Ordered My Disc Brake Conversion Kit

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68 CUDA FORMULA S

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So I have gone and ordered my disc brake conversion kit from Pirate Jack. Kit number DBK6272A-40 and have also ordered from them the duel master cylinder number MC5621. I have also ordered my duel master cylinder conversion brake lines and distribution block from in line tube. The Pirate Jack master cylinder comes equipped with the internal residual valve for the rear brakes, and In Line Tube states that I will not have to change any factory brake line fittings or add any adapters to connect my existing brake lines to there block. I should have everything next week some time and after everything is installed I will tell you how it went.
Bob
 
So I have gone and ordered my disc brake conversion kit from Pirate Jack. Kit number DBK6272A-40 and have also ordered from them the duel master cylinder number MC5621. I have also ordered my duel master cylinder conversion brake lines and distribution block from in line tube. The Pirate Jack master cylinder comes equipped with the internal residual valve for the rear brakes, and In Line Tube states that I will not have to change any factory brake line fittings or add any adapters to connect my existing brake lines to there block. I should have everything next week some time and after everything is installed I will tell you how it went.
Bob


:popcorn::popcorn::popcorn:
 
Not knowing the caliper diameters or throw of the brake-pedal, my first guess is that the MC is going to be too large in diameter (1.125").
 
My question is where do they get the rotors and if you could put a LBP rotor on the spindles to upgrade later down the road.
 
The pirate jack kit is just a 73+ BBP Mopar disk conversion with the rotors drilled for the SBP.

Which is fine, except the hub bore is larger than will fit most OE SBP rims, and of course the track width increases as well. They also list the lug size as 1/2", so, not the standard 7/16" SBP studs either. So, there's a decent chance you'll have to buy new rims anyway if you've got SBP drums with stock wheels now.

There's also the issue of buying rotors should you ever need to replace them. If pirate jack is still around great, if not you'll have to buy 73+ rotors and have the 5x4 pattern added.
 
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My question is where do they get the rotors and if you could put a LBP rotor on the spindles to upgrade later down the road.

Who knows where they get the rotors. They probably contacted one of the overseas manufacturers direct and ordered a run of the BBP rotors drilled with the 5x4" pattern, or ordered the rotors as blanks and are adding the pattern themselves. Order enough product and this is possible. Looks like they sell the rotors by themselves too, so you could order replacements if you needed. Again, assuming pirate jack is still around. I'm assuming they ordered the rotors blank or with the 5x4" pattern because the pictures they show don't show a dual set of patterns. But maybe the real rotors have both patterns, I haven't seen the rotors in person.

And yes, you could just buy a set of the 73+ rotors and upgrade to the 5x4.5" pattern later. Everything shown in the Pirate Jack kit is just reproduction 73+ mopar parts, they just add the ball joint adaptors so you can use them with SBJ UCA's. And the rotors with the 5x4" pattern.

On that note, you could get everything but the generic brake booster and 5x4" pattern on the rotors from Dr. Diff.
 
I went with ECI kit years ago for my front brakes with late model mopar master cylinder. Went with the drilled rotors. Might be cheesy but my cuda has great brakes. I had to nail them pretty hard not long ago after doing a burnout. The car was side ways ... caught...and I lost control of it. If I had drum brakes I would have hit the ditch and might have rolled over. Glad no body was around to see it. lol

I'm not just saying that they are great because i have them on my car... they actally work good. I have a line lock on the front and it will hold the car that has big wide tires on the back.
Changed the front from small bolt pattern to large as well.

ECI Disc Brake Conversion Kits - Chrysler Products

EDIT: OP wants to stay small bolt pattern... ECI is only large bolt pattern.

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Well you guys will just have to stay tuned. They claim that there kit is bolt on and go and that everything will fit properly. I tried to deal with Cass over at Dr. Diff but they only offered the LBP kit and I do not want to switch my rims. When I get it all put together and if everything works like they say it will I will let you know. As far as ever having to replace the rotors I don't think I will ever put that many miles on it, I have been driving it for a little over four years now and still have not even put 800 miles on it. If it's pictures you are looking for go to the Pirate Jack web site and they have pictures of the whole set up. They also claim that I can use my factory rally wheels.
Bob
 
Everything will bolt on, I've got no doubts about that. Pretty much everything in that kit is reproduction 73+ mopar disk parts. I've seen the pictures, I've looked into this particular kit up a couple times because of people asking about it.

It's just a 73+ disk brake set up that has had the later BBP style rotors modified to have the 5x4" pattern. All the same considerations that apply to doing the 73+ disk swap still apply except for changing to the 5x4.5" pattern, but, even then, there are still considerations because of the larger hub and studs.

The only question will be if the rims you've got now will fit over the larger diameter of the hubs, if the 1/2" studs will work with those rims, and whether or not your tires will still clear the fenders with the added track width from using the 73+ disk set up.
 
Maybe if the special order the rotors from over seas than they get the hub a little smaller also to fit the other rims. Im curious to see the outcome. I have a scarebird set on my dart and its coming time for new rotors which set me back about $150 by time its all said and done.
 
Maybe if the special order the rotors from over seas than they get the hub a little smaller also to fit the other rims. Im curious to see the outcome. I have a scarebird set on my dart and its coming time for new rotors which set me back about $150 by time its all said and done.

My guess is the extent of the special order is getting the
rotors blank and then adding their own bolt pattern. But I suppose it's possible.

The thing is, the hubs can't be a lot smaller. The hubs house the wheel bearings, so, you can't just make them a whole bunch smaller in diameter without stating to compromise the strength of the hub. That's not saying you can't make them a little smaller, but there's definitely a limit.
 
You guys will know what fits with no problem and what if any needs to be modified. I will take pictures as I go along and post as I go. If all goes well then you know if it's a good kit to get or not, one thing for sure the price is right, lets see about the product. Stay tuned.
Bob
 
The price is about the same as a 73+ disk conversion from Dr Diff. Which makes sense, because it's literally just a 73+ disk kit with a different bolt pattern drilled on the rotors, unless maybe they're turning the hub diameter down too.

The booster cost is the biggest price difference, but that's because Pirate Jack is selling a generic $75 booster where Dr. diff is selling a fairly accurate Bendix style reproduction of the original.

But I am looking forward to seeing what they're doing with the rotors, that will be the biggest consideration for most folks. If you can't keep the OE wheels because of the hub diameter you might as well just use the standard version of the 73+ disks and go BBP.
 
Brakes should be here either tomorrow or Friday so I had time to get a little work done today. PST 1.03 torsion bars and stiffing plates showed up yesterday so I got the plates welded on, cleaned up the control arms, wanted them black. Tomorrow I will press in the new lower control arm bushings and install the new torsion bars, got some new strut bar bushings also. If all goes well then it's brake time.

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The LCA's look good!

Yeah it's really not that bad to add the stiffening plates, just set the LCA's up in a vise to set the clearance on the torsion bar lever and then weld the plates on. Some of them need to have the bump stop plate welds cut on one side if the clearance on the arm is way off, like Jim Lusk did in his video. But not all of them are that far off.

I add an extra strap to mine when I do the reinforcing plate, keeps the clearance on the torsion bar adjusting lever nice and tight.

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Looks good, I pressed in my pivot shaft bushings today and everything went well. I hope to get started tomorrow on putting everything back together. I still have some quality driving time left.

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My Pirate Jack brakes showed up today also, one day ahead of schedule. They came in three boxes, two big boxes and one small box. The master cylinder was in the small box, looks pretty darn good to me. Then all the brake conversion parts were in the two big boxes. I also took some good pictures of the rotors as requested, my stock 7/16-20 SBP lug nuts fit the wheel studs just fine, and my stock rally wheels fit the hub on the rotor just fine also. Look at all the pictures what you see is what I got. I will not know about the caliper clearance until everything is together so give me a few days and I will show you as I go along. So far no disappointments this kit looks great. I still need to drive over to in line tube tomorrow and pick up my duel master cylinder brake lines and the distribution block. Enjoy, I am.
Bob

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Forgot to show you the master cylinder. I am going with the manual brake set up for right now and if I choose to go power latter I can still use the same M/C

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Interesting.

Still not 100% sure if they're having rotors cast that way or machining blanks for their kit, but either way they're doing a lot of work to make the 5x4" pattern work on those rotors. Kind of looks like they're having them cast that way. They added the scallops into the backside of the hub to clear the studs with the 5x4" pattern. And the outer hub is definitely being turned down or cast thinner, that outer hub/center register area is quite a bit thinner than on the stock rotors.

So the good news is the claims they're making are probably accurate, with the hub diameter being narrower they should fit a lot of the SBP wheels. And they're 7/16" too, so again they should fit most stock wheels. The track width is still changing (wider) so you'll have to pay attention to your tire to fender clearance still.

The bad news is, that hub isn't as strong as the OE hubs. That thinner outer wall that supports the outer wheel bearing isn't as strong. And those scallops into the inner part of the hub where the inner bearing rides weaken it there too. Now, from the factory those hubs are built with a substantial safety factor built in, so, it's probably ok. But hopefully someone actually did the math on that and determined the strength of that modified hub and decided it was sufficient, rather than just modifying the OE hub so it would work for their kit.
 
I can't answer that, maybe when another member decides to give this kit a try and has the stock steel wheels they will chime in. As for me, when it comes time to put the rally's on and give it a ride I will check fender clearance and make sure everything is a go.
 
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