My own JK 'Big Brake' research:
- Thread starter Majik
- Start date
Majik
Member
Yes and no. I mocked up the brackets out of lexan. The mock up was a great idea, too, because I found one key hitch in this build. To some people, like myself, they are gonna say "no big deal", but others are gonna probably say "that is too much for me to deal with". It appears that to mount these calipers and perfectly align them with the rotors, ONE of the factory caliper mounting holes on the knuckle needs to be slotted about a quarter of an inch. I have a new set of Reid Racing knuckles that is going on with upgraded ball joints, so it's not an issue for me, but for alot, it might be a deal breaker. The reason has to do with the height of the built-in caliper mount on this particular caliper. It actually is a tiny bit too tall. So... I am going to take one of my factory knuckles to the machine shop, put it in an end mill and slot one of the holes, bring it home, and see how it works. It will take the shop no time at all to do, but I know alot of people are going to say "I'm not taking off my knuckles to do this...I want a pure bolt-on upgrade". And I totally understand that perspective. I would prefer it that way, too. If it works (and I suspect it will), I will bring the Reid's over and perform the same mod.
And to answer in advance some replies I know I'm going to get from this: 1. yes, the iron knuckle is PLENTY thick at the area I'm going to slot it. Nearly a full inch thick. 2. The tiny space in this 'slot' that will be open next to the factory caliper mount bolt will be filled with a small steel crescent-shaped dowel pin. This will lock the bolt and prevent any chance at sliding. (Even though sliding is nearly impossible because the other caliper mount bolt hole will be fixed, not slotted. 3. The Reid knuckles are even thicker in this area 4. I'm still researching other alternatives, but I think this is going to be the only way to make it work.
I hope everyone can picture what I'm describing. It's just like the slotted adjustment that you have on a mounting bracket for an engine accessory, like an alternator, on an engine that doesn't use serpentine belts. The alternator has a fixed pivot bolt, and then one bolt in a slot that can pivot back and forth and be tightened down to lock the alternator in place with the belt in tension. Except the slot I'm speaking of is only an extra 1/4" added to the standard bolt hole. That's all I need. And with the 'dowel pin' (for lack of a better term) used to fill the empty portion of the slot, the caliper won't be able to move. The rest of the mounting adapter is steel plate to provide the right offset and align the caliper with the rotor perfectly.
Everyone following? I know that alot of people are gonna be bummed by this requirement. To fit a 14+ inch rotor in a 17" rim, using OEM parts, I knew there had to be some minor issue to address somewhere... In fact, I'm kinda proud because both Wilwood's ~$2000 front brake kit and Brembo's ~$4400 front brake kit both state they require an 18" rim. That rim requirement would turn alot of people away, I would imagine. It appears that I will be able to make this setup work with 17" rims, with the same (actually a touch bigger) rotor size as the big companies and calipers with the same piston sizing. Oh, and I don't think we are even going to have to touch the master cylinder! Forgot to mention that
I will keep you updated...
Majik
Member
BTW, for those who are still game and aren't turned away by the knuckle hole issue I discussed above, think of the quick jaunt to your machine shop with steering knuckles in hand as a good time to upgrade your ball joints. :yup: Throw some $200 Synergy's or your favorite other brand in while you have the knuckles off and have a double-upgrade (brakes AND ball joints)! .... or even weld in a few C-gussets while it's all off!!
BTW, for those who don't know, or have little experience, it takes only about 10 minutes to have the hub off down to the knuckle and another 10 minutes to press the ball joints out. So long as you have the right tools already laid out. Just trying to help convince everyone that they CAN do this OK, most can. OK, most mechanically-inclined can... OK, I'll just let you decide...
BTW, for those who don't know, or have little experience, it takes only about 10 minutes to have the hub off down to the knuckle and another 10 minutes to press the ball joints out. So long as you have the right tools already laid out. Just trying to help convince everyone that they CAN do this
OK, most can. OK, most mechanically-inclined can... OK, I'll just let you decide... 
Rebel JK
New member
BTW, for those who are still game and aren't turned away by the knuckle hole issue I discussed above, think of the quick jaunt to your machine shop with steering knuckles in hand as a good time to upgrade your ball joints. :yup: Throw some $200 Synergy's or your favorite other brand in while you have the knuckles off and have a double-upgrade (brakes AND ball joints)! .... or even weld in a few C-gussets while it's all off!!
BTW, for those who don't know, or have little experience, it takes only about 10 minutes to have the hub off down to the knuckle and another 10 minutes to press the ball joints out. So long as you have the right tools already laid out. Just trying to help convince everyone that they CAN do this
The knuckle hole machining seems like a small price/detail when you look at the end result. I'm thinking that for the guys out there that have already invested in some real performance mods, a little machine work to improve a vital system, won't scare too many away. I am following closely and have added this to my upgrade list, now that it will be in my price range!
Thanks for all the info, looking forward to following along.
Not to hijack, but would also love to hear more about prime8's DYI hydro steering build on a separate thread!
Majik
Member
So glad that someone chimed in with a reply! I was afraid that I scared EVERYONE off! Going to take the knuckle to the machine shop tomorrow and make the slot. Then I can finalize the dimensions of the adapter bracket. Wish me luck! :standing wave:
Pm'ed ya. . I have no problem modifying anything to make it better.
. I have no problem modifying anything to make it better.Thanks!!
you gave more than enough,your thread is truly inspiring.
I'm half way reading through this ,and i can tell you that i'm sold whatever final outcome you come up with.
Oustanding Job my friend.:thumb::thumb::thumb:
Rebel JK
New member
I Sure I'm not only speaking for myself, but I'm really looking forward to seeing what you come up with. With your approach, I don't think youll need much luck!
bluewave
Member
the only thing I could add to this is, why don't you have the machine shop plug the original hole drill and tap as needed.
Thanks for all the time and effort and cost you have put in to this
Majik
Member
Good thought. I considered just fill welding that unused part of the slot myself. No tapping needed. It's just a hole. The bolt goes through the knuckle and the caliper bracket is threaded. But good thought about letting the shop do it... just wondering what the extra cost is for them seeing it's cast iron and probably a bit more complicated as far as welding.
Not to mention ruining that gorgeous orange Reid paint with weld spatter! (kidding!!) BTW... why the hell did they pick pale orange? :idontknow:
bluewave
Member
here is my feelings, somebody correct me if Im wrong or out of line.
1. my experiences as a certified welding inspector has taught me that if you can get rid of any potential momentum it would stop shearing, ie if the roll pin fell out.
2. ductile iron is weldable with pre heat and slow cool down. I would use a flux core or normal er-70s6 wire to weld it with. then drill it
3. since it has no warranty on the part anyways wouldn't it be worth the chance to try?
Majik
Member
Part of the reason, though, that I suggested the pin is to keep things cheap and simple. I still want this brake upgrade to be affordable to all and I already felt bad enough about having to do a minor mod to the knuckle. I don't want the average joe to end up having to spend $500 in labor to bring their knuckles somewhere to have them plug welded (correctly, with preheating, etc) and then precisely bored for the new mounting hole. The pin was just a simple solution after a minor 2 minute task to slot the hole on an end mill. Of course, the pin could receive a simple tack weld on each end to secure it...
I love your solution. I just want to keep in mind those that might want to do this mod but not have a certified welder in their back pocket
Majik
Member
Love the avatar... and thanks for the kind words :blush:
Majik
Member
Just got the machined Reid knuckle back from the shop. Just my opportunity to send a 'kudos' out to the guys at American Precision Machine shop in Abilene. So awesome and even gave my son the tour of the shop... and no. I still paid for the work. I'm not getting free labor for mentioning them. They just simply deserve a shout for being an honest, quailty shop. :thumb: Everyone nowadays hears about it if you are not satisfied, but hardly anyone ever gets a thank you for just being polite and professional, not to mention good at their job!
So... on to mounting and adapter machining!
So... on to mounting and adapter machining!
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Getting closer.
Jeep2.0
New member
Majik, I couldn't quite tell from the photos: is there enough room inside the rim for stick-on wheel balancing weights? Most of my last 5 rigs have used them vs the pound-ons, especially with aluminum rims, beadlocks, etc.
As for the knuckle mod: I don't see the target customer for this being the guy who does simple Smittybilt & Omix-Ada bolt-ons. It's just my opinion, but it seems the guy that would do this mod is a little more hands-on & willing to work through issues to get superior braking for less cost. Just my 2 cents, but I would.
As for the knuckle mod: I don't see the target customer for this being the guy who does simple Smittybilt & Omix-Ada bolt-ons. It's just my opinion, but it seems the guy that would do this mod is a little more hands-on & willing to work through issues to get superior braking for less cost. Just my 2 cents, but I would.