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Pantera Performance center sales Wilwood. The hats are alum and they will move the rear wheels out 1/4". The fronts still stay inboard mount.
Precision proformance sales a brake set up that uses corvette brakes. The rear are outboard mount, I am not sure of the wheel additional off set. I think it is about 1/4".

The wilwoods can be either the stock thickness or 1 1/4" thick rotors. You will need to buy a new part brake with the thicker.
Precision are not as thick as the thicker wilwood and come with park brake.

Kevin
Boyd,

Sent you this via the e-mail list, but I'll post here for everyone's benefit.

I have moved front and rear rotors outboard on my '74. On the rear I used Sierra hats & Wilwood rotors, up front was Wilwood hats and Coleman rotors. Calipers are all from Sierra.

The particular rotor isn't as important as the caliper mounting brackets depending on what style/width rotors you want. At the rear I went for vented 1.25" rotors in 12.19" dia. 8x7.62" bolt pattern (Wilwood part #'s 160-2900 & 2901). You can get the same rotor in 0.81" thickness (part #'s 160-8474 & 8475) if that suits your current calipers better, but you'll still be making mounting brackets to move the calipers out as that is still a larger dia. rotor than stock.

The Sierra hats are a Larry Stock exclusive as he purchases blanks and drills them for the 4.5 x 5 bolt pattern. For the fronts I used an off the shelf Wilwood hat part # 170-0635 to move the rotors outboard.

Sierra will refer you to Larry if you enquire about their hats/calipers for a Pantera, but I found his prices not too overinflated to Sierra's direct pricing. You will likely need to change your wheel studs for ones with a slightly shorter shoulder length in the process (or chamfer the back of your wheel mounting holes) as the hats are thinner than the oem rotors.

Here's Sierra's website http://sierraracing.com/

It will push your wheels further out by the thickness of the hat, which is about 0.3".

Julian
Thanks for your reply. I am going with Brembo calipers that are from a porsche 996T ( a 911 Turbo) The calipers arearound 13.1" ( I don't have the exact #'s yet. This is a conversion put together by ken Green and includes mounting brackets custom made to the calipers and rotors he has selected. The rotors and hats are colemen. I don't have the model #'s or dimensions yet. I am supposed to be getting them this week. I will look into the info you gave me. I really appreciate it.
Thanks.

Boyd
Boyd, I mounted my brake rotors outboard of the stub axle by using Coleman billet hats. I did this conversion (with Porsche 993 Turbo brake calipers) nearly ten years ago but I'll see if I can find the specs I used. Previously, I had been using Wilwood hats, mounted in the stock location. All I did was increase the offset of the hat by the thickness of the hub and made sure the I.D. of the hat was sufficient to go over it (the hub). While I was at it, I replaced my stock wheel studs with 1/2"-20 items. Before you attempt this conversion, be aware that some Pantera stub axles have a slight taper to the wheel register that protrudes from the stub axle's hub, so if you put a 1/4" thick brake hat on the outside of the stub axle, your wheels will no longer be hubcentric. This can be dealt with in a number of ways but keeping your wheels hubcentric is very important.

Ron, please explain your comment:
quote:
I dont agree with the ease of changing a rotor and mounting on the front of the axle or splindle ... this means the wheel when bolted on determines how true the rotor will pass thru the caplier ...no good.
I don't see what the wheel has to do with the trueness of the rotor. If the face of the axle is true and the rotor is true (and hubcentric), then the wheel has nothing to do with how the rotor passes through the caliper.
Ron,
I wonder how many Pantera owners don’t use a torque wrench to tighten their lug nuts! But seriously, I have measured the run-out of my rotors with only two lug nuts holding them on (tightened by hand), and it measured ZERO. Once again, if the rotor (incl. hat) is true and the face of the stub axle is true, there’s no issue with mounting the rotors on the outside of the hub. That’s how Porsche, BMW, Mercedes, etc. mount their rotors. In fact, I believe De Tomaso mounted them like that on the ‘90’s Si models (with Brembo brakes).
Your comment “and if this was meant to be why didnt it come from the factory this way ?” surprises me considering the major changes you’re making to your braking system.
On the subject of brake hats, be aware that the Wilwood hats, that most Pantera owners use, are notoriously “un-true” when new. Every one of them should be checked for run-out prior to installation. Marino Perna (Pantera East) told me that he checks every single one he sells, before it goes out the door. He went on to say that a startling percentage of them are “out” by some degree, and need to be re-machined in order to make them perfectly true.
Ron,
First of all, I do believe most Pantera owners use a torque wrench to tighten their lug nuts. No, that doesn't mean that I think they carry one around in their trunks.

There is no technical advantage to mounting brake rotors on the inboard side of the hub. I'm not sure what De Tomaso was thinking in 1970 when they were designing the Pantera but I do know what they (and Brembo) were thinking when they designed the brakes for the 1990's version of the Pantera (the Si); with outboard mounted rotors. I guess Porsche, BMW, Mercedes, Ferrari, etc. are all thinking the same thing, or perhaps Brembo is doing their thinking for them!

Outboard mounted rotors don't move your tires closer to the fender if you purchase wheels with an appropriate offset, that takes into account the added thickness of the hat. Bearing loads are not increased for the same reason. If you don't believe me, ask Dennis Quella.

My original set of Wilwood hats were all un-true but that was about 15 years ago, so maybe they've cleaned-up their act. Furthermore, I'm not blaming Wilwood for anything. My hats were "off" so I trued them up in a metal lathe. End of story. I only mentioned this because Marino Perna told me (also 15 years ago) that he had found the same problem. The bottom line is: any brake hats should be checked for run-out BEFORE bolting rotors onto them, not just Wilwood hats.

I checked the run-out of my rotors with a dial indicator. I don't know of any other way to do it. I suppose you assumed I had the wheel mounted at the same time !!! Nope, just two lug nuts to snug the rotor to the hub.
I personaly had not given it much thought but after reading your post and thinking about it you have a valid point. Leverage is one of the miggest force muitipliers. So it makes sense that any extension of the wheel mass would be something you would want to avoid. By extending the hat to the outside you are increasing the leverage the entire wheel mass exerts on the axle and the bearings. Even at the small numbers
we are talking about (in regard to increased length of the out side mounted Hat) With the common increase in wheel diameter , weight,and tire width the amount of mass and stress on the components is already increased substantailly beyond the original design values.Increasing this mass, then increasing the leverage by extending the hat length and using aluminum instead of steel sounds like a recipe for trouble. This is all hypothetical but to me it makes sense. When you consider the ramifications of a failure ( possible loss of a wheel, damage to the other compnents including possible body damage and the risk of death if you lost a wheel at a critical moment) all seem like good reasons to make every effort to REDUCE the forces exerted on this area not increase them.
Just my opinion (all based on hypothesis )"your results and opinion my differ"

Boyd
Ron, your claim that moving your hats to an outboard position does not alter there position (ie closer to the fender) assumes that besides changing your hat you are also ordering new wheels at the same time. In my case I had already ordered and paid for my wheels. At $3500.00 I wasn't going to order new wheels to compensate in the .3" change in offset. I would agree that if you were buying new wheel , new brakes and totally reworking youur rear suspension you may be able to simply alter your offset to compensate for the difference in positin for the wheel caused by the extension of the outboard hat. There is another issue they may effect your ability to pick up the extra .3" normally gained by mounting an out board hat, and that is caliper size. While I was exploring reworking my rear suspension the whole process was actually initiated by my desire to install new brakes to go with my new wheels. While creating my brake template for the wheel manufacturer I realized that the caliper rotor assemblies over all diameter was not the only size increase I had to worry about. I had not even occured to me that that the brembo mono bloc calipers where thicker and
they would have prevented me from changing my offset to move the wheel in the additional .3"
needed to compensate for the change in the wheel position caused by the outboard hats.
So there are apparently no absolute truths in either position. You may be able to compensate for the increase in out board wheel position caused by using the outboard hats ( and have no change in the position or forces) But that can be a very big if ( like having to buy new wheels and revise your brake choice) and on the same token changing to outboard rotors may in fact change the wheels position to one closer to the outside fender and subsequently increase the forces exerted on the suspension components.
So in a perfect world where you totaly revise several major components of your rear wheel/ suspension assembly you may not generate any additional forces, but in the real world where modifications are made when some other incident effects your decision to make a modification Like repair a worn rear rotor and once they realize what a pain in the butt it is to change the rotors and someone tells them they can simplify the process in the future by installing out board hats the the facts are that there will be an increase in the forces exerted which is a contradiction of your statement that there will be no increase in the forces exerted.

Boyd
I think you guys are arguing semantics here, 0.3" is nothing on a car where tolerances are generally measured in weeks Big Grin. Most play is usually in the axles themselves and did you all add new a-arms with heim joints not rubber or poly bushings etc. Don't most have aluminum wheels to go with those Al hats, but wheels don't suffer heat expansion?

Hey, you can always go the Corvette style route with inboard brakes on the transaxle side and remove the unsprung weight altogether, Ted Mitchell sells a system.

Yes it's imprtant to make sure any new brake system is compatible with the wheels you are using and caliper to wheel clearance can easily be overlooked.

Agreed that the vendors Al caliper brackets are one up from useless.

Julian
Last edited by joules
Inboard brakes are not widely used because if you break any part of a half-shaft, you have no braking ability on that corner of the car. Otherwise, the advantage in the reduction of unsprung weight would override any maintenence issues.

I had my brake adapters machined from steel; however, and in the defence of our Vendors, I don't believe there's ever been a case of an aluminum caliper adapter breaking.

I'd also argue that Coleman's brake hats, which are machined from forged billets of 7075 aluminum, are significantly stronger than Wilwood's generic, non-forged hats, albeit four times the price. They can make them for conventional mounting but because they're thicker, no shims are required between the base of the wheel studs and the hats. That being said, the Wilwood hats are certainly adequate. I just got carried away . . . again !
Last edited by davidnunn
TO AC Cobra,
I did not mis quote you, in fact I was defending your position. It Was the other guy who said (and this is not an exact quote) installing out board hats does not chnge the position of the wheel (if you compensate for the change in position by altering the wheels offset)
I said most people were noy going to buy another set of new wheels, I just spent $3500 and I wasn't going to do it again to make up for the .3" I would gain in length if I went with out board hats. ( that was defending your position that the out board hats move the wheels closer to the fender) I also said that adding legth to the wheel mass (and doing it with aluminum instead of steel) was a double whammy because more length = more leverage =more stress. So next time try to realize who is basicaly agreeing with your position and don't assume they are quoting you.You are so wound up in defending your position you don't realize when someone is agreeing with you.
Boyd
Just for kicks and to satisfy my curiosity I asked the Wilwood Tech guys what their thoughts were on rotor mounting. They said they have no experince of mounting hats behind the axle flange and would always recommend the hat on the outside so the wheel tightens against the hat.

Julian
quote:
They said they have no experience

So who are we to follow??

Some telephone tech guy who probably has never even ridden in a mid-engined car with exotic pedigree, or our illustrious benefactor, the late great Alejandro and his skilled team of designers, engineers and craftsmen?

Let's ask Tom about this in Monterey. THAT should be good for some friendly banter.

Big Grin

Larry
Talk about not getting personal! What is your malfunction. I defended your position . I agreed that using outboard hats would alter the position of the wheel by brining it closer to the outside (the fender) I also agreed that using aluminum for a part that was going to be subjected to more stress and using a weaker material for the part was a bad idea. I also pointed out that the oyher posters stattement that the use of outboard hats would not alter the position of the wheels was not really accurate because most people wouldn't be willing to order new wheels with altered offsets which would be neccesary to make his statement ( about the wheel position not changing untrue). Sure he could get the wheels and dimensions to wind up just about anywhere he wanted to if he is willing to spend a ridiculous amount of money. Before I would spend another $ to make new wheels with adjusted offsets to compensate fot the repositionng of the wheels furthur out and closer to the fenders I would spend the money on CV joints and custom rear suspension that would improve the accesability of the rear rotors and improve the transfer of power to the rear wheels, and improve on the antiquated ball bearings. You still didn't pick up on the fact that I was supporting your basic position that any convinience you might pick up using aluminum hats to install outboard hats was out weighed by the additional problems that such a modification might cause. Aparently you don't like people agreeing with you anymoore then you like people disagreeing with you. Why do you bother gettinng involved in a diaoluge. Just send your self an e-mail and then you probably won't get into a disagreement. But if this last exchange is any example you will probably still argue even though you are the only one participating. You have no idea how I use my car, how it is equipped and how I drive it. So before you tell me to just paint my calipers take a look in the mirror. I'm not convinced you even know what that guy is doing with his car let alone what I am doing with mine. I have had several sports cars over the years that ranged from stock to race equipped and not street legal. I have also had an offshore race boat, a worked 750CC Kawasaki race jet ski and a variety of motorcycles. I crashed my NSX at over 150MPH. So don't assume to tell me what to do with My Pantera. I don't talk about my other go fast stuff because this is a pantera forum. What happened ? Did they throw you off the Cobra forum or did you stop participating because you already knew everything?
Boyd
quote:
antiquated ball bearings

If they are old, they are antique. But if it is just the design that is old, they are time tested. Ball bearings are used in current top-of-the-sport racing. They are far from inherently bad or inferior to tapered bearings
quote:
I crashed my NSX at over 150MPH

I crashed my Pantera at about 65MPH. Driver error. I could easily crash an NSX at 150MPH using the same technique. Big Grin

I don't think you gave yourself any credence with THAT admission. Wink

Larry

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Boyd,

I'm sorry to hear about your accident. Not many people survive 150 mph crashes. I bet I know what happened ... those bastards at Wilwood convinced Acura's engineers to design the NSX's brakes with the rotors on the outside of the hubs. When you drove it that fast the additional width of the rotor created stresses and metal expansion from heat and O.M.G... total catastrophic failure of the brakes and suspension! It's all Wilwood's fault! roll on floor

Boyd, I'm not making fun of your accident; just trying to lighten things up. It's a good thing I didn't tell your friend Ron that he should be using floating rotors on a car that's used regularily on a race track!!! (oh, that would sure "open a can of worms").

David
Last edited by davidnunn
Boyd,
For the sake of the participants in this forum, please don't respond to accobra. His postings are just too painful to read.

Also, when I was looking to upgrade my brakes, I asked Gary Hall which kit was best. His answer was the Brembo kit, which moves all 4 rotors outboard, to between the hub and the wheel. Obviously, Brembo knows what they're doing but I just couldn't swallow the price ($8,000).
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First of all Pantera 4134 : I believe if you check your facts you will see that you are incorrect. I have only criticized someone on the list because of their opinion once, and that was because that person was ranting on about how they had blown the doors off of a number of what I considered to be quality sports cars with his Mitsubishi 3000 GT. He also said that an NSX was a piece of shit. I took exception to his opinion but I didn’t get personal until he did, and my problem wasn't with his opinion it was with him and his personal attacks.( If you care to attempt to support your claim that “From following your posts on the “Mailing List” you seem to have problems with differing opinions.” I would like you to show me an example of a case where I criticized someone for their opinion. (other then the 3000 GT guy which was over a year ago) I don't criticize people for their opinions. I may question someone’s opinion (that’s what a meaningful dialogue is all about) If a person has an opinion they should say it's their opinion . There is a difference between an opinion and a fact. If someone makes a statement and claims it is a fact they should be able to and prepared to provide proof. That's the basis of the scientific process and the legal and educational system. If you make a claim be prepared to back it up with facts and provide the source of your "statement of fact". I may strongly disagree with an opinion, and I may be less diplomatic if someone confuses their opinion with factual information , but I do not and I did not criticize the person just the opinion .If you take the time to read all of this post you will see that it was ACCOBRA who got personal and nasty. He and I believe it was Julian were having a difference of opinion about the merits of outboard hats. I made statements that basically defended ACCOBRA'S position but I also said that there was some truth to both of their positions. He ( who apparently has some trouble reading and keeping the facts straight) said that I misquoted him when in fact I was repeating Julians position not ACCOBRA's. When I pointed out this error to him and the fact that I had been supporting HIS POSITION he said (This is an exact quote )"Basically who cares unless your pounding on the car like I do with my B2, AC or 9138 on a track ... otherwise street driving .. paint your rotors and calipers red like the tuners so you can see them through the wheels ...because you most probably will not see the benefit of an upgraded braking system ... so save your money." Implying that I don't drive my car hard enough(like he does) to need upgraded brakes That's why I mentioned crashing my NSX at 150 MPH to point out that he has no idea how I use or drive my cars and telling me to "just paint my calipers red...and save my money" was a personal insult. So it appears it is he who has a problem with people who don't share his opinion's (or he is just paranoid) because I was supporting his position NOT disagreeing with him and he couldn't tell the difference! So I will ask you to Support YOUR OPINION about me having a problem with other peoples opinions with some form of FACTUAL PROOF or retract it. I don't recall you telling ACCOBRA to "Chill Out". Larry I qualified my position early on by saying that I was not an engineer but I based my opinions on my own understanding of physics. My mention of crashing my NSX at 150 mph was not meant to lend veracity to my qualifications as a mechanical or brake expert but instead to show that I did in fact drive my cars at a level that would or could benefit from improved brakes (or at least improved beyond 1973 technology). I don’t quite grasp how your disclosure about crashing your NSX at 65 mph has any relevance to my credibility or to the topic of the post, if you were trying to establish something about your driving skills you succeeded. Finally as far as the question of whether ball bearings on the rear wheels of the Pantera are antiquated or not I should have defined my position more clearly. I know roller bearings are used on most high performance cars including race cars. When I said "antiquated bearings" I was refering to the roller bearings on the Pantera. They are inadequate to support the added stress caused by the larger wheels and tires that are more common on Panteras today then the 205/50/15's that were on my 1973 L. If you read the July Pantera Club of Northern California newsletter there is an excellent article by Mike Drew about an updated roller bearing replacement that is double the width of the stock ball bearing. Mike’s article also points out the numerous deficiencies in the stock roller bearing assembly used in the Pantera. This is what I was referring to when I said “The antiquated roller bearings in the Pantera” Here is the link to that article if anyone cares to read it. The improved roller bearing only costs around $12.00 more then the stock bearing and Wilkinson Pantera sells the bearing and the narrowed spacer you will need if you replace the original with the wider bearing.
http://www.panteraclubnorcal.c...rticles/News0907.pdf

I am also attaching a picture of my NSX . This is to show you the difference between a 65 mph crash and a 150 mph crash (in an NSX ),most other cars would have suffered much more damage and left me dead) and to show that when I say something I can back it up with proof, I have also included me on my jet ski I mentioned and my offshore speed boat.

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To: Pantera_74_GTS,
I am in the process of doing an ugrade put together by Ken green. He uses Brembo calipers from a 996T (which is a 911 Turbo). He doesnot provide the rotors or hats , just the calipers and the mounts. He tells you what size rotors and hats
( he recomends colemen as the source for the rotors and wilwood for the hats.
He is also almost finished with a Billet carrier that includes CV joints and makes the rotor installation or switch much simpler. It does away with the mongo axle nut and uses a heavy duty bearing . I have attached a picture of the carrier with a view from the back.
Boyd

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Your reply is exactly what I expected. You jump into a post that was a serious effort to ascertain information about improving the brakes of the Pantera. I am in the midst of upgrading my brakes and I want to take advantage of the expierience and opinions of other Pantera owners that have done this before me. I am the person that started the post. You jump in not knowing shit. You have nothing to contribute to the topic. You make an acusation to me about not being tolerant about other peoples opinions and then when your called on your baseless acusations you have nothing to say to support your accusation of me. Then you come back with a personal attack. What a hypocrit! The only reason I posted the pictures is because apparently there are other people besides you that are also full of shit so I put up pictures to prove what I said was true. After the sarcastic remarks about my crashing my NSX and not needing to speend the money on brakes since I "don't drive hard" I thought I would follow the old adage of "Put up or shut up" Why don't you do the same?
Boyd
Hugh Boyd Casey _ I don't have to hide behind some alias.
Okay, back on subject....

I'd like to uderstand more on Ken's brake upgrade and billet upright. I understood Hall did billet uprights some years ago and they suffered from problems. What engineering has gone into Ken's product?

Where is Ken's upright/axle system designed to have the hat sit or is that a personal choice?

The caliper mounts are specific to a rotor size and hat offset so it would make sense to supply it as a complete kit in my mind.

The additional width from having the hat outside is nominal and no more than the variation in width between tire manufacturers, so I don't think new wheels comes into the equation.

Respectfully,
Julian
Ken is really the person to answer your questions but I tell you what I know so far.
The rotor and hat sizes are determined by which Brembo caliper you use. He does tell you exactly what size and model rootor and hat to get but since the rotors are made to your specefic specs (like vented, cross drilled etc.)
He suggests you order them yourself (and save some money The axle nut and the hub and bearing are a complete different setup then stock, so there is no more monster axle nut with 300 lbs of torque to remove the rotor. The axle does not need a press to be installed . So in essence it is an out board hat but not the same as an out board hat on a stock set up.
These are the questions I asked him along with his answers. I have several pictures of the carrier and the Hub but I don't know how to post more then one picture so if you send me an email addrees to boyd411@gmail.com I will send you the pictures I have. Here are the questions an answers:
1. So with this design you no longer have the Monster axle nut that takes the 300 lb torque to remove the axle / rotor ?

No mondo nut

(so future access to the rotors for removing or replacing is vastly simplified .) You just remove the wheel and the new small axle nut?

I don't want to over simplify it, but you remove the wheel, hat & rotor, one large (not 300 ft-lb) axle nut, and three bolts holding the hub an bearing assembly.

2. What kind of bearing is used inside the carrier?

I'd have to ask Ed. He uses these in off road race vehicles, I'd guess they are a lot harder on bearings.


3. With this design is it still necessary to use a press to push the axle through the carrier, or does everything just bolt together?

The axle and hub have spline that engage. I guess things can always get stuck, but this design does not have a press fit bearing like the original.

4. Are the CV joints included with the carrier?

the CV half shafts are part of the kit and each includes 2 CV joints and bolt to the rear of the stub axles.

5. How does the top a arm attach to the top of the carrier?

Same ball joint taper fit as stock carrier

6. What old parts from the original carrier( like the axle ) are used in the new assembly ?

None

7. Are there any other parts (besides the caliper,rotor, and hat would I need to purchase in addition to the things included with the new carrier assembly to complete the conversion or is everything needed included?

Maybe brake lines, I need to talk to Chris about what he is using, and Master Cylinders

8. When do you anticipate the completed package to be completed and ready for delivery?

We are hoping to have something to put on Perry's car in about a month. The kit with the little brakes has been on a car for a few months, and was driven to Reno, so most of the kit has been tested. But we want to find any installation issues before parts are shipped. The kits will be sold by Ed, not us. We are just helping get the design finalized.

So if you want more info you should speak to Ken
He is offering a wholesale deal for the first ten upgrades. If you compare the price to doing the same thing through the vendors you will see it is a good deal ( my opinion) I am giving it serious consideration even though I don't need new axles or half shafts or bearings. But since I am changing my rotors I thought it might be a good time to upgrade the rest.
Boyd
I am not the person to ask about the details ,but I will be happy to share what information I have with you. This is a project that Ken Green (and some others ) have been working on for some time. It is in the final stages and they say it will be ready for sale in the next month or so. They have been making some modifications to the design tweaking it before they release it to the public.
In answer to your question this is how Ken described it to me. (I am attaching a photo ot the hub /bearing assembly)
"
The hub and bearing assembly is shown with and without the stub axle attached. The These parts sandwich the carrier, and tended to dictate the carrier design. You simple bolt a flange on the hub and bearing assembly to the face of the carrier, and insert the stub axle from the back, and tighten the one large nut (not anything like tightening the nut on the stock carrier) to attached the axle."

If you are interested you should contact ken green. He is on the "big list"

Boyd
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