In reply to Tom1200 :
Sorry if I am not as clear as I am intend. I am taking advice from better drivers than myself on brakes and braking. I'm braking as hard as I can without upseting the car coming off the brakes. One mustang guy who gets ftd has had me working on hard braking, it was also advice I was given when taking evo school. As you can imagine it's easy to upset this car if you don't get on and off the brakes in the right manner. When I have had instructors or better drivers with me over the last year, brake improvement has come up, one fellow told me I was at the limit of the equipment. I was going to upgrade the whole system this year, alas all the other cars are screaming for money like baby robins for worms. This is where the cheaper option of just pads came up. Again, after one of the better drivers with a gt 350 R rode with me, he suggested brake upgrades. I probably should have mentioned that the mustang is supercharged.
So I used the word "stomping", to indicate I am using the brakes, as I have been told. I have not engaged abs and feel like I would upset the car if I did so. I am more than willing to try it though.
I think they are mainly asking about ABS to see if you are actually fully using the brakes and getting to the limits of the tires. I'm guessing on an 06 the ABS isn't going to be good enough to actually see a performance improvement over threshold braking unlike something built in the last 5 years or so where it can.
I think a pad and rotor change will get you where you want to be for autocross. Something more aggressive should result in less pedal effort which should hopefully be easier to modulate and be more consistent over a run (or multiple runs). I've been happy with Hawk HP+ in the past, they work well from cold but get better with a bit of heat in them, they will dust a lot but that is true for any pad in this category. For a cheaper option that will should work just as well you can get the Powerstop Track Day pads for your car through Rockauto (don't forget the 5% off code through this forum). I'm with Bobzilla on the expensive pads with cheaper rotors idea, I either buy local or get something like a Centric C-tek rotor if I'm buying through Rockauto.
Add in a fresh, decent fluid with the above and I think you will be very happy with the improvement over what you have right now. I think a lot of people go to a "big brake kit" (often just on the front throwing off brake bias) right away when a set of pads would give them everything they need. In your case with the extra power over stock if you move on to track stuff larger rotors and calipers will likely be justified (but you'll still need the aggressive pads with those too).
I’m currently running HP+ on my 08, with stock rotors. 20-30 minute sessions they adequate at best, my next upgrade is cooling. For autocross pads may be all you need.
Now to answer your question. Bang for the buck upgrade especially if you are buying pads and rotors anyway is to use rotors from an 11-13 V6 or GT, they are bigger use the same caliper you just need to change the caliper bracket. Last time I looked brackets were available at RA.
I’m saving for the 07-12 14” Gt500 Brembo kit. My buddy works at Ford and can get a deal on the parts.
In reply to thedoc :
Thanks for the clarification and yes the car being supercharged now explains things. If you've been to Evo school they'll have sorted any technique issues.
So at t this point I'd go with a more aggressive pad that still worked on the street. While it is true you can only use as much brake as you have tire I find that pads make a lot of difference on how effective threshold braking is. If the braking isn't progressive it makes it difficult to get the most out of them, so try and find a set that offers really good feedback along with the extra bite. Both of my current cars are dedicated race cars so I can't really recommend any dual purpose pads.
Back in the 90s I daily drove Showroom Stock Miata, it used Hawk Blues and they worked great for the street and track but were hard on rotors. I changed rotors every other set of pads.
In reply to Tom1200 :
I ordered some hawk pads before I looked at my rotors, then I ordered some centric rotors. I will report back on how the car feels after the install. As always, thanks so much for the advice and patience on my lack of clarification!
In reply to thedoc :
Make sure to flush your fluid. It can make just as big a difference.
Yes please report back it will be interesting to read.
You can get re-manufactd 4 piston Brembos (07-10 GT500, 11-12 boss) from Advance/Auto Zone/ Pepboys for $100 per side, 14" rotors for $50-$75 each, new brake hoses and pads (street). Total should be around $400 or less.
In reply to fivelinkcobra :
I looked at autozone and could not find this. I’ll look again, Thanks. I do have new parts on the way, but I’ll check this out for sure.
I bought my Evo 9 Brembos from RockAuto a few years back. They come unpainted but it's still the same thing.
In reply to fivelinkcobra :
I have looked at all of those outlets and have not seen this deal. I'll call the store
Ok, Sit rep: Complete brake flush, and I mean two cans of fluid. I even found a neat way to drain the reservoir that I'll post on tips and tricks.
I was told to buy the hawk 5.0 pads by tire rack, they said they would be better for auto cross. I then went and looked at my rotors and thought they could use a turning or replacement . I bought Centric rotors.
One auto cross on the car. It stops better, but no wow factor at all. I don't know what I was expecting, but the reviews said 40 percent improvement and I don't feel that.
My normal crowd was not at the event, so I could not see if my times were better. I will be at events this weekend with them, so I will be more able to see. I did a few runs actively working on harder braking. I upset the car more, so that shows that there is some improvement. Sadly, with covid, I can't get someone to ride with me and give me feedback on my braking.
I will have more info after this weekends events.
Thanks so much for your input.
I found the HPS pads to be very nice street pads but the HP+ have a much better bite without needing to warm up nearly as much as the DTC track pads. The HPS are what I intend to keep on my track retired GTI, the Frankenstang will, probably, eventually wear a combo of DTCs on track and HPS to the track. The HP+ are a good pad, though, and work well on the street, a nice intermediate pad for getting serious about braking. The reworked compound, same as HPS vs HPS 5.0, is a little quieter and less dusty. They are rougher on rotors, though, so take that into account. What made up my mind was the friction chart that is floating around, from Hawk, and the HP+ are much more linear than the HPS.
I don't autox so, of course, YMMV.
I've found you need to go to the HP+ or similar street/track pads (see my post above about Powerstop Track Day pads) to get that wow factor. Last fall I did brakes on my daily and hoping to save some money went down a step form that level of pad, they were quieter, less dust but the performance drop off was significant. I ran them for the winter and may put them back on this fall but I ended up back with the track day pads in the spring as I wanted that performance and pedal feel back.
I'm sure the HPS 5.0 will handle autocross fine and on a car with better brakes to start with would be great, on a car where the braking system is a bit more marginal the better pads make a really big difference though.
In reply to adam525i (Forum Supporter) :
The hp plus were out of stock. I remembered you guys talking about the plus pads, and hoped that the guy knew what he was talking about. I will upgrade to the hp plus pads sometime.
As I said before about the cars screaming for parts, this car now appears to need new ball joints. I am also going to track down the deal someone was talking about on the brembo's.
I talked with someone from our local scca and he wondered if there would be rally cross later this season. If not, I will have money to divert to this car instead of my rally cross build.
@thedoc I can give you some tips. The fact that you recognize you are up setting the front end is huge.
You've probably learned the come off the brakes at the same rate as you wind in the steering already but I figured I'd throw it in just in case you hadn't. You know the drill, 100% braking then as you add say 10% steering you're at 90% braking, then 50% steering 50% braking etc until you are 0% braking and 100% steering.
If you have to wind in more steering after you've come off the brakes in order to get the car into the apex, you've very likely "popped" off the brakes abruptly and/or to soon.
Obviously the key is learning that muscle memory of transitioning from threshold braking to trail braking / trailing of the brakes. The good news is you can practice on the street. When you're coming up to a light as you get to the last 3-5 feet of the stop, see if you can bring the car to a stop without having the nose of the car noticeably pop back up. Additionally when coming to a stop, notice as you just come to a stop (last foot) there is a little tug so to speak. Try bring the car to a stop without that little tug, in order to do this you need to let the car roll an extra 6 inches. Once you have the feel for this, it will be like night and day.
You only need to trail the brakes just long enough to get the car to rotate into a corner, once the car's fully rotated and pointed at the apex you can come off the brakes. Any more than that and you are over slowing the car.
Being able to transition from threshold braking to trail braking/trailing off the brakes quickly and smoothly is one of the toughest things to master in a car. If you can master this you'll find, not only do you brake later but you'll also carry more corner speed. You may even have to take an event where you simply ignore your times and focus on nailing the technique. With any given change there is always a learning curve, it might be one run it might be two events, you never know until you make the change.
I suspect that at some point you'll need a brake upgrade but hold off on that for a while because as you've pointed out there is more in the car. It may not be a lot more but it's more. Keeping working on it and you'll get there.
This thread is somewhat relevant as we run front calipers from an '04 Mustang GT on our LeMons car. The car in question is a 1975 LTD chassis, so much bigger and heavier than the Mustang. We've tried Hawk HP pads and found them to not give enough bite, and to wear pretty fast. We tried the DCG pads (the 60's or 70's, I forget) and found them to be too "light switchy" and needing a lot of heat to work right. The Goldilocks pad for us was the HT-10- wore like iron, stopped great, easy to modulate.
Interesting to read about caliper upgrades that are bolt-on. One failing with the stock GT calipers is the OEM phenolic pistons. We've melted a few of them. Probably wouldn't be an issue for autocross, but definitely for a weekend long endurance race. Up to now we've simply kept a spare set of calipers on hand and considered them consumables. 
Other than that....stainless brake lines, Wilwood 600 brake fluid, bleed/ flush yearly.
Also- make sure to dial in your front camber. Too much camber can cause premature wheel lock up on hard braking. We've found about -1.5 degrees works best for our chassis.
Direct question: Are there calipers that are bolt-on replacements for the '04 Mustang GT, without requiring an upsized rotor?
In reply to volvoclearinghouse (Forum Supporter) :
I'm assuming you can't have a larger rotor per the rules? Check on rock auto, I think I remember seeing calipers with metal pistons. Although, plenty of guys are using stock brakes in American Iron and CMC so maybe you just need to get some fresh air in there.
In reply to thedoc :
I'm traveling today and tomorrow. I'll check and see what I can find Fri or Saturday.
2010+ GT Mustangs(non-track pack cars) came with 13" brakes which used the same calipers as the early S197 cars but different rotors, backing plates and caliper brackets. You can get the caliper brackets CHEAP, forgo the backing plates and just order new blank rotors off Rock Auto. Lines and all are the exact same.
This is a great budget big brake kit that works wonders for pedal feel and is large enough to handle light track duty.
or find a set of GT500 4 piston calipers and take off rotors. Its significantly heavier but they are a massive upgrade. I got mine off a wrecking yard for $650 and then bought most of the other stuff required - new pins, clips - on Rockauto.
Patientzero said:
In reply to volvoclearinghouse (Forum Supporter) :
I'm assuming you can't have a larger rotor per the rules? Check on rock auto, I think I remember seeing calipers with metal pistons. Although, plenty of guys are using stock brakes in American Iron and CMC so maybe you just need to get some fresh air in there.
I can't do larger rotors because we aren't running Mustang GT rotors...we're running OEM rotors from the 1975 LTD Landau. Bolt pattern is different, and finding larger dia rotors in the LTD bolt pattern is tricky. And then you have to deal with the offset.
We've already added venting to get more air in there. Might just see about switching to metal pistons.
In reply to Tom1200 :
Auto cross this weekend, I'll report back.
Guys thanks for all the input!
Interested in the results
