11.65" stock brakes - upgrade to power?

[stuchman1]

Hi everyone,

We're working on our MK4. We have 15" tires and 11.65" stock manual brakes from FF. In reading on the forum, I'm wondering if that setup is quite enough or if we should upgrade so our brakes have a bit more stopping power.

There's a lot of talk in various threads about the Gordon Levy 4 brake system, Whitby power brakes and a few other options. Most of those threads are a couple years old and for example I don't even see the Levy system as available anymore.

I'm therefore thinking of going with the Whitby power brake system and wanted to get a fresh opinion from the experts.

Of note, this is for regular street driving. Nonetheless, as others have pointed out, good brakes are important for that inevitable fool who pulls out right in front of you.

Lastly, a friend who has built one put ABS in his. I'd think about that for ours too. Of course that's related but different to my question above - just mentioning it in case it affects people's opinions.

What would you all do?

Thanks as always!
ST

[danmas]

Gordon is on the forum and I have his kit for front and rear. Suggest a quick chat with him. He is listed under vendors.

[cv2065]

If your brakes are setup properly, and you are not tracking the car, I think the manual brakes are just fine for street use. I'll be running them again on my second build. But power steering is a necessity!

[gbranham]

If your brakes are setup properly, and you are not tracking the car, I think the manual brakes are just fine for street use. I'll be running them again on my second build. But power steering is a necessity!

Agreed. I did manual brakes and manual steering on my MkIII. Brakes were just fine, but I longed for power steering. I'm building a MkIV now, and will do manual brakes again, but I ordered my kit with power steering.

[scrubs]

Do power brakes actually increase "stopping power?" I think only if you cannot increase line pressure to the same level without the power. I am on my first build, but can lock up without busting and aneurysm. If you can do that, power will only decrease the effort you put forth since you can't "lock up more," so to speak.

Increased disc radius, for example, would increase "power" as the torque is increased.

Maybe I am fos.

[Jeff Kleiner]

Do power brakes actually increase "stopping power?" I think only if you cannot increase line pressure to the same level without the power. I am on my first build, but can lock up without busting and aneurysm. If you can do that, power will only decrease the effort you put forth since you can't "lock up more," so to speak.

Increased disc radius, for example, would increase "power" as the torque is increased.

Maybe I am fos.

You are correct. And not FOS

Jeff

[scrubs]

You are correct. And not FOS

Jeff

I could be both

[stuchman1]

Do power brakes actually increase "stopping power?" I think only if you cannot increase line pressure to the same level without the power. I am on my first build, but can lock up without busting and aneurysm. If you can do that, power will only decrease the effort you put forth since you can't "lock up more," so to speak.

Increased disc radius, for example, would increase "power" as the torque is increased.

Maybe I am fos.

Good point - I suppose I'm thinking more along the lines of how others seem to have approached this, and I'm not using accurate terminology. Converting from manual to power brakes doesn't necessarily reduce stopping distances, rather presumably the car might stop faster because with power brakes you can generate the force to maximize braking sooner than without that help. But as I think about this more, I wonder how much of an actual impact that has on stopping distance. Probably not much...

Thanks all for the input!
ST

[Hoooper]

Better tires improves braking distance dramatically. If you can already relatively easily generate enough force to lock up all 4 tires, improving your braking technique to only reach the edge of traction is the first improvement, then tires are the next step. If it is hard to generate enough force to reach the edge then more torque could help improve braking, and that could come from bigger brakes, more aggressive pads, more master cylinder le.

Modern or even just semi-modern ABS is the biggest improvement you can ultimately make since it can put you right at the traction threshold on every tire, something that is not physically possible in the real world without ABS.

I think what you see is that most people converting to power brakes dont like the amount of pedal pressure it takes to stop or the pressure it takes makes them uncomfortable, whatever the reason might be for that issue in that specific case.

[Mbufford]

Do power brakes actually increase "stopping power?" I think only if you cannot increase line pressure to the same level without the power. I am on my first build, but can lock up without busting and aneurysm. If you can do that, power will only decrease the effort you put forth since you can't "lock up more," so to speak.

Increased disc radius, for example, would increase "power" as the torque is increased.

Maybe I am fos.

All accurate, except FOS. However, the older I get, the less interested I am in simple things, like pressing a brake pedal, requiring any more physical effort than bare minimum. That’s the only reason I’m going with a hydroboost—because it reduces the effort required. It I’LL also be running ABS, so higher lockability combined with lock protection should result is easier and shorter rapid stopping.

[scrubs]

All accurate, except FOS. However, the older I get, the less interested I am in simple things, like pressing a brake pedal, requiring any more physical effort than bare minimum. That’s the only reason I’m going with a hydroboost—because it reduces the effort required. It I’LL also be running ABS, so higher lockability combined with lock protection should result is easier and shorter rapid stopping.

I get it...getting older too.

[CraigS]

Rather than going w/ a multi $100 upgrade you may want to consider better brake pads. Hawk HPS, HPS5.0, HP+
Street compounds;
https://www.hawkperformance.com/compounds/street
Race including HP+;
https://www.hawkperformance.com/compounds/motorsports
As you can see the HP+ has significantly more grip. I ran them on the rear w/ HPS or HPS5.0 on the front to help get more rear brake before I went to a bias adjustable MC system. Later I did a 2015 IRS upgrade and used the OE calipers which were significantly larger than the old Fox rear discs so that fixed the rear grip inadequacy and I went to HP+ on the front too. This gave a pedal effort almost identical to my Tacoma pickup. Generally pads are about $100 an axle so a fairly inexpensive experiment. HP+ do dust more than normal. I fixed that problem two ways. A dedicated small shop vac w/ a brush attachment to clean the wheels. Also I used this;
https://www.armorall.com/product/out...ust-repellent/

[stuchman1]

So helpful. Thanks everyone. The support on this forum that newbies such as myself can receive is really one of a kind.

[Benchwarmer]

This thread has some good information that I've been looking for.

[BEAR-AvHistory]

I have the optional Mustang Cobra rear & recently upgraded last year to the Mustang Cobra in front from the FFR GT standard brakes. System is leg powered. Reason for upgrade was to get the larger front disk for looks, 17" wheels.

Based on experience when I had the FFR half & half system (Cobra R & GT F) brakes for road use & fun level AutoX the key is the pads. First runs with the car on FFR pads was a white knuckle experience. Swapped the pads out in early 2015 for the then currant HAWK HPS Front & HP+ in the rear.

Was like I switched to exoctic car brakes stopping in well under 100FT from 60MPH. Currently run the HAWK HPS 5.0 pads on all 4 wheels.

Only change I would make on how I built is to use power steering. Am 82 now & very tight 180* or more AutoX turns are getting to be a challenge in getting the wheel turned quick enough. Upper body strength has drifted away a bit over time.

[John Ibele]

Upper body strength has drifted away a bit over time.

This sounds so much better than upper body strength just plain going down, which is what mine is doing.

[Benchwarmer]

I'm so glad I found this thread. Good info here!

[nuhale]

I used a hydroboost setup on my MKIV. First, +++ on PS. I would do this again. The power brakes, not so much. Not a dig on the hydroboost setup as it works fairly well and is a good setup but wish I had more pedal feel in the drive. I've made quite a few adjustments over the years. First setup was the mustang 11" brake kit and pads that FFR supplied. I think they were Wagner pads. Even with the hydroboost I couldn't get them to lock up and was ok for speed limit driving (not implying anything here . Then upgraded the pads to Hawk HPS. HUGE DIFFERENCE. Upgraded again (cause why not) sometime later to the power stop COBRA SVT 13" fronts with powerstop pads. This performs similar to the 11" with HPS. They lock up easy. Couple reaction brakes where locked up all 4 quite easy without feel. If I did it all over again I would go with the 13" powerstop setup over the stock mustang GT brakes with decent pads, no boost. Just my $.02

[Kbl7td]

Change the masters to 5/8, more pressure, more pedal travel, less pedal force needed. Not sure why that hasn’t been mentioned.

[Alec]

Just another opinion/build plan to add to the chorus. I have Wilwoods, which FFR sold to me with the kit, with the standard master cylinders, no power brakes or ABS. Car stops very very well. Of course this car is very light, so you don't need to go overboard. I worry more about losing control sideways than having to stop fast in a straight line (neither have been an issue yet at 1000 miles). I took some time to get used to the feel of the manual brakes. I could lock up the wheels pretty easily, but it does take more pedal effort than you are used to in your modern car with power brakes. I had another FFR cobra owner drive mine and he said they felt great to him. I am now completely accustomed to the brake feel and wouldn't change a thing. I do have hydraulic power steering, and I am glad I do, but the assist is actually a bit too much, especially at highway speeds, and I have been planning to put a valve in for adjustable power steering pump pressure.