FinoCJ
Well Oiled
I completed a front disc brake conversion using the R&P 1/4 ton kit....And I am absolutely satisfied with the set-up. I put it on the D25 in my 58 wagon, but it would work on D25/D27/D30/D44 and on CJs, wagon, pick-ups etc. I am running this with an aftermarket Willwood MC (2 circuit), but no power/vacuum assist - its one of the two options for replacing the OEM single circuit MC and I ran it with the OEM drums for a number of years- and the stopping power is markedly improved. I posted a few progress points along the way in the 58 build thread, but seemed it might be useful to post a finalized thread with list of items etc for anyone looking to do this? If mods prefer, I can just add this to my build thread - just sometimes harder to get 'final' info as build threads sometimes wander along an 'indirect' path to completion with lots of side thoughts etc....
Without too much detail, this set-up is basically GM 1/4 ton brakes from something like a 1990 S10 pickup/blazer. All routes have some advantages and disadvantages - I went this routes as I prefer the option of outboard rotors that slip on/off over the hub as opposed to the GM 1/2 ton kit where the rotors are pressed on the backside of the hub. This makes servicing the brakes quite a bit easier IMO. Also, this set-up doesn't require any additional clearance (read grinding) between the knuckle and caliper. Also, as the rotors are outboard, there is no concern about needing to machine the back side of the hub or buy new hubs (I was expecting to find the backside of the hubs on my D25 would not have the machined flat surface when I pressed off the drums, but they were - so not sure if they have been replaced at some point, or when the hubs started coming that way OEM?). Although most all the parts for this conversion are available from basic auto parts stores, the one critical part that must be purchased specifically is the caliper bracket....this is what makes this the 'R&P' conversion as this bracket is their piece.
The GM 1/2 ton route is certainly tried and true - all parts, including the caliper bracket, can be found at basic auto parts stores etc, and is the make-up of most aftermarket conversion kits. Depending on how 'big' of a tire or rig you choose to build, its worth considering as well. R&P recommends the 1/4 ton kit up to 33 inch tires - beyond that, its probably 1/2 ton category. For me, running OEM D25, I don't have to worry about going any bigger than 32s or so, and figure brakes good enough for a 90s S-10 going 70mph is good enough for my wagon. Also, if it didn't seem like enough stopping power, I could always swap it over to the CJ....after driving this around for a bit, the braking power has be GREAT on my 58 wagon with sbc350 running 30s.
Just to note, a 3rd option for disc brakes is the Metcalf/Geo Tracker/Sidekick conversion - other than a precursory look, I didn't research this a lot - but I did notice the caliper brackets are 2-piece. And there is of course, the newest and biggest conversion from Jeepsterman - but that wouldn't work with my 15" aftermarket wheels. I am sure all options are very functional, nice improvement over the OEM drums, and which you choose comes down to details of what the owner prefers and intends for his rig. And finally, if you just aren't into pieces items together yourself, you can get complete kits of both the 1/2 and 1/4 ton set-ups from Sam and Parts Dude - including all the way to new hubs with new wheel bearings and the rotor already pressed on etc....
Parts list for R&P 1/4 ton disc conversion:
So, here are the final parts and pieces I found useful to complete this project.
Although I ordered this from Rich at his new venture called R&P Early Jeeps, I assume its the same as the original R&P 4wd set-up....probably depending on what you order from Rich, it seems people get more or less parts, depending on how 'complete' of a kit they want. But the basic idea is that the custom caliper brackets are the key part to get from R&P, and the rest you can get from FLAPS (Rich includes some of this parts list with his calipers, but some stuff is also vehicle specific depending on choice of wheels and whatnot):
1) caliper brackets - custom from R&P
2) rotors - I got mine along with the caliper brackets from Rich, so not sure exactly what they come from. I think they are from something like a 1990 Suzuki Samarai - the typical GM s-10 rotors don't have large enough center bore to fit over Jeep hubs)
https://www.rockauto.com/en/catalog/suzuki,1990,samurai,1.3l+l4,1271179,brake+&+wheel+hub,rotor,1896
3) Calipers - I used Carquest 18-4129 (left) and 18-4128 (right)
4) Brake Pads - D154 (organic - only found these through O-riellys)
5) Brake Lines - Summit Racing 230910 - these worked out really well as they work with 7/16 in. banjo bolt at the caliper end and female 3/8 in -24 inverted flare on the other (to connect to my traditional hard line). 15.75 in. length seems really good and is a bit shorter than many of the other options, so less excess hose to deal with.
6) Wheel studs - Dorman 610-260....I still had the OEM style wheel studs and Wagner brake drums pressed on the back of the hub....I needed a longer wheel stud to work going through the rotor and using a thicker modern mag wheel with acorn nut. If still using a thin steel wheel or shanked lug nuts, maybe not necessary....These Dormans have a very short section of knurl as I was initially concerned the knurl could protrude through the hub and engage into the outboard rotor, but the rotor was counterbored so this wasn't as big of an issue as I was thinking.
7) Knuckle Studs...3/8" - 24 x 1.5" I did the buttonhead knuckle stud conversion at the same time, and as the caliper bracket is 1/4' thick, I went with a 1/4" longer buttonhead to 1.5" length bolt to ensure it would go through the caliper bracket and leave enough thread to nut off properly. I used metal lock nuts on mine, but there was enough thread you could use a standard lock washer if preferred.....
Without too much detail, this set-up is basically GM 1/4 ton brakes from something like a 1990 S10 pickup/blazer. All routes have some advantages and disadvantages - I went this routes as I prefer the option of outboard rotors that slip on/off over the hub as opposed to the GM 1/2 ton kit where the rotors are pressed on the backside of the hub. This makes servicing the brakes quite a bit easier IMO. Also, this set-up doesn't require any additional clearance (read grinding) between the knuckle and caliper. Also, as the rotors are outboard, there is no concern about needing to machine the back side of the hub or buy new hubs (I was expecting to find the backside of the hubs on my D25 would not have the machined flat surface when I pressed off the drums, but they were - so not sure if they have been replaced at some point, or when the hubs started coming that way OEM?). Although most all the parts for this conversion are available from basic auto parts stores, the one critical part that must be purchased specifically is the caliper bracket....this is what makes this the 'R&P' conversion as this bracket is their piece.
The GM 1/2 ton route is certainly tried and true - all parts, including the caliper bracket, can be found at basic auto parts stores etc, and is the make-up of most aftermarket conversion kits. Depending on how 'big' of a tire or rig you choose to build, its worth considering as well. R&P recommends the 1/4 ton kit up to 33 inch tires - beyond that, its probably 1/2 ton category. For me, running OEM D25, I don't have to worry about going any bigger than 32s or so, and figure brakes good enough for a 90s S-10 going 70mph is good enough for my wagon. Also, if it didn't seem like enough stopping power, I could always swap it over to the CJ....after driving this around for a bit, the braking power has be GREAT on my 58 wagon with sbc350 running 30s.
Just to note, a 3rd option for disc brakes is the Metcalf/Geo Tracker/Sidekick conversion - other than a precursory look, I didn't research this a lot - but I did notice the caliper brackets are 2-piece. And there is of course, the newest and biggest conversion from Jeepsterman - but that wouldn't work with my 15" aftermarket wheels. I am sure all options are very functional, nice improvement over the OEM drums, and which you choose comes down to details of what the owner prefers and intends for his rig. And finally, if you just aren't into pieces items together yourself, you can get complete kits of both the 1/2 and 1/4 ton set-ups from Sam and Parts Dude - including all the way to new hubs with new wheel bearings and the rotor already pressed on etc....
Parts list for R&P 1/4 ton disc conversion:
So, here are the final parts and pieces I found useful to complete this project.
Although I ordered this from Rich at his new venture called R&P Early Jeeps, I assume its the same as the original R&P 4wd set-up....probably depending on what you order from Rich, it seems people get more or less parts, depending on how 'complete' of a kit they want. But the basic idea is that the custom caliper brackets are the key part to get from R&P, and the rest you can get from FLAPS (Rich includes some of this parts list with his calipers, but some stuff is also vehicle specific depending on choice of wheels and whatnot):
1) caliper brackets - custom from R&P
2) rotors - I got mine along with the caliper brackets from Rich, so not sure exactly what they come from. I think they are from something like a 1990 Suzuki Samarai - the typical GM s-10 rotors don't have large enough center bore to fit over Jeep hubs)
https://www.rockauto.com/en/catalog/suzuki,1990,samurai,1.3l+l4,1271179,brake+&+wheel+hub,rotor,1896
3) Calipers - I used Carquest 18-4129 (left) and 18-4128 (right)
4) Brake Pads - D154 (organic - only found these through O-riellys)
5) Brake Lines - Summit Racing 230910 - these worked out really well as they work with 7/16 in. banjo bolt at the caliper end and female 3/8 in -24 inverted flare on the other (to connect to my traditional hard line). 15.75 in. length seems really good and is a bit shorter than many of the other options, so less excess hose to deal with.
6) Wheel studs - Dorman 610-260....I still had the OEM style wheel studs and Wagner brake drums pressed on the back of the hub....I needed a longer wheel stud to work going through the rotor and using a thicker modern mag wheel with acorn nut. If still using a thin steel wheel or shanked lug nuts, maybe not necessary....These Dormans have a very short section of knurl as I was initially concerned the knurl could protrude through the hub and engage into the outboard rotor, but the rotor was counterbored so this wasn't as big of an issue as I was thinking.
7) Knuckle Studs...3/8" - 24 x 1.5" I did the buttonhead knuckle stud conversion at the same time, and as the caliper bracket is 1/4' thick, I went with a 1/4" longer buttonhead to 1.5" length bolt to ensure it would go through the caliper bracket and leave enough thread to nut off properly. I used metal lock nuts on mine, but there was enough thread you could use a standard lock washer if preferred.....
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