Skip to main content

Does anyone have any suggestions for an inexpensive and effective upgrade for brakes. My car does not have a proportioning valve, has stock size front vented and rear solid rotors and a Corvette master cylinder. The calipers look like stock ones. I have a wide body GP4 with 285/40 15s in front and 345/35 15 in rear. Braking is not very effective. Since most of the braking is in front, would installing larger calipers in rear make any difference or should I just install better pads front & rear and keep the stock rear small calipers? Any advice is highly appreciated. Thanks
Shah
Original Post

Replies sorted oldest to newest

Take a moment and visit Goran Malmbergs "Hemipanter" site and grab a copy of the latest Hot Rod magazine.

According to the HR article, his lightened Hemi powered Pantera will do 60 to 0 in 98 feet. The accompanying photos clearly show stock Pantera rear calipers. Go to his website and you'll see that while he does use massive four piston calipers in the front of the Hemipanter, he says "The right pads makes the original Pantera Girling calipers more than enough for any street Pantera. The only problem is that they are heavy. Two important brake factors is, ALLWAYS a yearly change of brake fluid and the right pads". He further comments on front-rear balance, tires and more.

So the trick to stopping quick is evidently the pads and the balance. Massive racing brakes allow repeated heavy use before they get too hot and fade, stock discs just get there faster. In fact, he says the stock solid discs will offer the shortest stopping distances, because they can be clamped the hardest. How do you use your car?

The general consensus among most folks running stock brakes is the stock replacement Porterfield R4S pads answer the pad issue, which leaves the front rear balance thing. A popular idea is to delete the stock proportioning valve and very often, install a non-stock dual reservoir master. GM versions are popular, my car came to me with one. I'm not so sure that's the optimal arrangement. Goran uses side by side masters and a balance bar. That makes sense to me, no loss of pedal effort through a proportioning valve designed to limit pressure.

I have the GM master, stock calipers with R4S's and have so far resisted removing my proportioning valve, but I know that the quantity of brake dust that piles up on my rear wheels vs that on the fronts is telling me something.

I wonder just how much pedal effort there is with a balance bar set up and no booster. Has anyone been there? Is it bearable on the street and maybe some light track use (20 minute sessions) with a car 1000 lbs heavier than the Hemipanter?
Shah,

I just installed Scott's rear brake upgrade kit (SACC Restorations). I have 100 miles on it, and it made a big difference. The car stops quicker and there is significantly less nose-dive. For the last couple of years (11K miles), I had been driving with stock calipers, stock rotors, stock pads, and no proportioning valve. Scott's rear brake kit is inexpensive and easy to install. I highly recommend this upgrade.

John
Thanks everyone for your valuable advice. I've heard only good things about Porterfield pads so, I plan on doing the following:
1. Replace pads.
2. Change brake fluid.
3. Look for a GM / aftermarket master cylinder
4. Rebuilt front calipers to make sure they are functioning properly.
5. Install Wilwood rear calipers on stock solid rotors.

If after doing all of the above the car does not stop in a very short distance on street ( I don't track the car ) then, I will accept the fact that a 40 year old car is never going to brake like a modern exotic!

Larry, is there a specific GM master cylinder I should look for?
John, you mentioned having good experience with Wilwood calipers. Are there any Porterfield pads available for these calipers or the ones from Wilwood is the only choice?
Shah
Shah, I agree with (and have done much of) the above, but one other item will make a huge difference is if your car has original flex lines running to the calipers. Change them for a set of the braided stainless ones (all vendors sell them in a set) which will not expand under hard braking. I found that this and the R4S pads made a huge difference with my stock Girling system.

Mark
Hi Shah,

Here is a link to information on the rear upgrade kit which is on sale right now: http://pantera.saccrestorations.net/sak41172.html

quote:
Originally posted by PANTERASHAH:
is there a specific GM master cylinder I should look for?


With our rear upgrade kit, you do not need to change the master cylinder. If your master cylinder is in good condition, it will work great. The rear calipers were sized to work with the stock master cylinder.

quote:
Are there any Porterfield pads available for these calipers or the ones from Wilwood is the only choice?


Wilwood makes 8 different compounds for brake pads ranging from inexpensive street pads to complete racing pads. The pads that come with our kit have a very nice compound that is easy on the rotor and great on performance. If you want more aggressive pads, they are available.

If you have any questions don't hesitate to contact us.

Chris
quote:
If you happen to change your mind and go install the Wilwood calipers, you will not have the parking break unless you use the old calipers or do something else.


Mark is correct. The Wilwoods do not have a parking brake built into them like the stock rotors do. For those on a budget, you can re-use the stock rear caliper for the parking brake. If you are not on a budget there are some very nice parking brake calipers available for IPSCO for around $500.00.

Our rear brake upgrade kit is a super value at only $495.00 and the performance gain will amaze you!!!
quote:
If you happen to change your mind and go install the Wilwood calipers, you will not have the parking break unless you use the old calipers or do something else.


Scott's rear brake conversion (using Wilwood calipers) positions the calipers forward of the axle. The supplied mounting bracket attaches to the extra set of mounting tabs on the upright that are forward of the axle. This leaves the stock caliper in the stock position, which retains the parking brake.

John
As long as you're satisfied with stock width rotors, Wilwood also makes a mechanical caliper (for go-karts) that can be adapted to a Pantera as a legal parking brake. The sliding Wilwood caliper is not expensive but there are two drawbacks: first, no one (except Pantera East who may have discontinued the item) makes mounting brackets, so you'll probably have to do your own. And the assembly is a racing caliper so the pads & backing are loose in the caliper, which rattles. If that bothers you, it may take more engineering to stop the little jingles from back there.
I adapted a pair of the Wilwood mechanicals to our Pantera in '97-98 when I did a wholesale brake upgrade (front & rear calipers, 4 vented rotors, aeroquip lines & a GM power booster/master cylinder) that replaced the stock rear calipers & e-brakes, and they still work well on their original pads. They use stock Pantera e-brake cables and another little pair of home-made brackets to anchor the cable ends.
quote:
Originally posted by Bosswrench:......Wilwood also makes a mechanical caliper (for go-karts) that can be adapted to a Pantera as a legal parking brake.


Jack, did you do anything different with the standard Pantera parking brake linkage to gain more mechanical advantage? Those Wilwood cart brakes have a poor reputation for holding power.

Best,
K
Agree with Kelly here and "Legal" is a very loose term in an International forum. They certainly would not be legal in many countries that require a functioning emergency brake and would not be sufficient to pass a UK MOT test where that e-brake needs to hold against a rolling road. Depending on your rotor thickness they may need modification to widen to fit as well.

Hispec make a great spot mechanical brake which will do all the above and is designed to meet UK SVA/MOT requirements and not that much more expensive than the Wilwood Kart spots.

Go to http://www.hispecbrake.co.uk/ and the "Rear SVA Caliper Range" tab for their options which also includes combined hydraulic/mechanical calipers (Separate handbrake pads) if you want the integrated approach.

Julian
I used the Wilwood Kart brakes when I upgraded my brakes to Wilwood units as I wanted to keep the outboard weight down. I had to fab a mounting bracket and add spacers and longer bolts (available from Wilwood) to the kart brake to accommodate the wider, vented, 1 ¼ inch Wilwood rotor. So far they work great and I live in the hills so I use them frequently. You could get more mechanical advantage if you needed it by fabricating a simple lever arm under the car. I had to do that on my Cobra kit car.
quote:
Originally posted by Garvino: I have bought some parts in the past from Mark at IPSCO and remembered that they sold a parking brake kit for the Pantera. The kit comes with two Calipers, Pads, Mounting Brackets, and Hardware but does require a new parking brake cable. Has anyone tried this or had a chance to see it in person? Thanks, Devin


Yes, I have the IPSCO made units on my car. They work great. They do cost more than the Wilwood spot calipers but you get what you pay for. It is why I took interest in Jack’s post. I think he is the first I’ve ever heard express any degree of satisfaction with them. Folks on the GT40 forum have nothing good to say about them either and I can see why. Besides the fact they didn’t work, I felt the quality was poor. I literally through the ones I had away and felt they were virtually useless mass with the inability to hold my car on any significant incline. Although my opinion of Wilwood products is generally high (I have their calipers, rotors, master cylinders, etc), I think this is a matter of intended use. They subject calipers don’t belong on cars.

I suppose it depends upon you’re expectation for them. If you want something to prevent rolling on relatively flat grades, they may be OK. They are in no way an “emergency” brake and don’t even qualify as a parking brake IMO.

Best,
K
quote:
Yes, I have the IPSCO made units on my car. They work great. They do cost more than the Wilwood spot calipers but you get what you pay for. It is why I took interest in Jack’s post. I think he is the first I’ve ever heard express any degree of satisfaction with them. Folks on the GT40 forum have nothing good to say about them either and I can see why. Besides the fact they didn’t work, I felt the quality was poor. I literally through the ones I had away and felt they were virtually useless mass with the inability to hold my car on any significant incline. Although my opinion of Wilwood products is generally high (I have their calipers, rotors, master cylinders, etc), I think this is a matter of intended use. They subject calipers don’t belong on cars.

I suppose it depends upon you’re expectation for them. If you want something to prevent rolling on relatively flat grades, they may be OK. They are in no way an “emergency” brake and don’t even qualify as a parking brake IMO.


So to be clear, you are saying you really like the IPSCO calipers and they function well and the cart Wilwood Calipers were junk for using them on a vehicle... Is that correct?
quote:
Originally posted by Z06 Pantera:
quote:
Yes, I have the IPSCO made units on my car. They work great. They do cost more than the Wilwood spot calipers but you get what you pay for. It is why I took interest in Jack’s post. I think he is the first I’ve ever heard express any degree of satisfaction with them. Folks on the GT40 forum have nothing good to say about them either and I can see why. Besides the fact they didn’t work, I felt the quality was poor. I literally through the ones I had away and felt they were virtually useless mass with the inability to hold my car on any significant incline. Although my opinion of Wilwood products is generally high (I have their calipers, rotors, master cylinders, etc), I think this is a matter of intended use. The subject calipers don’t belong on cars.

I suppose it depends upon you’re expectation for them. If you want something to prevent rolling on relatively flat grades, they may be OK. They are in no way an “emergency” brake and don’t even qualify as a parking brake IMO.


So to be clear, you are saying you really like the IPSCO calipers and they function well and the cart Wilwood Calipers were junk for using them on a vehicle... Is that correct?


Yes, that's been my experience.

Best,
K
Post
×
×
×
×
Link copied to your clipboard.
×