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This has been a great forum discussion and given me allot more insight into the entire issue of alignment than I had.

6997 has yet to get to an alignment shop after the suspension rebuild, but following this discussion I have spent the day relooking at caster, camber and toe in settings.

I really tried to get the suggested settings using a simple two sting parallel line set up and an accurate 1m long level and lots and lots of measuring .

On one side I ran out of front caster adjustment, on the other side camber, so had to settle for the maximum possible in each instance and set the other side to match the measurement. I then set the toe in alignment using the two external sting lines.

It is surprising - I do think you can get the settings close on the garage floor with enough care.

I will have this car into a professional alignment shop shortly and will admit to the forum how far it was out when they put it on the computer!

Thanks again for all the knowledge poured out into this discussion.

For the adjustment of the parallelism, I have this tool:

https://www.ebay.com/itm/30081...3:g:NAwAAOSwC3Zdlzpa

which is simple but precise, the reproducibility of the measurements is very good. Obviously it does not take into account the veiling of the rims but by taking 4 measurements at 90 ° and by taking the average we can compensate.
In addition, we must not forget that ultra-precise measurements are useless on a street car whose suspensions are mounted on silentblocs. It is different with racing cars completely mounted on ball joints.

Thanks Rene .

I looked at the Utube user guide on the Trackace Laser Wheel Alignment System and it looks very accurate . It is something I may well buy - it is brilliantly simple and is affordable. Thanks for sharing this .

What do you use for caster and camber checks - any other pearls ?

Plainly my existing  tool is not so flash.....!!!

But it is multipurpose.

You can always use it to hang up stings of garlic or onions if it goes out of calibration !



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  • mceclip0: String theory
@bosswrench posted:

*- Agree. My #4366 did not have them either but I've heard of a few '72-1/2 L's having them as well as most '73-up cars. Simple flat 8mm/5/16" thick bump-steer spacers have a part number listed in later Illustrated Parts Lists and in the European GTS/Gr-3 Supplemental Parts Lists, but like most Pantera upgrades, there is no hard date for their introduction. I call it an  'L Model Thing' that carried over to '80s wide body cars at least thru the '87 GT5-s cars.

I had purchased my offset poly bushings from Hall as a kit over 20 years ago and can't find any on line listings for them now to help others with this situation.

Can anyone here point to current vendors who offer them?



Quote: "It is surprising - I do think you can get the settings close on the garage floor with enough care."

Who love's ya' Babe!



Camber and toe in are EASY. Toe change is more work but doable. Compare on the ground to hanging and see if there is a difference.

Castor is difficult to do accurately without an accurate machine. You can only estimate it without it.

Last edited by panteradoug

Thanks Doug.

I admit to cheating on the Castor - I assumed the original set up had some science behind it and reassembled with exactly the same shim groupings and positions on the upper a arms before the suspension rebuild.

This was all in on one side but split shimming on the other. Interestingly the tie rod thread offsets turned out exactly equal on both sides of the car when the rest of the alignment was done blind, so I don't think it is too wrong.

I will soon know! 

Thought Bosswrench's comments were very informative, especially on front end "tire scrub".  My "74 Pantera is #6834, which I bought "brand new"., I  remember bringing  the car in for a front end alignment  and the tech spent over 2 hours on it trying to get over 0 degrees positive on the front left side, with all the shims on the front side.  I wasn't that knowledgable on Pantera front suspension quirks way back then,  but figured something wasn't quite right.

About  9 years ago, I had a spare left and right pair of upper "A" arms sent out to  and modified by Pat Michal for additional upper ball joint "back and forth" travel for additional caster adjustment and "in and out"  travel stops for camber adjustment.  That cost was about $900 with new bushings.  My car is a 1974 #6834, yellow in color,  I bought new from Fore River Motors in Quincy, Mass in March of 1975.   It still wears its original paint that looks great.  Sent the car to the alignment shop with new Coddington Campo aluminium epros by (Mario Perna in Florida)  front rims 10" x 17" with 245/40x17" front tires and 13" x 18" rear rims with 335/30-18" .  I forgot the exact rim offsets, but they were perfect with little room to spare for fender clearance on a stock bodied Pantera, but they fit like a glove.  Mario Perna did do his "homework" on this fitment.  The rear 18" rims were great as the allowed more offset by tucking the lower upright bottom inside the rim ID.  I don't know what the front tire "scrub" was , if any.  We ended up setting the front end caster to 4-1/2 degrees positive on both sides with camber and toe-in to factory settings.  Rear toe-in was correct factory setting after juggling shims for toe-in and camber.  Not sure if you still get these size and offset Campo repro aluminium  rims anymore.  Tightest clearance was tire wall to late 70's Mind Train exhaust mufflers with 2-1/2 system with headers.  Got pretty "busy" with all the rear end and exhaust modifications, but it works.  The car now drives great with great high speed (120 MPH plus) stability.  Steering is high on parking, but tolerable.  Once your moving its fine, and you do not need power steering.

Peter, tire scrub is simply the offset between the pivot center of the front upright and the center of the  tire tread. The offset can be positive or negative. Experts say that some  (undefined) scrub-radius is necessary to prevent a very nervous handling car due to tire kick-back and to use desirable self-aligning torque of the front tires in turns. Conversely, minimum scrub is reportedly vital in front wheel drive cars to prevent torque steer. Gianpaulo Dallara- who designed the Pantera chassis- is a very talented racing engineer, so I'm sure he did his best. But probably due to geometry quirks unknown to non-automotive engineers, 'some' tire scrub is common or unavoidable on most cars.

Ackermann toe-change is another such thing not well known. I checked our Pantera for Achermann many years ago, and yes- we have some.

@Percy posted:

Thanks Rene .

I looked at the Utube user guide on the Trackace Laser Wheel Alignment System and it looks very accurate . It is something I may well buy - it is brilliantly simple and is affordable. Thanks for sharing this .

What do you use for caster and camber checks - any other pearls ?

Plainly my existing  tool is not so flash.....!!!

But it is multipurpose.

You can always use it to hang up stings of garlic or onions if it goes out of calibration !



Use "Mason line".

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