Your donations help keep this valuable resource free and growing. Thank you.
|
Pacer Spindles for Racers? |
Post Reply | Page 123 6> |
Author | |
farna
Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19612 |
Post Options
Thanks(0)
Posted: Nov/09/2019 at 8:27am |
You can fit a later model AMC rotor or hub on the 71-74 spindle. All AMCs EXCEPT the 75-78 models use the SAME spindle length and bearings, even drum brakes models, from at least 1952-1983. The 75-78 models (regardless of car size/model) use a bigger bearing Bendix spindle. Don't know why they went that route, may have just been price from the supplier (Bendix). The rotors for those are a bit pricey, so I'm pretty sure they don't cross reference to any other makes. You can use a hat type rotor with a drum brake hub, just remove the drum. That's what Scarebird does in their kits -- or you can cut the worn rotor off a hub/rotor and use that as the hub (turned off on a lathe or brake lathe). You just have to get the right depth hat rotor, or shim the caliper bracket. You may be able to find a Wilwood or other aftermarket hat rotor with the correct offset to replace a K-H rotor.
|
|
Frank Swygert
|
|
Brad
Supporter of TheAMCForum Joined: Aug/07/2016 Location: Canada Status: Offline Points: 431 |
Post Options
Thanks(0)
|
Just a thought.... with the insane prices for 71-74 Javelin rotors it might be a plan to use the Argo spindles as they use a pinto pin and that opens up lots of options for cheaper and more available rotors going forward.....
|
|
Brad
Supporter of TheAMCForum Joined: Aug/07/2016 Location: Canada Status: Offline Points: 431 |
Post Options
Thanks(0)
|
Here is some pictures of all 3 steering arms bolted together for comparison . 71-74 Javelin, ARGO and stock Pacer. The ARGO arm is in the middle, its the same as the Pacer except there is no left/right as the tie-rod boss is straight and has a 5/8" holes as previously mentioned. And the top boss is thicker, same as the Javelin boss. Hope this helps someone out down the road!
|
|
Lucas660
AMC Addicted Joined: Apr/16/2012 Location: Vic, Australia Status: Offline Points: 1344 |
Post Options
Thanks(0)
|
Thanks for all the advice here. The Australian Fords are all rear steer, and all the Holdens as well except for this later model, the model after is also front steer but electric power steer.
Since this is a right hand drive application I do not have a huge variety of racks to choose from. Thanks for the offer to send a arm, but it is no drama for me to make something if required. I think with all of the information offered here I have come up with a solution and will most likely finish my build thread in the lounge area of the forum. |
|
farna
Supporter of TheAMCForum Moderator Lost Dealership Project Joined: Jul/08/2007 Location: South Carolina Status: Offline Points: 19612 |
Post Options
Thanks(0)
|
I suspect the Argo Pacer arms were made slightly different from the factory Pacer arms to make them work better in a dirt track chassis. My guess is they use the Pacer (or rather AMC) steering knuckle and spindle only, mainly because they are two piece and can be adjusted with spacers, and the slightly different arm fixes the steering in the dirt track chassis being used. As you can see, moving the rack back doesn't make a lot of difference. In actual driving you wouldn't notice the difference shown. Lucas, what makes the tires turn at different angles is the position of the outer tie-rod end. Both the angle from the ball joint and the length. Again, the easiest way to find the position is to make a temporary arm with moveable ends. I wonder what it would cost to just send you one of the arms I made (and not suing any more)? The other option is to get standard Pacer arms since they work "good enough" on the 63-66 big car (and Javelins). You should be able to find someone in the US to send you some. Other than that, position and width of the rack is critical. The tie-rods can be at a slight angle and not have enough of an effect to be noticeable. The inner pivot points MUST be very near the pivots points of the lower arms though. I think you can be as much as 1/4" in or out (on both sides) and have it work fine. The illustrations 304-dude posted indicate you can be offset a bit without a lot of change, but the inner tie-rod pivots STILL need to be the width of the distance between the lower arms pivot points. Ford racks are front steer and come in three different widths -- Mustang II/Pinto is the narrowest, Ford Contour (and I think later Mustangs) the middle, and the 80s-90s T-bird the widest. Come to think of it, the racks might be close to the same width, the tie-rods ends are short to long like that. It's so popular that you can get extensions that screw between the tie-rod end and rack to make it wider. Can be used on both or one side. Use on one side to offset the rack and still have the pivots in the right places. It looks like the GM rack might be a bit too wide from the photos in your rack install thread. The outer tie-rod pivot points look to be further out than the lower control arm pivots. That will cause some bump steer issues once the geometry is corrected, but if only a little longer it may not cause enough to be noticeable. Could just be the angle of the photos though.
Edited by farna - Nov/07/2019 at 6:45am |
|
Frank Swygert
|
|
304-dude
AMC Addicted Joined: Sep/29/2008 Location: Central Illinoi Status: Offline Points: 9081 |
Post Options
Thanks(0)
|
Another note about how far to move a rack rearward...
Though the easiest way to determine how fare back can be done at full turn lock. The tie rods should be parallel to the lower ball joints axis. But never exceed beyond the axis line by over rotation. Though many street cars have forward racks, and work out fairly well considering. What really helps is a custom steering arm or spindle to allow Ackerman to work. Here are a couple of diagrams that I based my rack install upon. There is a distance shown of 1.25", between arm end hole centerline and ball joint centerline. Setting too far back will put too much angle into the rack pivot points. Thus the need to verify by checking parallelism locked at full turn. Edited by 304-dude - Nov/07/2019 at 6:15am |
|
71 Javelin SST body
390 69 crank, 70 block & heads NASCAR SB2 rods & pistons 78 Jeep TH400 w/ 2.76 Low 50/50 Ford-AMC Suspension 79 F150 rear & 8.8 axles Ford Racing 3.25 gears & 9" /w Detroit locker |
|
Brad
Supporter of TheAMCForum Joined: Aug/07/2016 Location: Canada Status: Offline Points: 431 |
Post Options
Thanks(0)
|
I missed that post, Thanks! Nice job on the mounting crossmember! Looks easy enough to slot holes/shim rack for adjustments. You could use washers tack welded in position when you get it where you want it so you don't lose your settings if you ever need to remove it again down the road. I noticed shims on the frame rails, is it centered in the chassis? I found this , maybe helpful for the pictures? https://pacertruck.wordpress.com/category/pacer-pickup/
|
|
Lucas660
AMC Addicted Joined: Apr/16/2012 Location: Vic, Australia Status: Offline Points: 1344 |
Post Options
Thanks(1)
|
Here is the build thread:
http://theamcforum.com/forum/rack-and-pinion-for-right-hand-drive-64-classic_topic101925.html The rack is from a VE Holden Commodore, right hand drive as I have an Australian delivered Rambler. Internationally, the VE Commodore was badge engineered as the Chev Lumina, Chev Omega and Pontiac G8. It has 6 inches of travel and 2 1/2 turns lock to lock. I thought I had measured everything properly when I pulled the rack from a wreck, but obviously not. It does drive great with the original steering arms but I have the same problem as Frank, not easy to park. I will experiment with moving the rack as far rearward as possible, and taking it from there. The input shaft to the rack will end up in the engine mount but I can work around that with universal joints if everything else checks out OK. Considering that I live in a rural area and most of my driving is at high speed I am not concerned with a small amount of tyre scrub during low speed maneuvers but my measurements the other day were alarming. Hoping to get this project finished in the next couple of weeks as I have to modify a Isuzu Ute(pickup truck) for a 4000 km outback bash that raises money for charity. |
|
Mopar_guy
Supporter of TheAMCForum Joined: Jun/07/2009 Location: Ohio Status: Offline Points: 4806 |
Post Options
Thanks(1)
|
Not exactly on topic but I pulled the wheels off of my car last night and I was pleasantly surprised to see the front tires look almost as good as the day I put them on. After 8k miles on them, there's no cupping, or uneven wear at all and considering how flat and wide the tires are, that tells me the front end geometry is darn near perfect on that Fatman IFS. I sure as heck couldn't get that with the stock suspension.
|
|
"Hemilina" My 1973, 5.7 Hemi swapped Javelin |
|
Brad
Supporter of TheAMCForum Joined: Aug/07/2016 Location: Canada Status: Offline Points: 431 |
Post Options
Thanks(0)
|
The wheel base should be taken into consideration when figuring out the desired Ackerman angles. I suspect you will need to move your rack to get what your after? What rack are you using? I ask as shorter steering arms will in effect speed up the steering possibly restoring the turning radius ? In a lot of cases with street rods the most common rack is the mustang and if you have steering arms that are too long, turning radius will suffer. Every car is different in regards to packaging and some time compromises need to be made. Oil pans, chassis, too small of rims and offsets, sway bars, etc can be " in the way" I'm hoping the AMC engineers did a good job when they designed the Pacer steering arms.
My plan is to block the car at ride height with the front springs removed and figure out where the rack "needs" to be,I check using 3" of suspension upward travel. I have turning plates, caster /camber gauge and a bump steer gauge which really helps but they are not cheap. I was involved with circle track racing for 25 years, that's why I have some of these tools. I did this with my 70 Challenger and used combinations of "stock" parts from other Chrysler cars till I optimized the geometry . I used C-Body spindles, A-Body lower control arms etc.. Only non-stock parts used were the Howe quick bump kit and aftermarket upper control arms. It took many hours of trial and error till I was happy. Most of the time was spent waiting on parts to arrive, it took months finding the original parts to experiment with, and a lot of them ended up in the corner or on a shelf , likely never to be used again. It's never perfect there are always compromises , but my Challenger handles 10x better now than it did in stock form. My Challenger in stock form was by far the worst handling and braking car I have ever owned. You have to remember these cars were likely designed for bias-ply tires, never had enough adjustment for caster for today's modern radials. That and the fact that handling/braking was not exactly high on the list of " must haves" as compared to today's cars. If you use "factory alignment specs" to align the front end of these old cars with modern radials they will handle horribly! Or take a new driver used to modern cars then put them behind the wheel of a " classic" . They likely will need a change of underwear in short order. Drawing it out on paper or a computer screen is great and all but there is no substitute for the real car as even the smallest mistake on measurements can really effect the outcome. Tolerances in things between different manufacturers of components, such as tierods , ball joints, factory frame tolerances , accumulative tolerances, etc... all factor in. Might " look good on paper" but when implemented on the actual car being used often fall short of the desired outcome. IMO there is no substitute for "rolling up your sleeves and getting dirty" on the actual car. Just my 2 cents, hope it helps.
Edited by Brad - Nov/06/2019 at 7:39pm |
|
Post Reply | Page 123 6> |
Tweet
|
Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |