Car 70 duster stock k-frame--Adjustable upper control arms,Adjustable strut rods,.920 torsion bars,M/T SR radials all 4 corners, front 26x6x15,Rear 28x10x15 rims and tires,manual Close ratio flamming river steering box,Car is street driven, Need help with castor.camber and toe for best drive ability on the street--Thanks Guy's-----Car goes in next tuesday for alignment...
Need help with front end -Alignment
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mopardude318
Well-Known Member
4 degrees positive caster. 1/2 degree negative camber. 1/8 inch toe in. thats about what my 68 cuda has in it for a performance handling street car. drives great.
im not a know it all, this was recommended to me with my setup, so i went with it. im happy.
im not a know it all, this was recommended to me with my setup, so i went with it. im happy.
67Dart273
Well-Known Member
The standard answer which seems to work well is here
Notice that modern radials like NEGATIVE camber (wheels IN at the top) as opposed to the original bias ply specs of POSITIVE camber (wheels OUT at the top)
http://www.allpar.com/history/mopar/front-end-alignment.html
The chart:
Notice that modern radials like NEGATIVE camber (wheels IN at the top) as opposed to the original bias ply specs of POSITIVE camber (wheels OUT at the top)
http://www.allpar.com/history/mopar/front-end-alignment.html
The chart:
Mopar to ya
Well-Known Member
The best alignment is what the factory calls for. Adjustable control arms and strut rods are great and make the alignment easier, but don't change the specs. Point them the right way and save tire wear.
4 degrees positive caster. 1/2 degree negative camber. 1/8 inch toe in. thats about what my 68 cuda has in it for a performance handling street car. drives great.
im not a know it all, this was recommended to me with my setup, so i went with it. im happy.
This^^^^^ But I'll add one thing. Adjustable strut rods are NOT the correct way to get more caster. Trying to do that only puts the lower control arm bushing in a bind.
67Dart273
Well-Known Member
There has been TONS of discussion and information on this, and I don't think many will agree with you. The BIG CHANGE is due to radial tires, which "like" different setup than the old bias ply tires.
My valiant was set to 5 degrees caster -.8 camber and 1/8th" toe. It did wear the inside of the tires and took some effort to turn the wheel when stationary. The chart has good specs and mopardude318 suggestion was also good if you can get those numbers. I just hope you alignment tech knows how to change his racks settings from degrees to fractions for your front toe.
The factory specs are good if you want your front wheels to wobble like they are on a shopping cart. Factory caster on manual steering cars was negative-turns easy with no high speed stability.
The factory specs are good if you want your front wheels to wobble like they are on a shopping cart. Factory caster on manual steering cars was negative-turns easy with no high speed stability.
Mopar to ya
Well-Known Member
Well, argue if you will. Radial tires or bias tires make a difference in handling, not alignment. Alignment is geometry, nothing more. It is the angles that apply the tire to the road. I have worked in automotive service most of my life. I'm not making observations based on conjecture. Can you change the alignment to do different things? Of course you can. Will it lead to excess or uneven tire wear? Yes it will. I won't argue that you can change angles to help steering or tracking, but what you gain in one place you lose in another. My Dart is aligned to factory specs and I have no performance issues whatsoever. My tires wear smoothly and evenly. The only excess tire wear I have is in the rear wheels, and that has nothing to do with alignment and everything to do with power.
67Dart273
Well-Known Member
So I guess most of the rest of us are wrong? Amazing. My tires don't wear, either. Must be the altitude
Radial tires certainly do need different alignment specs because of their tendancy to allow the tread to contact the road over a wider spectrum of angles compared to biased ply tires. In other words, it takes MORE of a given angle to make a difference with a radial tire. Whereas biased ply tires will be in one position at say -.5* of camber, a radial tire will need more negative camber for the contact patch to be in the same position. I thought that was pretty common knowledge industry wide. Same thing that makes this true is also the same reason radial tires hold the contact patch on the road better than biased ply tires. The contact patch is allowed to "squirm", thereby actually allowing it to remain on the road through a wider arc of camber angle.
340duster
Well-Known Member
I have some experience with this both on my street A-bodies and my old circle track a-body. I have done lots of home garage alignments using my trusty snap-on bubble alingnment tool. One guy even took his car to the dealership to get it checked and it was perfect! Here's are some of the things I learned, run as much caster as you can, the wheel will return to straight ahead (after turning) much better plus the car will have more road "feel". Road feel is the wheel wanting to return to center. Put in zero caster and see what happens - you wont know when the wheels are straight or turned. You will be have difficulty getting much caster without using the offset bushing kit. For manual steering on the street I wouldn't go much past 2.5 degrees caster as it will be difficult to turn when going slow or stopped. Definetely don't use the stock specs, some of the manual steering cars actually called for slightly negative caster! (bad - the car will steer like crap). You can't go too far wrong with the typ performance street on the chart above. If they cant get the caster you need you will have to install the offset bushings.
pauly v.100
Well-Known Member
mine is set up for "spirited" cornering, not nessesarily track duty.
camber: L. -1.0 R. -.08
caster: L. 5.7 R. 5.9
toe in: L & R .05
with my current suspension and wheel/tire setup, a factory spec alignment would be undrivable.
camber: L. -1.0 R. -.08
caster: L. 5.7 R. 5.9
toe in: L & R .05
with my current suspension and wheel/tire setup, a factory spec alignment would be undrivable.
Sorry, but this is flat out wrong. The original alignment specs were for bias ply's, and that has EVERYTHING to do with how the cars were aligned. Wear patterns on bias ply's vs radials are completely different, not to mention handling characteristics.
The whole point of an alignment is to keep the car driving straight and maintain the best contact patch for your tires to improve stability. An alignment to original specs with radial tires will do you a serious disservice when it come to handling. While it may not wear tires, it absolutely decreases the handling performance of your car.
This is true even with 14 or 15" radials, although its really true if you're running 17's or larger. If you upgrade to more modern sizes and tire compounds, you may even see abnormal tire wear with the original specs. The difference in compound and side wall stiffness is HUGE, like comparing hockey pucks to silly putty.
The SKOSH chart posted above is a great recommendation for alignments with radial tires, and a good place to start. I'd say that the chart's caster recommendations are great for manual steering, and low for power steering. No reason not to run +4 degrees of caster on a power steering car, even for the "granny" setting. That's about the top end of a manual steering caster setting though, as it will make it a little too "stable", the wheels will get a little hard to turn.
With my 17" rims and tires I've run as much as -1 degree of camber without seeing any abnormal tire wear, although I drive a lot of mountain roads. Modern performance tires are DESIGNED to run negative camber, and tolerate it well. A set of BFG T/A's will not do as well, and I don't think I'd run more than -.5 degrees camber with them. Negative camber keeps the inside wheel upright during a corner. While its under cornering load the tire will increase the camber on the inside (loaded) wheel. You want your dynamic camber to be close to 0 to keep the best contact patch, starting slightly negative means that under cornering load the tire will move toward 0 and maintain more contact with the road on the most important tire. If you start out with positive camber you'll get more positive camber as you load the inside wheel during cornering, and you'll put less tire on the ground. Less traction. The ONLY reason the factory spec calls for positive camber is because the bias ply tires can not tolerate negative camber. They don't have the sidewalls to maintain it. It has nothing to do with the best geometry for the CAR, and only to do with what the tire technology at the time could deal with.
Toe in is just to "take up the slack" in your steering joints, as the slack will cause the tires to toe out during driving. You want your dynamic toe, the actually toe while you're driving down the road, to be close to zero. If you're running modern tires and new steering components, 1/16" toe in is plenty. If your steering stuff is a little more worn, up to about an 1/8" will work great.
My Challenger is currently set up with -.7* camber, +4 degrees caster, and 1/16" toe in. For a cruiser a little less camber would be good, say between -.25 and -.5 degrees.
You may have to take it somewhere other than a "chain" tire or wheel place to get that alignment though, a lot of the chains will only let the guys put in the alignment thats in the computer, which is the stock spec. No amount of arguing that those specs are for 1950's tire technology will help, the factory specs for our cars were outdated even when they came off the assembly line.
My*65*Dart
Well-Known Member
I rebuilt my front end an did my own alignment. Set mine up from the chart that was listed above (just above Granny). I have 14" radials and it handels good with no unusual tire wear. Have always heard that you DO NOT want to set them up to factory specs if runnin radial tires. If runnin bias ply it would be ok.
ok now I'm getting overwhelmed here,First it is a MANUEL box car running on the street at this time,It is going to a custom shop where they will set it at ANY spec's I give them,SO Am I to follow the chart posted above????? Did not mean to start any fight's or heated discussions just looking for suggestions from someone who has the same kind of set-up---Steve Car is a 70 Duster with factory k-frame--Thanks GUy's
69383valiant
It is what it is...
Subscribed, I was also in need of this info. Thanks guys....
pauly v.100
Well-Known Member
go with the specs in the chart and you'll be happy.
I'd use the SKOSH chart above then. The only difference with manual steering is the amount of caster. More caster = more stability, but it also makes the steering feel heavier. For a power steering car, especially our overboosted power steering mopars, thats a good thing. For manual it makes it a little tougher to steer. The SKOSH chart is right on for manual steering, I think its a little conservative on the caster recommendations for power steering.
As I mentioned, mine is set up for performance street driving, -.7* camber, +4 degrees caster (its power steering) and 1/16" toe. Works great, no abnormal wear. But I run 275/40/17's, so modern performance tires with a short sidewall. For 14's or even 15's I'd say more like -.5* camber.
buck351
Well-Known Member
I was replacing torsion bars on the 67 GTS with 1" bars, no adjustment left on driver's side on the original one. I remember seeing this post so I had them try and use these settings since I have radial tires. Well with the stock adjustments they got close on the camber and the best they could do with the caster is less than one degree positve which is better than the stock setting. Drives better than it use to now.
Sounds about right for the stock bushings. With the Moog offset UCA bushings you can get more caster.
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