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Yeah, I was hoping sooner too... Couldn't wait so I went back to my original plan of the TF BRK for the rear. It's coming in today. Then to decide on doing the front in stages or all at once.

Did you get the Crown BBK and add the Mopar MC and booster as well? If so, it would be great if you would be willing to doing your install in the following stages and letting everyone know your observations after each stage.

1. Crown Front BBK
2. Add Mopar MC+Booster
3. Add Teraflex rears

I installed the Mopar BBK in 2015 and replaced my rear rotors with stock size and added EB Green Stuff pads in the rear all at the same time. It's been great where I didn't feel the need to increase the rotor size for the rears. My viewpoint is that the Mopar MC+Booster increases braking performance in the rear and am concerned adding larger rotors in the rear may create squatting in the rear when braking hard, which is not really what you want. So I would like to hear your observations if you are able to do the install in that order above and provide your observations after you've had time to try it out after each install stage.
 

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Yeah, I was hoping sooner too... Couldn't wait so I went back to my original plan of the TF BRK for the rear. It's coming in today. Then to decide on doing the front in stages or all at once.
Would be nice for at least an update.
 

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My viewpoint is that the Mopar MC+Booster increases braking performance in the rear and am concerned adding larger rotors in the rear may create squatting in the rear when braking hard, which is not really what you want.


Physics says you won't get the rear squatting. You may lock up the rears, but what causes the front to squat is the inertia of the vehicle decelerating. If you're moving forward and hit the brakes, the front wheels slow or stop while the rest of the vehicle wants to remain in motion. That's what causes nose dive.


The only way the rear is going to squat from braking is if you're going in reverse and slam on the brakes.


Also, I did my Crown BBK one weekend and the Mopar Master Cylinder and Booster the next weekend on my 2011 JK.


While the BBK made a noticeable difference in braking, the pedal feel was greatly diminished...had to push the pedal quite a ways before you got into the meat of the brakes.


The master/booster solved that. My pedal now reacts almost immediately, and while I haven't done an "Oh Shit!!!" test, I have no doubt that I could get the brakes fully engaged and still have 1/2 of the pedal travel to spare.


My rears are still stock. I'm hoping that the Crown rear kit will be available before my stock rear pads need replaced.
 

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@Pressurized will you be installing the rears first or wait for the front to do it all at once?
Out of a bit of necessity, I will put the rears on first. I knocked the passenger rear brake line off wheeling last Saturday and I had to "rig" it to get home on mushy as hell brakes. So while I'm in there fixing it, I am going to throw on the BRK kit. My pads are at 50% and clean so I may just keep my existing pads until I do the front. That way I can see if there is a noticeable difference. I don't expect to feel it in normal driving, but I hope I can while towing.

Did you get the Crown BBK and add the Mopar MC and booster as well? If so, it would be great if you would be willing to doing your install in the following stages and letting everyone know your observations after each stage.

1. Crown Front BBK
2. Add Mopar MC+Booster
3. Add Teraflex rears

I installed the Mopar BBK in 2015 and replaced my rear rotors with stock size and added EB Green Stuff pads in the rear all at the same time. It's been great where I didn't feel the need to increase the rotor size for the rears. My viewpoint is that the Mopar MC+Booster increases braking performance in the rear and am concerned adding larger rotors in the rear may create squatting in the rear when braking hard, which is not really what you want. So I would like to hear your observations if you are able to do the install in that order above and provide your observations after you've had time to try it out after each install stage.
My order is likely going to be a little different...

1. TF BRK
2. Crown Kit
3. Mopar MC and booster

So it might not get the exact analysis we're looking for, but I'll report it out for sure. The rear BRK should go on this weekend. Then I want to have the front done before I hit the Mojave Rd trail in January pulling my trailer.

I plan to put on a new rear pad when I do the front kit install. I will likely just match as closely as possible the Crown kit pads which are just a semi-metallic OEM style pad.

Would be nice for at least an update.
I'll definitely update, step by step.
 

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I ended up putting the dynatrac kit on since I got it at the same price as the crown kit. The upgraded rear did make a big difference in my opinion.

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For me, I have a 2013 and i am happy with the brake feel after just the front bbk.

Another quality concern is the bleeder valve seems loose around the threads.
I noticed that if i have the drain bottle below the valve (causing a siphoning effect) air would be sucked in between the threads and back out the tubing. Lots of air was coming out the tube.

Had to keep the valve just barely open and position the drain bottle above the valve so no siphoning. Learned something.

Sent from my Pixel 2 using Tapatalk
 

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For me, I have a 2013 and i am happy with the brake feel after just the front bbk.

Another quality concern is the bleeder valve seems loose around the threads.
I noticed that if i have the drain bottle below the valve (causing a siphoning effect) air would be sucked in between the threads and back out the tubing. Lots of air was coming out the tube.

Had to keep the valve just barely open and position the drain bottle above the valve so no siphoning. Learned something.

Sent from my Pixel 2 using Tapatalk
I didn't notice the bleeder valve being loose on mine. As for the bottle, the little kit that I have says clearly in the instructions to keep the bottle above the valve. It even has a little magnetized clip so you can stick it to the frame while you're bleeding. It makes sense to keep it elevated so that the air will stay in the bottle and not travel back up the hose into the caliper.
 

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I didn't have an issue with the bleeder valves nor did the Crown brake pad clips seem flimsy.

Again, I'm extremely happy with the Crown Front BBK and with the Mopar Performance Master Cylinder and Brake Booster.
 
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Mine is a 2012. It is my understanding that when the engine change was made for 2012, the brake MC changed then as well (2007-2011 being different than 2012+). The bore on the MC from crown was definitely larger than the stock unit it replaced.

My bottom line, if you have a 2012+ and are unhappy with the pedal feel with the stock MC and Booster, dont bother with only the MC. Go all the way and get both the MC and Booster. If you are happy with the pedal feel, leave it alone.

I am still not fully thrilled

Sorry, but I am still not clear on what to buy.


I checked out the Mopar Performance Master Cylinder and Brake Booster (1 ⅛" bore), P5160050, mentioned here, and it claims it is only for 2016 to 2018 JK's.


So, does the "middle child", the 2012 to 2015 JK's, need a better MC+B, or nothing is better than what came stock?


BTW, the Mopar/Crown Master Cylinder 68091278AB is a 1 1/16" bore.
 

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I plan to put on a new rear pad when I do the front kit install. I will likely just match as closely as possible the Crown kit pads which are just a semi-metallic OEM style pad.

When you reach that point of replacing the rear pads, I'ld suggest trying out the PowerStop Z36 pads. I put them on the fronts this past year and they are great pads, especially for their price. I like them better than the much more expensive EB Greenstuff pads I had on previously. They do everything you could hope to expect from a brake pad. Don't make noise, don't leave dust on your wheels, nice increase in stopping power, stainless steel (ie no rust) back plate. They're made of a Hybrid Ceramic material, which seems to eliminate the negative aspects often associated with standard ceramic pads (ie dust, wear faster than semi-metallic).
 

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Physics says you won't get the rear squatting. You may lock up the rears, but what causes the front to squat is the inertia of the vehicle decelerating. If you're moving forward and hit the brakes, the front wheels slow or stop while the rest of the vehicle wants to remain in motion. That's what causes nose dive.

Why are describing what causes the front to squat when I mentioned rear squat? Care to elaborate on these "physics" you're referring to?

An OEM braking system is typically designed with a 60/40 front/rear braking force applied when fully locked up. Under normal braking conditions, that front/rear split is in the 75/25 ranges. If you increase the rear rotor size, that design intent 60/40 split can shift to 40/60 thus more force is being applied on the rears than the fronts and cause the rear to squat.
 

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Sorry, but I am still not clear on what to buy.


I checked out the Mopar Performance Master Cylinder and Brake Booster (1 ⅛" bore), P5160050, mentioned here, and it claims it is only for 2016 to 2018 JK's.


So, does the "middle child", the 2012 to 2015 JK's, need a better MC+B, or nothing is better than what came stock?


BTW, the Mopar/Crown Master Cylinder 68091278AB is a 1 1/16" bore.
I have a 12. The Genuine Mopar Performance Master Cylinder/Booster is definitely different from what came stock. There is no question that the booster is physically larger and so is the master cylinder. The P5160050 kit was the one I bought. The vendor says fits 2007-2018. https://smile.amazon.com/gp/product/B016P7Q74Y/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
 

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Why are describing what causes the front to squat when I mentioned rear squat? Care to elaborate on these "physics" you're referring to?

An OEM braking system is typically designed with a 60/40 front/rear braking force applied when fully locked up. Under normal braking conditions, that front/rear split is in the 75/25 ranges. If you increase the rear rotor size, that design intent 60/40 split can shift to 40/60 thus more force is being applied on the rears than the fronts and cause the rear to squat.
No, the rear will never squat under braking unless you're braking in reverse.

More braking power in the rear may cause the rear brakes to lock up, but it will never cause the rear to squat.

Squat is caused by the fact that an object in motion tends to stay in motion until acted upon by an outside force. When you apply your brakes, the wheel slows or stops. The weight of the vehicle wants to continue moving forward. Since the vehicle is attached by suspension to the wheels, that forward momentum transfers energy in an arc downward through the front springs causing the front to sag.

Even if you only had rear brakes, the front of the vehicle would still squat slightly when applying brakes, though the wheels would lock up before you'd get anywhere near the nose dive you do with front brakes.

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Do this. Get in your Wrangler with your 60/40 front to rear split. Back up at about 20 mph and stand on the brakes. I guarantee you the rear of the Jeep will sag even though the more powerful brakes are up front.

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/\This. The amount of front squat, all else equal, is determined by suspension geometry. Specifically the amount of anti-squat/anti-dive built into the suspension.

Mark

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