My own JK 'Big Brake' research:

[Majik]

I'm still reading this great thread for the first time, but wanted to say that Aluminum is going to be 'stiffer' than a steel plate and should minimize deflection under heavy load. I certainly don't know the specs or metallurgy of the steel used, so can't say this is for sure, but...

I worry about a few things with aluminum, though: corrosion due to dissimilar metals being placed in direct contact (although paint can slow this), differing expansion rates when heated, and fatigue. Aluminum fatigues with every stress it endures. Steel has fatigue limits that, if never exceeded, mean that it should never fail due to simple fatigue cycling. If I'm remembering correctly from my materials science classes...

I'd be hard pressed to imagine a 1/2" or thicker steel plate that is only a few inches by a few inches in size flexing enough to cause an issue. Point taken, and probably significant if I was using 1/4" or thinner, but in this case....:idontknow:

 

[jeeeep]

many years ago I worked in a summer in an aluminum manufacturing, I recall they would anodize the aluminum, use a thin gasket at the point of contact and stainless steel fasteners. It wasn't the aluminum that would corrode so much but the steel it was in contact with would rust faster. Why I recall this is beyond me but it's stored in the memory chamber...
Aren't most calipers now made of cast aluminum?? I haven't taken a magnet to mine but I thought the fronts were made of different material than the rears :thinking:

 

[Majik]

many years ago I worked in a summer in an aluminum manufacturing, I recall they would anodize the aluminum, use a thin gasket at the point of contact and stainless steel fasteners. It wasn't the aluminum that would corrode so much but the steel it was in contact with would rust faster. Why I recall this is beyond me but it's stored in the memory chamber...
Aren't most calipers now made of cast aluminum?? I haven't taken a magnet to mine but I thought the fronts were made of different material than the rears :thinking:

I haven't ruled out aluminum. I'll have to check the caliper material just for curiosity's sake. The test ones are heavy as sh**. Probably twice the weight of the factory ones.

And I know there are ways around the corrosion issue. It was one of the lower concerns on my list. My biggest concern was the heat cycling/fatigue issue. I'm sure I'm just beating the issue to death Part of me just feels safer with a 1/2" steel plate holding my brakes on than a 1/2" aluminum plate. I know. Not a very scientific statement, but I think the reasons we've mentioned up to this point are valid

 

[Majik]

On a separate note, I just wanted to invite the expertise of Eddie and any of the other Wayalife gods out there to post any suggestions, too! :bowdown: :bowdown: I noticed alot of new guys to the forum (like me) posting on this thread, but only a handful of the experienced posters. Please...I value the thoughts of everyone! Especially those that have inspired people like me to explore this awesome .... well, Wayalife! I really want to make this an upgrade we can all afford and all do in our garage in a few hours...All ideas and concerns are investigated!!

 

[jeeeep]

I haven't ruled out aluminum. I'll have to check the caliper material just for curiosity's sake. The test ones are heavy as sh**. Probably twice the weight of the factory ones.

And I know there are ways around the corrosion issue. It was one of the lower concerns on my list. My biggest concern was the heat cycling/fatigue issue. I'm sure I'm just beating the issue to death Part of me just feels safer with a 1/2" steel plate holding my brakes on than a 1/2" aluminum plate. I know. Not a very scientific statement, but I think the reasons we've mentioned up to this point are valid

yea, I hear you, don't want failure here...

 

[Majik]

I know next to nothing about brakes, but what if you just reuse the factory front rotors and calipers in the back? Would that get you close to the right ratio with the new front setup?

Dave

So sorry I missed this question when you posted it! I wasn't trying to be rude. I actually have been reading through the entire thread tonight just to check for errors or suggestions I missed...

This is actually an interesting proposal! It would add a vented rotor in the rear to replace that weeny solid rotor. The down side is ironically that the rear stock rotor is actually slightly larger in diameter than the front. So putting the front rotors on the rear will lose a small amount of brake torque just from rotor size alone, but will likely pick up a significant amount of 'squeeze' from the much larger caliper pistons in the front calipers. Also, heat dissipation will be much better from the thicker, vented rotor. I will plug this into my spreadsheet so I can compare the brake bias front to rear using this combination. Good thought! It obviously would save money by just getting to reuse the front parts on the rear... hmmm...:thinking:

 

[dchew]

BTW, do you have a pic of your rig with the 1.5" spacers and the Hutchinson's? I was curious what the stance looked like! Thanks in advance!

You probably want direct head on shots. I don't have any of those but here are a few I do have. I will take a few more when I get home later this evening. Those are Bushwacker fender flares and an Expedition One front bumper.

So sorry I missed this question when you posted it! I wasn't trying to be rude. I actually have been reading through the entire thread tonight just to check for errors or suggestions I missed...
...Good thought! It obviously would save money by just getting to reuse the front parts on the rear... hmmm...:thinking:

What? You missed a post in this thread?? Ha!
Seriously no sweat. Might enable people to do it in stages too if the rotor & caliper are close-ish; redo the front and move the front to the rear, then later upgrade the rear when they need pads and/or rotors.

Ciao,
Dave

 

[dchew]

Oh, and thanks for your link above to Motorsport-tech. I would prefer to run a little more backspacing than I currently have, which is 4.63+1.5=3-1/8". Everyone says 3-1/2" with coil-overs; I'm going to evaluate mine to see exactly how much I can get away with. I just have to bite down and trim off the studs.

Dave

 

[dchew]

Here are a few more shots (total posers). Hopefully this will give you an idea of the stance, at least with Nitto TG's, Hutchinsons and 1-1/2" Spydertrax.. The tire sidewall sticks out 4" beyond the front fenders and 3" beyond the back.

 

[DunnyBunny]

Nice jeep man. That's the color I'm thinking I want but in matte. Mines matte black right now. But no one has your color in matte and I think it will look sick. Maybe a little darker but basically everything you have that is black I also want black. Fenders black as well.

So I haven't read entire post but this is supposed to work with current stock setup as far as hubs and all that right? I think you said you had new hubs or a spyntec conversion. That's a significant amount of money on upgrading just to allow this break upgrade. Sorry if I missed this info somewhere its just getting to be a long thread. Lol.

 

[Majik]

So I haven't read entire post but this is supposed to work with current stock setup as far as hubs and all that right? I think you said you had new hubs or a spyntec conversion. That's a significant amount of money on upgrading just to allow this break upgrade. Sorry if I missed this info somewhere its just getting to be a long thread. Lol.

No. I'm doing the Spyntec conversion. I am building this kit so it works with STOCK hub setup. If you have a Spyntec or similar conversion, the only thing you should have to do in addition is double-drill the rotors to a 5 on 5.5" bolt pattern and bore the center hole from 71.5mm (stock JK) to 107mm (stock CJ). This is about $30 per rotor at a machine shop. But to answer your question, no...this build/research is designed for everyone to use on a stock setup JK.

 

[DunnyBunny]

Ahh. Ok. Thanks. I'm sure I read that before as I started following this thread a while back. Just so much info I've forgotten half of what I have read lol.

 

[Majik]

Here are a few more shots (total posers). Hopefully this will give you an idea of the stance, at least with Nitto TG's, Hutchinsons and 1-1/2" Spydertrax.. The tire sidewall sticks out 4" beyond the front fenders and 3" beyond the back.

<img src="http://wayalife.com/attachment.php?attachmentid=32089"/>

<img src="http://wayalife.com/attachment.php?attachmentid=32090"/>

<img src="http://wayalife.com/attachment.php?attachmentid=32091"/>

<img src="http://wayalife.com/attachment.php?attachmentid=32092"/>

<img src="http://wayalife.com/attachment.php?attachmentid=32093"/>

Awesome jeep!!! And those pics were exactly what I needed. Except I ordered my wheels in black Thanks again!!

 

[dchew]

...Except I ordered my wheels in black

As you should. Goes much better with Gecko!

 

[Majik]

Gonna try to take some really detailed measurements for the caliper adapter tonight. First, however, I'm gonna install my evap canister relocation bracket tonight. Decided on the one from Nemesis industries. I know there are a ton out there. I just needed some small project to do with my kids that wasn't break related for an hour The rest of my pile of parts in the garage kinda has to all go on at the same time. (C-gussets, axle sleeves, Reid knuckles, RCV shafts, ball joints, hubs, R&P...phew!) :whew: Just glad I found one thing I could do and accomplish in an hour or so!!

I'll try to post a few details or a rough drawing of the adapter bracket late tonight or tomorrow once I get some detailed measurements...

 

[Prime8]

Gonna try to take some really detailed measurements for the caliper adapter tonight. First, however, I'm gonna install my evap canister relocation bracket tonight. Decided on the one from Nemesis industries. I know there are a ton out there. I just needed some small project to do with my kids that wasn't break related for an hour The rest of my pile of parts in the garage kinda has to all go on at the same time. (C-gussets, axle sleeves, Reid knuckles, RCV shafts, ball joints, hubs, R&P...phew!) :whew: Just glad I found one thing I could do and accomplish in an hour or so!!

I'll try to post a few details or a rough drawing of the adapter bracket late tonight or tomorrow once I get some detailed measurements...

I just drilled a new hole in my current factory evap skid to relocate it a couple inches over. Free and took about 10 mins...

 

[MTG]

Gonna try to take some really detailed measurements for the caliper adapter tonight. First, however, I'm gonna install my evap canister relocation bracket tonight. Decided on the one from Nemesis industries.

If you don't mind, let me know how you like that one once it's installed. Need to do this myself. :doh:

 

[Majik]

If you don't mind, let me know how you like that one once it's installed. Need to do this myself. :doh:

Will do! Kit so far is very well designed. Clean, simple. After really trying to beef up the underside of my Jeep with full skid system, rails, etc, that evap just looked like it was begging to be ripped off. Just printed the install instructions (I like paper while under the vehicle... Not my tablet) and they seen superbly detailed with excellent pics. I'll let you know soon.

 

[rws]

Are those rotors and this whole set up available in an 8x6.5 set up? I'm running the TF upgrade right now on 40's but building big axles rights now for it.. Awesome thread btw, love the research..

 

[Majik]

Are those rotors and this whole set up available in an 8x6.5 set up? I'm running the TF upgrade right now on 40's but building big axles rights now for it.. Awesome thread btw, love the research..

Unfortunately not. At least not in an 'off the shelf' style build. The offset on the rotor hat on most OEM 8x6.5 rotors is too great (the rotor would run into your ball joints), and you can't double-drill a 5-lug rotor for 8 lug because you would run the lug holes into each other at a few spots. If I locate a stock 8 lug rotor that will not have a huge offset, I'll let ya know! :thumb: