Cobra brakes for Granada/70-73 Mustang DISK spindles

[Shaun]

So I just put together a kit for the 68-73 Mustang disk spindle using SN95 calipers, modified anchors, 65-73 5-lug drum hubs and the 13" high hat offset rotor I use:

Link

Seeing as how the Granada spindle is not that much different, this kit will also fit those spindles. Just the upper bracket hole will need to be drilled out in the spindle from 1/2" to 9/16ths.

Putting this kit together got me thinking. Lots of people like my Cobra brackets for drum spindles. Who would be interested in the same concept for 68-73 Mustang DISK and Granada/Versailles spindles? I often get asked at the shows I do what I have for the Granada spindle. Folks can be funny sometimes though, sure they are interested until they hear the price. I want to be upfront about the estimated cost before even pursuing it. I don't want to end up with a lot of money tied up in a pile of slow moving brackets! I'm sure you can appreciate that. :thumbsup:

I figured I'd ask here and get some rough numbers first.

The kit would use a similar bracket to the one pictured above, just the offset would be different to accomodate the shallower hat of the Cobra rotor. The kit above and my planned kit for the Cobra rotor will use a modified anchor (the yellow zinc piece). I'm estimating a selling price for the SN95 Cobra rotor bracket kit of around $299. This would get you the spindle mounting brackets, modified caliper anchors, hub-centric adapter shims and install hardware. Just like the kit for the drum spindle, you'd need to add calipers, pads, hubs, bearings, seals, hoses etc.


April 23rd, 2009
I've been working away on this project and just finalized the engineering.

As usual we way over enginered the product. We plugged in a 3800lb car with 275/45/17 rubber pulling 1.2G's decel with 80% of the braking being provided by the front wheels. As you can see these figures are very generous for the average vintage Mustang. We still acheived a safety factor of almost 2:1.

The longer bosses don't create an issue so I'm ready to start manufacturing. I still put the retail price at approx. $299 for the brackets, modified Cobra anchors, bolts etc. and rotor centering shims. Is this too much money? Should I not bother? Who is interested?

 

[Fast68back]

I guess there are two ways of looking at it. The folks that did the granada swaps early on did it because it was essentially the only game in town. Not many companies offered aftermarket Discs for early Mustangs. Lately, they last few years, most have done the Granada swap because its the cheap way to go.

So, you have to sides to your target market, the guys looking for an affordable upgrade to what they did years ago and the guys looking for a CHEAP alternative/upgrade. I think you have to be very careful with your pricepoint.

Unfortunately, its not cheap to bring new stuff to the market. R&D costs are high. Just my $.02


Personally, I think its a cool product and wish you luck with it.

 

[Shaun]

So, you have to sides to your target market, the guys looking for an affordable upgrade to what they did years ago and the guys looking for a CHEAP alternative/upgrade. I think you have to be very careful with your pricepoint.

That is what I'm banking on. The SN95 Cobra swap is a pretty cheap way to put together your own kit, the missing link has been the bracket to mount to the spindles.

For the guys with Granada spindles that don't want to go back to the Mustang drum spindle AND don't have the resources to put together their own kit I'll have the full kit.

I keep getting asked at shows so there is some interest.

 

[joesgt281]

Shaun,
Unfortunately I just did my swap using somebody else's kit otherwise I would have been interested in maintaining my 70 disk spindles.
The other kit requires the swap to the drum spindles which I believe are not as stout as the disk ones so I feel like I gave up something going that direction.
Good luck with the new setup.

 

[Fast68back]

You should work out a deal with Roush and Saleen and buy all their takeoff stuff. There is also Quantum performance in Texas that is a Shelby mod center.

 

[Shaun]

Shaun,
Unfortunately I just did my swap using somebody else's kit otherwise I would have been interested in maintaining my 70 disk spindles.
The other kit requires the swap to the drum spindles which I believe are not as stout as the disk ones so I feel like I gave up something going that direction.
Good luck with the new setup.

I already have the brackets for the swap with drum spindles - http://www.streetortrack.com/13-Cobra-f ... 23991.html

 

[Shaun]

You should work out a deal with Roush and Saleen and buy all their takeoff stuff. There is also Quantum performance in Texas that is a Shelby mod center.

Good thought, Saleen are just down the road from me... They have the S197 take off stuff, I'm working with the SN95 Cobra stuff right now though.

 

[Midlife]

Didn't Saleen go under after Steve Saleen sold it, and now Steve Saleen is working under another name/brand?

 

[joesgt281]

I already have the brackets for the swap with drum spindles - http://www.streetortrack.com/13-Cobra-f ... 23991.html

yeah I had already got my other kit before you came out with that.

 

[tarafied1]

I guess there are two ways of looking at it. The folks that did the granada swaps early on did it because it was essentially the only game in town. Not many companies offered aftermarket Discs for early Mustangs....

Speaking as a guy who did the Granada spindle swap back in the early 90's, it was exactly why Fast68back said. Original discs were pricey and the Granada stuff was cheap and easy. As I recall, there wasn't aftermarket stuff widely avaialble if at all. In fact I even did the Versailles 9" rear with discs for the same reason.
The price is probably fair but by the time you total all that you need to buy it is an expensive conversion. Right now I'd love to upgrade but I don't race the car and the GVM stuff has been working fine for me for nearly 20 years. GVM rotors and calipers are still available at parts stores too for pretty cheap (I just bought a rear rotor for $35 at NAPA). It's a great idea and if it were available it may be something I would consider in the future, especially if you packaged everthing together. I know people get nervous about messing with the brakes. If you had all the right parts identified and available together it would be more attractive. Good Luck!

 

[Fast68back]

Has anyone priced a rebuilt caliper for the late model mustang? Since they are PBR calipers. I'm sure wrecked GTs are easy enough to find in the salvage yards.

 

[Sluggo]

Has anyone priced a rebuilt caliper for the late model mustang? Since they are PBR calipers. I'm sure wrecked GTs are easy enough to find in the salvage yards.

PBR....Pabst Blue Ribbon?

 

[Fast68back]

PBR....Pabst Blue Ribbon?

I dont know, thats the name of the company...Australian, IIRC

http://www.pbr.com.au/products/original/brakecalipers.shtml

 

[Shaun]

Speaking as a guy who did the Granada spindle swap back in the early 90's, it was exactly why Fast68back said. Original discs were pricey and the Granada stuff was cheap and easy. As I recall, there wasn't aftermarket stuff widely avaialble if at all. In fact I even did the Versailles 9" rear with discs for the same reason.
The price is probably fair but by the time you total all that you need to buy it is an expensive conversion. Right now I'd love to upgrade but I don't race the car and the GVM stuff has been working fine for me for nearly 20 years. GVM rotors and calipers are still available at parts stores too for pretty cheap (I just bought a rear rotor for $35 at NAPA). It's a great idea and if it were available it may be something I would consider in the future, especially if you packaged everthing together. I know people get nervous about messing with the brakes. If you had all the right parts identified and available together it would be more attractive. Good Luck!

And a 13" Cobra rotor can be had for $40ea. All you need to add to your drum hub is calipers, pads and hoses. The Granada conversion still works ok unless you step up to 17" wheels which alot of people are doing and is what this kit is aimed toward.

I do have the complete kits available. Like you mentioned, I have 2 types of customers. Those who like everything needed in a box with instructions and those guys that don't mind pieceing together a few components themselves to save a few $'s...

 

[tarafied1]

Couple questions:

What difference does wheel diameter make? If total tire diameter is the same the lever hasn't changed, am I missing something?

What would a typical 13" rotor conversion cost? I see aftermarket kits like Total Control sells from $1200 up for 13" rotor conversions... with your $300 brackets could I upgrade for less using Cobra parts? Hubs, rotors, hoses, etc. everything?

Back in the day I paid $75 for complete Granada spindles, all I needed was hoses and tie rod ends. Of course I've since replaced the rotors, pads and calipers but that's still pretty cheap. My buddy recently bought complete spindles (as I did) for $175 to put on his car so they are still out there.

I agree a 13" rotors and Cobra calipers are going to be better than a 10" Granada rotor and single piston caliper but will I notice the $1000+ upgrade on the street?

 

[Shaun]

Couple questions:

What difference does wheel diameter make? If total tire diameter is the same the lever hasn't changed, am I missing something?

Wheel dia. plays a huge role in stopping distances and where the lever is. In the case of keeping the overall dia. the same (increasing rim dia. but downsizing tire aspect ratio) then the larger rotor dia. would add more heat sink. Bigger wheels typically weigh more so with more weight rotating and needing to be stopped, that will create more heat. The other reason is purely cosmetic. Big wheels need big rotors behind them to fill them up.

What would a typical 13" rotor conversion cost? I see aftermarket kits like Total Control sells from $1200 up for 13" rotor conversions... with your $300 brackets could I upgrade for less using Cobra parts? Hubs, rotors, hoses, etc. everything?

I have full kits starting at $1099 using my higer hat offset rotor - http://www.streetortrack.com/What-wheel ... tml. $1099 gets you every single piece right down to banjo bolts, crush washers, braided DOT hoses, rotors, pads, calipers, bolts, nuts, hubs, bearings, seals, dust caps etc. The bracket only kits rely on you using SN95 Cobra rotors and buying/sourcing the bearings, hubs etc.

Back in the day I paid $75 for complete Granada spindles, all I needed was hoses and tie rod ends. Of course I've since replaced the rotors, pads and calipers but that's still pretty cheap. My buddy recently bought complete spindles (as I did) for $175 to put on his car so they are still out there.

$175 for the complete Granada setup is a good deal. What I've tried (and have acheived) is to take the later model Mustang technology and package it onto our early cars. If a 3600lb SN95 Cobra stopped great on these brakes, then our 3000lb cars will stop as good if not better.

I agree a 13" rotors and Cobra calipers are going to be better than a 10" Granada rotor and single piston caliper but will I notice the $1000+ upgrade on the street?

I'm going to say yes. Before I started these 13" brake projects I was running around on a SSBC kit with Kelsey Hayes 4 piston calipers. My first Cobra caliper kit uses a 11.25" dia. rotor with the SN95 Cobra calipers for 15" wheels and it blew the SSBC kits performance out of the water! http://www.streetortrack.com/Street-or- ... html We've since developed a bunch of the 13" rotor kits and I've measured 0.83G's deceleration in my 66 with street tires and stock rear drums.

My view is brakes are not optional. 40 years ago all the cars had crappy brakes and longer stopping distances. Now even a Ford Focus can outbrake most of us. The more brake the better!

 

[tarafied1]

Thank you for the in depth answer, I will reconsider my future upgrade priorities. So to answer your intial question, I guess I am going to need the braket for Granada spindles.

 

[Shaun]

Thank you for the in depth answer, I will reconsider my future upgrade priorities. So to answer your intial question, I guess I am going to need the braket for Granada spindles.

Thank you for the feedback! I'll add more to this post when the project moves along.

Anybody else have any input on this idea?

 

[tarafied1]

Not sure how you would go about doing this but I might suggest publishing and/or promoting the benifits of bigger brakes. I know they have those devices that you can use to measure G force, accelleration and braking in the car. Maybe a test of before and after? If I can get access to one and afford the upgrade I will happily volunteer the before and after data of switching from 10" Granada brakes to 13" Cobra Street or Track LLC brakes. I'm awaiting the potential bad news of no company bonus this year, that has been my "play" money and usaully significant. Our bonus usally comes in late June but our company is in bad shape right now so I'm not expecting much...

 

[Shaun]

I have deceleration G-force data with the kits installed, I've just been too excited with every install to actually go out and get the data before the install!

The benefits are pretty obvious though. Larger rotor for greater heat sink, better/cheaper pad choice, late model components are easily available at your local parts store etc...