Need more stopping power - Page 5 - - The top destination for Jeep JK Wrangler news, rumors, and discussion

Modified JK Tech Tech related bulletin board forum regarding subjects such as suspension, tires & wheels, steering, bumpers, skid plates, drive train, cages, on-board air and other useful modifications that will help improve the performance and protection of your Jeep JK Wrangler (Rubicon, Sahara, Unlimited and X) on the trail.


Need more stopping power


Old 06-18-2017, 04:51 PM
JK Enthusiast
casamtb's Avatar
Join Date: Oct 2013
Location: CLE
Posts: 191
Thanks: 0
Thanked 1 Time in 1 Post

Originally Posted by Dynatrac View Post
Since our pads fit the stock calipers, you can use any OE-type replacement pad if necessary.
thanks for clarifying. Was looking at these and TF obviously. The pricing makes more sense since the progrip a also come with new pads
casamtb is offline  
Reply With Quote
Old 06-18-2017, 04:58 PM
JK Junkie
Rednroll's Avatar
Join Date: Apr 2010
Location: SE Michigan
Posts: 3,062
Thanks: 0
Thanked 29 Times in 27 Posts

Originally Posted by Dynatrac View Post
Our ProGrip kit also includes a set of specially formulated brake pads developed by Dynatrac to work with our ProGrip system and further enhance the increase in stopping power. BUT, you can always use stock-type pads (meaning any pad for a JK you can get from a parts store) if you're ever caught in a situation where getting a replacement set of Dynatrac pads isn't feasible for whatever reason.
This is true in that pads can use different materials to increase stopping power. To eliminate the marketing confusion out of it of special formulations, since all manufacturers of brake pads have special formulations, they are typically given a coefficient of friction rating after going through SAE testing.

There are 2 ways to increase the stopping power with brake pads.
1. Increase the surface area. (not done with the Progrip BBK pads as noted since they use the stock calipers)
2. Make them of materials with a higher coefficient of friction. (Most likely what is increasing braking ability)

Can you share what the DOT coefficient of friction letters are on the Progrip pads?

Also, I need to note that while increased coefficient of frictions are great for increased stopping power, it doesn't come at zero costs. Typically, the higher the coefficient of friction of pads, they then wear faster, they also put much more wear on the rotors, additionally causing the rotors to wear faster, and tend to have more brake dust and are noisy.
Rednroll is offline  
Reply With Quote
Old 06-19-2017, 05:42 AM
JK Junkie
Rednroll's Avatar
Join Date: Apr 2010
Location: SE Michigan
Posts: 3,062
Thanks: 0
Thanked 29 Times in 27 Posts

Originally Posted by nthinuf View Post
There are two different types of upgrades being talked about

The Rotor kits (dynatrac and teraflex) will re-use the stock calipers and stock pads, they just include larger rotors and brackets to move the stock calipers further out.

The front-only Big Brake kits (mopar and teraflex) will include larger rotors, new beefier calipers, brackets to move the calipers out, and then possibly some other items like brake lines, boosters, whatever, depending on kit. Apparently these use larger pads.
For anyone who is interested in learning more about how your brake system works, this video breaks down the components of a brake system pretty well and explains what they do and how they work. Starting at 1:58, it demonstrates the Hydraulic portion of the interaction between the Master cylinder and the Brake caliper pistons. It makes it easier to understand what you gain when you go to a larger caliper.

In most all brake systems, the caliper piston is a larger diameter than the diameter of the Master Cylinder. Thus, there is a mechanical advantage taking place where there is an increase in pressure force applied to the caliper pistons. See the bottom caliper Piston which is larger than the diameter of the MC, and it shows 900N of force is delivered when the same 600N of force is applied at the MC. Thus, when you go to a larger caliper you increase the pressure placed on the caliper piston, to something that is higher than the stock caliper. However, what you should also notice is that it takes more travel of your foot to push that larger caliper piston out, and also takes more fluid to be present in the MC, to be able to fill the larger caliper piston so that it applies that force on to the brake pad and rotor. So to compensate for that, the MC size is also increased to better match the increase in caliper size. Thus, the reason the Mopar kit includes a larger replacement MC. The larger MC increases the amount of fluid that is present and increases the pressure that is generated in the left cylinder in the diagram. So in that diagram example that force goes from 600N, to something larger than 600N. The brake booster is between your floor pedal and the plunger on the MC, that gets pushed on the MC to exert that initial force. Since the amount of force in the MC increased, and if you used the stock booster, it will require you to push harder with your leg to push that MC plunger forward. To take care of that, the Mopar kit added a larger brake booster which adds additional mechanical advantage leverage, so the larger MC no longer requires you to push harder with your leg. The overall net result, is more pressure is applied to Piston calipers, but no negative impact of having to push harder and further with your leg.

Like nthinuf mentions, there are multiple methods being discussed of increasing braking power. I'ld further break them down as such.
1. Increasing Rotor size.
2. Increasing the coefficient of friction of the brake pad material
3. Increasing the surface area of the brake pad.
4. Increasing the Hydraulic Force applied to the brake pads and rotors.

The Dynatrac Progrip BBK system, adds more stopping power by using items 1&2 on the front and rears.

The Mopar BBK uses items 1, 3, & 4 on the front and item #4 on the rears.

So to say the Mopar kit ignores the rears, is not correct. What I additionally did when installing the Mopar kit, was that I replaced the rear pads with a set that increases the coefficient of friction which then adds item #2 of additional stopping power to the Mopar kit. If I need more braking power, I could also replace the pads in the front with a pad which has a higher coefficient of friction which would give me items 1,2,3,&4 for the front which is a much more simpler of an upgrade path than trying to later add a replacement MC, Calipers, booster and larger pads which would be the next steps that would be needed if you needed further braking performance increases on the Progrip BBK. The benefit of the Progrip system, is in the initial install of re-using the stock hydraulic components, and adding items 1&2 to the rears. Dynatrac, will gladly tell you about those advantages and many may be happy with that solution. What they don't tell you about are the potential negative aspects. Who does? Listen to any vendor and their solution is always just peaches and cream. The negative aspects of their BBK solution will be that it tends to have more associated wear on the rotors and pads, as well as more potential associated noise and dust, and that if you find yourself in a situation for a need of more braking power capability, then you're looking at other options to address items 3 & 4. Like lifts, no BBK is perfect out of the box. I just preferred to go with one, that put me more on the path towards being the more complete solution and btw, cost less for my initial investment, cost less for the replacement parts that typically wear out on a brake system, and cost less for further upgrade options. YMMV.

Last edited by Rednroll; 06-19-2017 at 05:51 AM.
Rednroll is offline  
Reply With Quote
Related Topics
Thread Starter
Last Post
JK Show & Tell
04-06-2011 04:30 AM
Stock JK Tech
01-26-2011 11:14 AM
JK Show & Tell
01-15-2011 06:37 PM
JK Electrical, Lighting & Sound Systems
06-10-2008 07:36 PM

Posting Rules
You may not post new threads
You may not 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

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

  • Ask a Question
    Get answers from community experts
Question Title:
Your question will be posted in: