Switched to 35's and feel like a brake upgrade is necessary - Jeep Wrangler Forum
Jeep Wrangler Forum

Go Back   Jeep Wrangler Forum > JK Jeep Wrangler Forum > JK General Discussion Forum

Join Wrangler Forum Today


Reply
 
Thread Tools

Please support our sponsors and let them know you heard about them on WranglerForum.com
Old 10-18-2013, 06:16 PM   #1
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Switched to 35's and feel like a brake upgrade is necessary

Well it's now been 2 days of riding on 35x12.5's with a combined tire/wheel weight of 102 lbs estimated. Coming from 4 piston Brembo's on my STI the stock JK brakes were just "OK" and now that I've increased the wheel/tire size and weight I am feeling like my braking distances are significantly affected.

I am going to go with the Teraflex Big Brake kit I assume as it's the only well known bolt on kit I know of.

Any other suggestions? Are their any stock vehicle Mopar parts that bolt on like Grand Cherokee brakes or something, maybe a 2 piston design with larger rotors in the 12" + range?

I knew it would affect braking but considering my past and my preference for super strong brakes I know already that I am not going to deal with this too long.


Doctorsti is offline   Quote Quick Reply
Old 10-18-2013, 07:05 PM   #2
Supporting Member

WF Supporting Member
 
Join Date: Jan 2013
Location: Southeast PA
Posts: 783
Whatever you wind up doing, I am following this with great interest. I also feel that the stock brakes on the stock Jeep are only marginal, and I was wondering how much the bigger tries would further reduce their performance.

From what I have read, it looks like most people seem to think the Black Magic Brake kit is one of the best options. Granted, it costs over 1000$, but it also comes with pretty much everything you need for a full upgrade.

I am no brake expert, but I have read some people that say better pads are all you need, and others say the pads are not the main problem because the stock master cylinder is undersized. Needless to say, I am interested to see how other people have addressed this and what they wound up going with.

__________________
JKR10A - 2d, 6 speed, black / black
Ordered on 01/24/13
Acquired on 05/03/13
Aeschylus is offline   Quote Quick Reply
Old 10-18-2013, 09:08 PM   #3
Jeeper
 
Kelsey73's Avatar
 
Join Date: Jul 2011
Posts: 1,258
There is a thread over at the AEV forum going on right now for a brake upgrade. I agree on the brakes and will be upgrading to the overseas JK heavy duty part from Mopar.
__________________
2012 Wrangler Unlimited Sahara- Bright White
Kelsey73 is offline   Quote Quick Reply
Old 10-18-2013, 09:19 PM   #4
Jeeper
 
Join Date: Jun 2013
Location: Dfw
Posts: 184
What all does the kit contain? Don't just upgrade the brakes, upgrade the entire system (booster, master cylinder, etc.).
JeepCourtney3700 is offline   Quote Quick Reply
Old 10-18-2013, 09:19 PM   #5
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Quote:
Originally Posted by Kelsey73 View Post
There is a thread over at the AEV forum going on right now for a brake upgrade. I agree on the brakes and will be upgrading to the overseas JK heavy duty part from Mopar.
I saw that too, wasn't the total cost like 450 or something? For 150 more I think I would just opt for the teraflex kit.

There is a thread on another forum where a member is engineering a 4 piston caliper option that I'm keeping my eye on.

With as poor as I feel the brakes control my unarmored JKUR on 35's I figured I couldn't be the only one.
Doctorsti is offline   Quote Quick Reply
Old 10-18-2013, 09:30 PM   #6
Jeeper
 
Kelsey73's Avatar
 
Join Date: Jul 2011
Posts: 1,258
Quote:
Originally Posted by JeepCourtney3700 View Post
What all does the kit contain? Don't just upgrade the brakes, upgrade the entire system (booster, master cylinder, etc.).
The overseas package is calipers, rotors and a new master cylinder.
__________________
2012 Wrangler Unlimited Sahara- Bright White
Kelsey73 is offline   Quote Quick Reply
Old 10-18-2013, 09:31 PM   #7
Jeeper
 
Kelsey73's Avatar
 
Join Date: Jul 2011
Posts: 1,258
Quote:
Originally Posted by Doctorsti View Post
I saw that too, wasn't the total cost like 450 or something? For 150 more I think I would just opt for the teraflex kit. There is a thread on another forum where a member is engineering a 4 piston caliper option that I'm keeping my eye on. With as poor as I feel the brakes control my unarmored JKUR on 35's I figured I couldn't be the only one.
I haven't added it up yet but that sounds close. I'd rather stick all mopar.
__________________
2012 Wrangler Unlimited Sahara- Bright White
Kelsey73 is offline   Quote Quick Reply
Old 10-18-2013, 10:14 PM   #8
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
68044865AA disc brake caliper adapter x2
68049018AA disc brake pin kit x2
68044862AA Caliper right x1
68044863AA Caliper left x1
68044866AC front brake pads x1
68040177AA 13" Front rotor x2
68091278AB Master Cylinder x1
68045999AB Power Brake Booster x1

For this option I priced out the parts from an online supplier and it's about $850 shipped for everything. I have a 2013 so it looks like I can omit the MC and Power brake booster, is that correct? If so it's about $230 less so $620 for the "heavy duty" kit with 13" rotors.

It was posted on another forum that the Power brake booster and master cylinder are the larger ones from the "heavy duty" euro brake kit but I don't know how to confirm that.

Same price as the Teraflex kit with an upside that all parts are Mopar parts with part numbers that can be easily sourced for a very long time but downside that it's still only a single floating caliper design and not a two piston floating caliper like Teraflex.

$620 is a lot of coin to blow on a "minor" upgrade so I will keep up my research to see who is running this combo and how it's holding up to brake fade and such.
Doctorsti is offline   Quote Quick Reply
Old 10-18-2013, 10:32 PM   #9
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Was also looking at making it REALLY simple and getting the teraflex performance rotor kit but then I saw how much they want for replacement rotors... $134 each, yikes. Are these rotors available elsewhere cheaper like are these from a Dodge Ram 1500 or something?

$280 bucks for 30-40 less ft in stopping distance seems like a no-brainer and something I may just have to give a shot considering the recent cash outlay for everything else I've been doing. Thing is my brakes are only 5500 miles old so I would hate to scrap all the parts and spend a bunch of money to buy new ones. This seems like a great choice for now and when the pads wear out look into going with something bigger (which may be an absolute necessity when I finally give into the Siren's song from Ripp!)


Edit: looks like they can be had for under 100 bucks each for the front non-slotted rotors and right around 100 for the slotted version. Powerslots for the Ram are 90$ as it is so I guess it's a small price to pay to have rotors redrilled for 5x5 pattern. That's not horrific but still if they are proprietary then it's kind of a risk. Not that I think Teraflex is going anywhere anytime soon and I suppose if supplies dried up it would just be an excuse to go with another BBK!
Doctorsti is offline   Quote Quick Reply
Old 10-18-2013, 11:35 PM   #10
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Upon further research it appears as though the BRY (my brakes on 2013 JKUR) have the same calipers and pads as the BR6 "heavy duty" option so the only difference is the rotor and the adapter bracket, which makes it nearly the exact upgrade Teraflex is offering.

to buy just the rotors and adapters should cost between $235 and $275 depending on the discount a dealer would offer on the parts they would have to order.
mounts are $37 MSRP each x2
rotors are $119 MSRP each x2

Going with straight Mopar parts might be a safer option, I wonder if a dealer would even notice a difference? I doubt many know much about the BR6 option as it's export only on the diesel Wranglers and if all the parts are Mopar I think I might just plead ignorance ("Yeah, those were the parts on there, I have no idea Mr. Service writer")
Doctorsti is offline   Quote Quick Reply
Old 10-18-2013, 11:59 PM   #11
Jeeper
 
Join Date: Sep 2013
Location: Arizona currently
Posts: 210
Brake upgrades have a lot of pitfalls, more than almost any other kind of upgrade. Changing the friction level of the brakes can play hell with the anti-lock brake system, which is going to negatively impact your stability control, roll mitigation, and brake-based differential (if you have it). It will also mess with the brake balance, because the braking power balance between front and rear brakes is not going to be the same as stock - this can result in squirrely behavior under hard braking, like extreme understeer or extreme oversteer, depending on which axle locks up first and activates the ABS.

I've done a lot of track-day stuff and have messed around with brakes quite a bit for my track-prepped Mustang. My take-away on brakes has been this:

- Upgrading your braking power is pointless unless your brakes are no longer able to activate the ABS. If you can still lock up the brakes, you have enough braking power and stopping distances are not going to change meaningfully with brake upgrades.

- Upgrading the friction level and swept area of your brakes (larger discs and more aggressive pads) will not change your braking distances meaningfully. All it will do is reduce brake fade. This is extremely useful on a track with hard stops from high speeds are done repeatedly. It's almost meaningless off-road.

- Given that off-roading and even pre-running are not anywhere near as brake intensive as track-work, I don't see any point in a brake upgrade if you can still trigger your ABS.

- On the other hand, upgrading your brake LINES can make a huge difference in brake feel and ease of brake modulation. It will completely change the pedal feel of the brakes and eliminate the bulge in the brake lines which is responsible for perceived brake weakness. Since the physics of larger diameter tires essentially reduces brake leverage, adding steel braided brake lines would greatly impact perceived braking performance. It will make the brake-pedal-pressure far more linear, which, in practice, is going to make it feel like you don't have to press as hard on the brakes to lock up the ABS. It will also not mess with your brake balance, since the actual friction level between the pads and rotors isn't changing.





So...yeah. For an off-road application, unless you've decreased the leverage of your brakes to the point of not being able to activate the ABS, switching to steel braided brake lines is going to give you the biggest braking performance upgrade, by making brake response significantly more linear and controllable with the pedal. Steel brake lines really do make a huge difference.....they eliminate the mushy pedal feel almost completely. I'd be very interested in hearing what a Jeeper who's made the switch to steel braided brake lines has to say. I know for my vehicle, it made the biggest difference in braking.
MHShale is offline   Quote Quick Reply
Old 10-19-2013, 07:38 AM   #12
Jeeper
 
Join Date: Sep 2013
Location: Arizona currently
Posts: 210
You also need to get a procal or other tuner and change the vehicle settings to reflect the actual diameter of your tires. The speedometer isn't the only thing affected - your ABS and traction control systems will not be working correctly unless you change the computer settings to reflect the larger diameter tires.

If your ABS is activating really early (or conversely, letting the wheels lock up too much), recalibrating could significantly improve your stopping distances. If recalibrating doesn't help and the ABS is still activating sooner than you're used to, the culprit is your new tires.

Other than that, you're just not going to get much improvement in braking distances without switching to a tire designed to get good braking distances on pavement. Yours aren't. So, brake lines to improve the feel (a lot!), ensure you're properly calibrated...and save a bunch of money on brake upgrades that won't actually do anything.

The only situation I can see larger rotors and fancier calipers helping is if you are using your JKU to tow 3500lbs down an extended grade, and relying on the brakes to hold a steady speed. THAT will heat your brakes up very quickly, so larger rotors will help with fade. I really can't imagine what situation you're be in other than that where you're going to experience any kind significant brake fade in a wrangler (unless you add hundreds of pounds of armor/bumper/winch stuff, and I see in your pic that you haven't...great looking rig btw) The weight increase of your wheel/tire package is pretty negligible on a vehicle that was 4600lbs to start with.

Finally - how many miles have you put on your new tires? It can take up to 500 miles of normal driving to break in new tires, which still have release-lubricant (to keep them from sticking to the tire mold) on them from the factory. Your braking performance will increase SIGNIFICANTLY once your tires are broken in. If you've only been driving around on them for 2 days, it's highly likely that your braking performance is going to improve a lot over the next couple hundred miles (along with cornering ability).
MHShale is offline   Quote Quick Reply
Old 10-19-2013, 11:06 AM   #13
Jeeper
 
Join Date: Jun 2013
Location: Dfw
Posts: 184
MHShale is spot on! Upgrade the brake lines to stainless steel, upgrade the master cylinder and brake booster and you should be good to go without needing to change the rotors, calipers or discs.
JeepCourtney3700 is offline   Quote Quick Reply
Old 10-19-2013, 11:18 AM   #14
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Wouldn't the brakes follow simple physics. Larger diameter rotor = larger radius, in this case "moment arm" for the brake caliper to act on? It requires less force using a longer moment arm to reduce the rotation of the wheel. I don't deny that braided lines will be effective at reducing a mushy pedal or free play from initial bite to locking up the brakes but they don't provide any change in brake torque production.

Straight from Stoptech who I think probably have a wee bit of brake engineering knowledge:

1) Line pressure can only be increased by either increasing the mechanical pedal ratio or by decreasing the master cylinder diameter. In either case the pedal travel will be increased.
2) Clamping force can only be increased either by increasing the line pressure or by increasing the diameter of the caliper piston(s). Increasing the size of the pads will not increase clamping force. Any increase in caliper piston area alone will be accompanied by an increase in pedal travel. The effectiveness of a caliper is also affected by the stiffness of the caliper body and its mountings. It is therefore possible to reduce piston size while increasing caliper stiffness and realize a net increase in clamping force applied. This would typically improve pedal feel.
3) Only increasing the effective radius of the disc, the caliper piston area, the line pressure, or the coefficient of friction can increase brake torque. Increasing the pad area will decrease pad wear and improve the fade characteristics of the pads but it will not increase the brake torque.
Doctorsti is offline   Quote Quick Reply
Old 10-19-2013, 11:19 AM   #15
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
This is what I thought and what Stoptech reports on hoses:

1) Brake hoses: Optimum pedal firmness cannot be achieved with the stock fabric reinforced rubber flexible hoses which swell under pressure - decreasing pedal firmness while increasing both pedal travel and brake system reaction time. The first step in upgrading the braking system of any vehicle is to replace the OEM flexible hoses with stainless steel braid protected flexible hoses of extruded Teflon. Make certain that they are designed for the specific application, are a direct replacement for stock and are certified by the manufacturer to meet USDOT specifications. A claim that aftermarket hose are certified by the DOT is a caution flag. The DOT does not certify anything. Manufacturers certify that their products meet DOT specifications and legitimate suppliers can produce reports from DOT approved testing laboratories. When upgrading your brake hoses, replace both the front and rear hoses. Due to their swelling under pressure the stock hoses take a measurable amount of time to transmit pressure to the calipers. Replacing the front hoses only will result in a built in lag time to the rear brakes and may also adversely effect the microprocessor control algorithms of the ABS system.


Changing brake lines to less compliant tubing only gives the sense the brakes are more powerful as there is less pedal excursion from initial bite to full lock. There is no delay like there is with rubber hoses.

I don't believe brake hoses are the answer for increased rotating mass requiring more force to slow it down.
Doctorsti is offline   Quote Quick Reply
Old 10-19-2013, 11:47 AM   #16
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Quote:
Originally Posted by MHShale View Post
- Upgrading the friction level and swept area of your brakes (larger discs and more aggressive pads) will not change your braking distances meaningfully. All it will do is reduce brake fade. This is extremely useful on a track with hard stops from high speeds are done repeatedly. It's almost meaningless off-road.
So you are stating that an 11 inch rotor with size x brake pad will be just as effective at slowing the rotating mass as a 13 inch rotor with size 2x pad area/contact patch, given the same fluid line pressure. False, it just doesn't obey the laws of physics. Increasing mu (coefficient of friction) increases resistance, not it's ability to resist fade.

Decreasing fade has more to do with the mass, material, caliper, brake pad in terms of them being heat sinks. The faster they can dissipate heat the less fade due to boiling the fluid in the caliper, gassing of the pad, or glazing the pad by overcoming mu.

If I was concerned primarily about fade because I was driving my JK on a track I would upgrade cooling, brake pad material to higher temp (not higher friction), and change out the fluid to one rated for higher temperatures to resist it vaporizing. Gasses are far more compressible then fluids = dynamic fade.
Doctorsti is offline   Quote Quick Reply
Old 10-19-2013, 11:55 AM   #17
Jeeper
 
Join Date: Sep 2013
Location: Arizona currently
Posts: 210
Quote:
Originally Posted by Doctorsti View Post
This is what I thought and what Stoptech reports on hoses:

1) Brake hoses: Optimum pedal firmness cannot be achieved with the stock fabric reinforced rubber flexible hoses which swell under pressure - decreasing pedal firmness while increasing both pedal travel and brake system reaction time. The first step in upgrading the braking system of any vehicle is to replace the OEM flexible hoses with stainless steel braid protected flexible hoses of extruded Teflon. Make certain that they are designed for the specific application, are a direct replacement for stock and are certified by the manufacturer to meet USDOT specifications. A claim that aftermarket hose are certified by the DOT is a caution flag. The DOT does not certify anything. Manufacturers certify that their products meet DOT specifications and legitimate suppliers can produce reports from DOT approved testing laboratories. When upgrading your brake hoses, replace both the front and rear hoses. Due to their swelling under pressure the stock hoses take a measurable amount of time to transmit pressure to the calipers. Replacing the front hoses only will result in a built in lag time to the rear brakes and may also adversely effect the microprocessor control algorithms of the ABS system.


Changing brake lines to less compliant tubing only gives the sense the brakes are more powerful as there is less pedal excursion from initial bite to full lock. There is no delay like there is with rubber hoses.

I don't believe brake hoses are the answer for increased rotating mass requiring more force to slow it down.
You're completely right. Steel braided brake lines will not increase stopping power, only improve pedal feel and make the brakes easier to modulate. It'll help them react a little faster too, enough to take maybe 5-10 feet off a panic stop from 70mph.

And you're right about brake-torque. Larger diameter brake discs and pads with larger surface area will dramatically increase brake-torque.

However...there's no need to increase brake-torque. It won't do anything for stopping power. As long as the brake system is strong enough to lock up the wheels, increasing the power further doesn't do anything at all. A locked-up wheel is a locked-up wheel. Increasing the power further isn't going to lock that wheel up any better.

The brake industry loves selling big brake kits, but the fact is all modern cars have enough brake-torque to lock up the wheels. On a modern vehicle, the only reason to install a set of larger discs and fancy brake calipers is if you are experiencing fade, and that's only going to happen in extreme towing or track environments.
MHShale is offline   Quote Quick Reply
Old 10-19-2013, 12:09 PM   #18
Jeeper
 
Join Date: Sep 2013
Location: Arizona currently
Posts: 210
Quote:
Originally Posted by Doctorsti View Post
So you are stating that an 11 inch rotor with size x brake pad will be just as effective at slowing the rotating mass as a 13 inch rotor with size 2x pad area/contact patch, given the same fluid line pressure. False, it just doesn't obey the laws of physics. Increasing mu (coefficient of friction) increases resistance, not it's ability to resist fade.

Decreasing fade has more to do with the mass, material, caliper, brake pad in terms of them being heat sinks. The faster they can dissipate heat the less fade due to boiling the fluid in the caliper, gassing of the pad, or glazing the pad by overcoming mu.

If I was concerned primarily about fade because I was driving my JK on a track I would upgrade cooling, brake pad material to higher temp (not higher friction), and change out the fluid to one rated for higher temperatures to resist it vaporizing. Gasses are far more compressible then fluids = dynamic fade.
Yes, the 11 inch rotor will be just as effective in stopping the vehicle as the 13 inch one will. The stock system is capable of locking the brakes up immediately upon slamming the pedal. A more powerful system is still only going to lock the brakes up, and then the ABS will activate. There will be no difference in stopping distance beyond normal statistical variation.

Larger brake discs absorb more heat over a larger volume of metal, resulting in lower average surface/internal temperature, and they have a larger surface area, which speeds cooling. Venting and slotting them further increases the surface area. Larger discs and high-heat pads with a brake fluid that has a higher boiling temperature are the best ways to reduce brake fade, along with installing brake ducts. (I have personally done all of these things for my track car)

Stiffening the brake lines reduces the required pedal travel and makes the brakes behave in a more linear manner - this will provide a small increase in panic-stop distance simply due to reaction time.

Since your stock brake system is still capable of activating the ABS, increasing brake-torque via a larger brake kit is just throwing money away. The only time you need an increase in brake-torque is when the traction created by the tires exceeds the brake system's power. In such a case, the brakes would not be able to lock the wheels up. Increasing brake torque only reduces stopping distances up to the limits of the tire's adhesion. Since all modern vehicles' brake-torque exceeds the adhesion limits of their tires, increasing brake torque further will have no effect.

A good article on this:

http://www.autos.com/aftermarket-par...ar-stop-faster

To sum it all up....since all modern cars' stock brake systems generate significantly more force than tires have friction, increasing that force further will not do anything. The system will simply activate the ABS, or lock up the wheel. TIRES are, by far, the best way to shorten stopping distances, because stickier tires take advantage of more of the brake system's brake-torque.

StopTech is in the business of SELLING things. If brake-torque exceeds tire friction limits, your stopping distances are tire-limited, not brake limited. If you can activate your ABS, then your brake-torque already exceeds your tire friction limit. Your Jeep is tire limited.

Just trying to save you money here. Unless you can't get your ABS to activate, then a big brake kit will do nothing besides increase unsprung weight and decrease wallet weight. Make sure your Jeep's ABS system is calibrated to your new tire diameter using a tuner, switch to steel-braided brake lines for increased responsiveness, and remember that until you have a few hundred miles on your tires, they're still partially covered in lubricant from the factory and will not stop as hard as normal.
MHShale is offline   Quote Quick Reply
Old 10-19-2013, 12:46 PM   #19
Jeeper
 
Mopar2Ya's Avatar
 
Join Date: Jan 2012
Location: Earth
Posts: 875
If $ were no object:
http://www.wilwood.com/search/PartNo...desc=Jeep%20JK
I'd like to hear if anyone has any experience w/the Wilwood kit.
__________________
2012 JK U R Crush (Specs in profile)
Pics: http://s1243.photobucket.com/profile/mopar2ya2/index
2006 GC(WK) SRT8 gone
1970 Charger R/T somewhere in pieces
Mopar2Ya is offline   Quote Quick Reply
Old 10-19-2013, 12:57 PM   #20
Jeeper
 
Join Date: Aug 2013
Posts: 54
Quote:
Originally Posted by MHShale View Post
To sum it all up....since all modern cars' stock brake systems generate significantly more force than tires have friction, increasing that force further will not do anything. The system will simply activate the ABS, or lock up the wheel. TIRES are, by far, the best way to shorten stopping distances, because stickier tires take advantage of more of the brake system's brake-torque.....


Just trying to save you money here. Unless you can't get your ABS to activate, then a big brake kit will do nothing besides increase unsprung weight and decrease wallet weight. Make sure your Jeep's ABS system is calibrated to your new tire diameter using a tuner, switch to steel-braided brake lines for increased responsiveness, and remember that until you have a few hundred miles on your tires, they're still partially covered in lubricant from the factory and will not stop as hard as normal.

I can appreciate DoctorSTi's pain as my other vehicles are a 2004 Subaru STi and a 1993 RX-7, both of which weigh much less than the JKU and can stop ALOT faster.

The biggest benefit would be going to a better tire which would resist lock up versus the stock tires currently on the Jeep.

Going to a M/T will only make things worse for braking in my mind.


I would like to improve the 'feel' of braking as it is what I think is the biggest deficiency in the Jeep's braking system. As well the curb weight doesn't help in braking distances. I am already cringing at the thought of ice and snow on the roads
the_saint is offline   Quote Quick Reply
Old 10-19-2013, 01:07 PM   #21
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Quote:
Originally Posted by the_saint View Post
I can appreciate DoctorSTi's pain as my other vehicles are a 2004 Subaru STi and a 1993 RX-7, both of which weigh much less than the JKU and can stop ALOT faster.

The biggest benefit would be going to a better tire which would resist lock up versus the stock tires currently on the Jeep.

Going to a M/T will only make things worse for braking in my mind.


I would like to improve the 'feel' of braking as it is what I think is the biggest deficiency in the Jeep's braking system. As well the curb weight doesn't help in braking distances. I am already cringing at the thought of ice and snow on the roads
I'm running AT tires. Toyo open country AT2

These tires with a 12.5" contact patch should produce "a little more friction" then a 9.5" wide KM2 M/T tire
Doctorsti is offline   Quote Quick Reply
Old 10-19-2013, 02:01 PM   #22
Jeeper
 
Join Date: Jun 2013
Posts: 211
Huge kudos for the great and accurate info in this thread. I think what most people are looking for is brake "feel", which in a non-track setting is typically how much pressure on the pedal is needed to achieve some fixed amount of deceleration. In other words, perceived brake power relates to pedal pressure.

I think the only two things that impact this (that are simple to address) are pad compound and brake lines. I run track pads on one of my street cars (and would run them on another one if it wasn't for the gnarly dust) because I like the high coefficient of friction (I like grabby, immediate braking).

Otherwise, most upgrades address fade resistance, which would seem to be mostly important in towing situations (at least as it related to JK's).
64Chevy is offline   Quote Quick Reply
Old 10-19-2013, 02:27 PM   #23
Jeeper
 
Join Date: Feb 2013
Posts: 1,921
Nice thread... Ever since I put on some heavier components it "feels" like I'm not braking as well.

But theoretically I should just be able to press the brake harder to get the same brake feel as stock, at the cost of wearing out the pads and rotors earlier. Then, as a result, just replace the pads and rotors with OEM parts more frequently as needed.

Am I right?
legitposter is offline   Quote Quick Reply
Old 10-19-2013, 03:26 PM   #24
Supporting Member

WF Supporting Member
 
m998dna's Avatar
 
Join Date: Jan 2012
Posts: 2,322
MHShale ... Spot on brother!

.
__________________
2013 Wrangler JKUR10A 3.6L DOHC - MDH 032515
:: 2002 Chevrolet G3500 LWB 8.1L - motovan
:: 1991 Cherokee Laredo 4.0L HO - resto in-process
:: 2010 Cherokee SRT8 6.1L Hemi - sold
:: 1965 Plymouth Sedan 562ci Hemi - sold
m998dna is online now   Quote Quick Reply
Old 10-19-2013, 04:15 PM   #25
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Quote:
Originally Posted by m998dna View Post
MHShale ... Spot on brother!

.
Spot on for what? Getting rid of the soft pedal feel? If that then yep.

I am looking for stronger brakes to provide the same stopping distances I was achieving prior to 35's without having to push harder on the pedal regardless of how firm or little delay or "modulation" I might be able to get out of lines.

Theoretically my pedal feel would be better with lines and I am not arguing that. I know it will. If this thread was about my mushy pedal I wouldn't have even written it because I would have just added lines. I want to push the same sustained firmness on the brake and the Jeep stop as quick as it used to. I'm not talking emergency, avoid grandma, hardcore slide down some gnarly rock face in Moab, tow the space shuttle, etc... I am simply looking put more brake torque in my system to stop a heavier object without having to push harder. Lazy, spoiled, stupid, I don't really care what that makes me. Larger rotors makes more brake torque, period. I'm looking for more brake torque. There is far more inertia in a heavy E rated 35" tire then in a 32" E rated tire and I want more mechanical advantage in stopping that.

Magnesium bespoke wheels would do the trick also... lessening the rotating mass but I'm not trying to mod my Cuda with 15" wheels. I am simply noting that bigger rotating mass x 4 feels like I have to sustain higher pedal pressures to stop the Jeep. That's simply not lines. If I have room for larger rotors and Chrysler makes parts to add larger rotors. I'm not keeping my 10A stock and looking for tricks to make it "look" stock but perform better, as in a vintage you are trying to maintain aesthetics and history but not die when you push the skinny pedal and go really fast in a straight line after smoking your tires for 30 seconds.

Did everyone read this quote or just see lots of bold words and move on.
3) Only increasing the effective radius of the disc, the caliper piston area, the line pressure, or the coefficient of friction can increase brake torque. Increasing the pad area will decrease pad wear and improve the fade characteristics of the pads but it will not increase the brake torque.
Braided lines don't increase line pressure and they sure as hell don't increase piston area or disc radius or even the coefficient of friction so I'd say if I'm looking for increased brake torque I'm not getting "fleeced" with a BBK.
Doctorsti is offline   Quote Quick Reply
Old 10-19-2013, 04:58 PM   #26
Jeeper
 
Lowerumble's Avatar
 
Join Date: Jun 2012
Posts: 2,000
Quote:
Originally Posted by Doctorsti View Post
Spot on for what? Getting rid of the soft pedal feel? If that then yep.

I am looking for stronger brakes to provide the same stopping distances I was achieving prior to 35's without having to push harder on the pedal regardless of how firm or little delay or "modulation" I might be able to get out of lines.
Yeah, there is alot of great theoretical discussion, but no real answers. The concslusion of this thread certainly can't be that there is no real upgrade and Fiat actually provided the "best" solution already.
Lowerumble is offline   Quote Quick Reply
Old 10-19-2013, 05:31 PM   #27
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Quote:
Originally Posted by Lowerumble View Post
Yeah, there is alot of great theoretical discussion, but no real answers. The concslusion of this thread certainly can't be that there is no real upgrade and Fiat actually provided the "best" solution already.
the proposition here is in no uncertain terms, that adding stainless steel brake lines to the stock JK brakes makes them more then anyone would ever need...

Brake lines make the pedal feel nice but also can get you into trouble as they don't allow any expansion and therefore delay in large braking force. Not a problem for a professional driver but for your everyday Joe who may get a little brake pedal happy when they are coming around a bend in slick weather, too quick modulation of the brakes will put you in a ditch. A little delay or cushion to that amplitude change in brake fluid pressure might just give you that split second to ease up when you unpucker your rear end.

Physics isn't theoretical. Larger moment arm equals same force to slow larger rotating mass. It's math.

I want a stronger brake force to slow me down not a precision pedal feel.
Doctorsti is offline   Quote Quick Reply
Old 10-19-2013, 05:52 PM   #28
Supporting Member

WF Supporting Member
 
m998dna's Avatar
 
Join Date: Jan 2012
Posts: 2,322
Quote:
Originally Posted by Doctorsti View Post
Spot on for what? Getting rid of the soft pedal feel? If that then yep.

I am looking for stronger brakes to provide the same stopping distances I was achieving prior to 35's without having to push harder on the pedal regardless of how firm or little delay or "modulation" I might be able to get out of lines
I'm not arguing you're solution, all I said was a STARTING POINT is swap out the flex lines to braided stainless steel... something that doesn't come with the MOPAR STAGE 3 lift kit, but is a STANDARD PRACTICE with MOST quality aftermarket suspension companies knowing rubber brake lines are a problem and potential safety risk.

I see you like to argue on small insignificant points that are contrary to your beliefs. This is your thread as well as your hard earned money - I'll respect that, however your proposed solutions may not be necessary.

Therefore my messages are mainly for those that wish to take a step-by-step approach as opposed to replacing all the OEM components which does open a can of worms - as you've experienced.

Can we just leave it at that?

.
__________________
2013 Wrangler JKUR10A 3.6L DOHC - MDH 032515
:: 2002 Chevrolet G3500 LWB 8.1L - motovan
:: 1991 Cherokee Laredo 4.0L HO - resto in-process
:: 2010 Cherokee SRT8 6.1L Hemi - sold
:: 1965 Plymouth Sedan 562ci Hemi - sold
m998dna is online now   Quote Quick Reply
Old 10-19-2013, 06:15 PM   #29
Jeeper
 
Join Date: Jan 2013
Location: Newark DE
Posts: 1,255
Quote:
Originally Posted by m998dna View Post
I'm not arguing you're solution, all I said was a STARTING POINT is swap out the flex lines to braided stainless steel... something that doesn't come with the MOPAR STAGE 3 lift kit, but is a STANDARD PRACTICE with MOST quality aftermarket suspension companies knowing rubber brake lines are a problem and potential safety risk.

I see you like to argue on small insignificant points that are contrary to your beliefs. This is your thread as well as your hard earned money - I'll respect that, however your proposed solutions may not be necessary.

Therefore my messages are mainly for those that wish to take a step-by-step approach as opposed to replacing all the OEM components which does open a can of worms - as you've experienced.

Can we just leave it at that?

.
Yeah I guess replacing the rotor and caliper bracket with OEM parts os replacing everything. I also missed where I replaced a bunch of stuff and opened a can of worms. Thanks for your input.
Doctorsti is offline   Quote Quick Reply
Old 10-19-2013, 06:23 PM   #30
Supporting Member

WF Supporting Member
 
m998dna's Avatar
 
Join Date: Jan 2012
Posts: 2,322
You need to change your driving style owning a Jeep... I came out of a Porsche straight to a Jeep, so I know a little about the withdrawals you're going through.

The brakes on my JK are light years ahead of my 1991 Cherokee... my Porsche could stop on a dime.

You have two choices.. adapt or sell it for another STi.

Just a friendly suggestion.

.

__________________
2013 Wrangler JKUR10A 3.6L DOHC - MDH 032515
:: 2002 Chevrolet G3500 LWB 8.1L - motovan
:: 1991 Cherokee Laredo 4.0L HO - resto in-process
:: 2010 Cherokee SRT8 6.1L Hemi - sold
:: 1965 Plymouth Sedan 562ci Hemi - sold
m998dna is online now   Quote Quick Reply
Reply

Tags
brake , brakes , mopar brakes , rotor diameter , teraflex

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Jeep Wrangler Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
User Name:
If you do not want to register, fill this field only and the name will be used as user name for your post.
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.



Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



logo carid shop wrangler parts carid fender flares custom wheels store avs deflectors at carid

» Network Links
»Jeep Parts
» Featured Product

All times are GMT -5. The time now is 12:24 AM.



Jeep®, Wrangler, Liberty, Wagoneer, Cherokee, and Grand Cherokee are copyrighted and trademarked to Chrysler Motors LLC.
Wranglerforum.com is not in any way associated with the Chrysler Motors LLC