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I did a search on uprights and found one mention of replacement, and it is a very nice steel weldment.
I am surprised the weight of the cast iron upright isn't common a topic here. I thought the upright and disk assembly was heavy for un-sprung weight. I didn't actually weight the assembly after removing but it felt heavy getting it to the bench. I searched the common venders but didn't see any aluminum versions, but I did find this: http://www.epantera.com/suspension.htm

Is the weight of the upright a reasonable concern?
If I fabricated an aluminum weldment would that be overkill?
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Unsprung weight IS important. Steel BOX-construction would be great. Of course, aluminium is possible but I doubt there will be any benefit. The E (flexing) module is proportional to weight, so there is a greater selection of material in steel.
Billet upright will allways be heavier as one side must remain OPEN. And to recover torsional strength, material thickness must be added.
I made a BOX casting, but this involves sky-high tool fabrication and will not justify fabrication. However, my uprights weight 8,8 pounds and standard iron 13,75 pounds.
You may have a look at my site http://hem.passagen.se/hemipanter/
A bit down the side of the site.
An A-arm may justify an "open" billet profile since there will be mostly straight loads. But an upright is exposed to a number of load directions. And serious racing uprights are allways of the box type.

Goran Malmberg
I am installing a billet suspension from JHP Motorsports. At this point, we have the a arms on the car and the uprights are getting cut on the CNC in the coming weeks.

I see that you are using the DeTomaso specific ball joints with your setup. One of the cool perks of using the JHP kit is you get new modern ball joints and new hardware for the mounting points.

I have some pics up on my website. The information was slapped together in about 10 minutes and needs to be cleaned up mucho so don't pick on me for the lack of pretty formatting and text...


www.jacobsracing.com/susp.html

Greg

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Crash Test Dumba$$
#3988
Halls rear uprights are (or were at one time) made of 7075 aluminum, but no mention is made by anyone making alloy suspension parts of heat treating after machining. Cutting, sawing etc heats and changes billet aluminium, and in the Aeerospace game, we assumed that ALL machined parts both steel and aluminum reverted to T-zero strength (that is, fully annealed) regardless of what heat treat level you started with. Proper heat treating of aluminum parts can easily double the costs of machining them. 7075 t-6 would be an excellent material to use as its about the same tensile etc as mild steel, but t-zero is weaker. 7075 is also unweldable so a mistake in machining is not repairable.Some hobbyists like me have machining capabilities, but proper heat treating (and testing to verify your results) of aftermarket parts is very rare. I know of one owner that adapted Halibrand cast aluminum racing uprights, but that adaption was a chore since the rear upright was intended to be used with a Corvette type suspension (no upper ball joint). I also remember seeing one racer at a 'Vegas open track on the trailer early. The lightweight a-arms the owner built, bent during an off-track excursion. Not a crash, just ran off the track into the dirt, and that was enough to overstress the front suspension. Testing is important, too....
If your looking for ball joints please drop me an email. Charles.buthala@trw.com We make all sorts of ball joint designs with different configurations. I have used some of the cross axis, Heim joints with seals, on my shocks. Seals from anouther on the front upper and lower stock BJ's, and am working on sta. bar links with ball joint ends. If you would like some of the ball joint theory I would be happy to help. This is not intended as a solicitation but a sharring of info.
Yes Scott,
You are quite right,the Hall uprights (billet) ARE lighter. Hall says in his catologue that they are 17 lbs.lighter each side. Sounds like alot, but looking at the orginal pieces i believe it.
Boy, thats one aerea where the orginal stuff needs replacing big-time,with new generation,higher-tech.bits.I have for many years (bought my first De Tomaso in 1969) been battling to get my Pantera to handle decently on track day. and then when you got it working reasionably well,the settings 'vanish' into thin air as the geometery changes over time & numeropus bups etc. Notlong time either, espescially when u put some biggish power thru the gumballs and 4.22 C /W & pinion. Body & windscreen starts cracking,(mine has.) suspension goes out of wack etc. This all requiring massive strut bars/strenghting bits (Hall)to be bolted to the body; upper,lower in frt. and rear. More weight etc. I ve even tried the route of bolting the other Hall Kit: heavy bits of metal to the frt. A- arms to try and keep them inline so to speak. More weight where you dont want it. Not good.
My final desision taken awhile ago was to start on a clean page and design the thing from the ground up, so to speak,re.the chassis etc. i went to the best GT40 chassis builder here in Joburg (has built and sold 34 of these and countless other Cobra's) that, by the way, ran rings around everything they have gone up against. Everything first done on computor, then a working, wooden, scale model of the rolling chassis was made and tested before commiting to the first prototype. This was then built and tested with some changes made before imputing everything to PC. Everything is CNC cut & naturally fully jig-welded. I now have a space-framed,fully adjustable,in all directions,- with one Allen Key via the Rose-jointed setup. This set up exhibts NO 'scrub-in' or 'bump-steer' characteristics whatsoever and maintains the entegrity of its geometery as one would hope. This rolling-chassis with wheels & tyres weighs 180 kgs. Really. Built for the road,( for the track the tube walls are thinner for lighter weight.)-not just track Day.
Try this on your Pantera. Slip your jack in at the back and slowly jack the car up and watch as the two wheels/tyres 'tuck-in'as the car rises.. And boy do they tuck in. Just like a frigging swing-arm Beetle. -no not that bad.There is no 'Bump-Steer' to speak of. The prototype blew its motor due to the G-force developed thru the turns causing a oil-surge problem, but not before we blew everything into the weeds.Will go dry sump or at least 10 quart sump & baffles. (Hall) So now we have a excellent handling, accurate looking Pantera with all the latest, hi-tech possibilities along with obviouss advantage of being able to accomodate tall, light-weight wheels and new tyre technonology. Awesome. Prototype weighed 950klgs. on the weigh-bridge at Zwartkops Race track. So, yes, -the lighter weight up-rights are the way to go to. Let us know how u went and what u think. CHEERS, tai.
Tai Krige says�
Yes Scott,
You are quite right,the Hall uprights (billet) ARE lighter. Hall says in his catologue that they are 17 lbs.lighter each side.
G
If the stock uprights are 17,75 pound each, how come the Hall upright could be 17 pounds lighter???

T
Sounds like alot, but looking at the orginal pieces i believe it.
G
Even if you looked at it, Hall should use a scale before making statements.

Goran Malmberg
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