for your UPCA's. Otherwise keep camber near zero (+ or -) to minimize tire wear. Negative camber (-1 to -2) is good for cornering but hard on tires for wearing out the inside edges.

Lots of positive caster makes the car track straight down the road at some expense in steering effort. Old 50-60's cars with manual steering had -1 deg caster or more to make steering easy but as a result drove like shopping carts with the wheels acting all twitchy. Lots of caster also negates some of the need for camber too. Crank the wheel hard over to the left and get out and look at it, it leans back due to the caster angle so you get camber and caster adding together in slower turns especially when the wheel is cranked a lot.

Porsche adverts used to say a car with toe-in is a car out of control. While I don't know about that, keeping the toe near 0 or slightly in causes the wheels to run parallel since drag on tires makes them want to turn out. FWD cars need stiffer steering gear since the tires tug forward and backward, toe on those cars is probably more important.

Anybody doing alignments should know this stuff. Also I always walk in with the specs I want written down on paper and I insist on talking to the guy doing the job. Once they talk to you they understand what you want and usually try to help out or make suggestions. The guy I went to yesterday was happy to help out because I could speak his language. Most of his customers have no clue.

 

[UNGN]

Originally posted by AsphaltAnihil8r
Do I have to change my front springs??

No but stiffer front springs and new lower control arm bushings at this point will help handling.

One thing I did that I also reccomend is upgrade to the beafier B-body inner and outer tie rods and adjuster sleeves. These appear to be better designed to work with the B spindles and relocate the mounting location so they are more inline with the aftermarket bumpsteer elimination kits sold in the aftermarket. I use 1984 Caprice classic wagon as an application for the part store guy.

 

[Donald McMullin]

Thanks to everyone who has taken the time to add to this topic, the information provided has been helpful. I have been interested in real results with the B-spindle converstion.

Three questions for those who have taken the time to detail their alignment settings:

(1) Have you checked your bump-steer with the B-spindles?? I have wanted to model the B-spindle setup in comparison with the stock-spindle, but I do not have all of the measurements.

(2) Have you checked the Ackerman built into the B-spindle in comparison with the stock spindle??

(3) Is the overall steering ratio the same with the B-spindles, ie is the steering arm on the spindle the same length as stock?? If it is longer the steering wheel has to be turned more to turn the wheels the same amount as stock (plus some other things change).

Great subject.

Deep Enough

Donald McMullin

 

[GNVAIR]

To answer your questions as best as I can Donald.
#1 Yes, you will have bump steer issues albeit minimal depending on the spring rate. Mine is not bad on undulating surfaces and I have Moog 5660's. Higher rate springs would most likely lessen the effects even more so. Options could be to do what UNGN detailed by using the b body tie rods and sleeves OR utilizing a heim jointed end and spacers to correct the geometry.
#2 I let my buddy drive my car last night and he said it feels like the ackerman might be out. He isnt an expert and I am still dealing with a "loose" back end that can most likely be corrected with a heavier sway bar. Again, another negligible detail that is most likely corrected with more suspension tuning.
#3 I did not take detailed measurements of the stock spindles vs the b body units, but did lay them side by side and the length appears almost identical. No difference in the steering wheel ratio that I can tell. It feels good. The difference in the arms is in the height location and again....see answer #1