Drano38

After hours of searching/reading, I'm getting smarter on brakes for my 2010 GT. I plan to do autocross and a 4-6 days on Mid America Motorsport's road course each summer.

I plan to get Carbotech pads (Bobcat for street, and swap to XP8/10 for the road course). Seem to be good for street/track switch w/ manageable dust and low noise. Super Blue fluid also seems to be a great choice from reading here.

I want to buy rotors to have a spare set on hand (and lets me drive the car when a set of rotors is getting turned).

Should I get NTO rotors, or NAPA (or any other parts store) rotors? I'd guess store-brand are about the same quality as factory rotors.
I'd turn the NTO rotors because Carbotech says thats required before their pads are used, and I don't want to risk contaminating the pads.

NTO are $90 a set plus ~ $20 to turn a pair= $220 for 4
NAPA "premium": $45 front, $43 rear (each) for their basic rotors w/ quoted .004" runout= $176 for 4
NAPA Ultra Premium states .002" runout at $75 & $53 each = $256 for 4

So which would you guys recommend? What is the typical runout of a turned rotor? If a shop can't do better than .004, might as well buy new?

Advice greatly appreciated.

allinon72

Get the stock take offs for sure. Rotors at Napa, no matter if they are "premium" or not, are cheap rotors made overseas.

Argonaut

I think when starting out there is a tendency to make to much out of this stuff. I know what Carbotech says...but I've used their pads a lot. I've never had a rotor turned and I've swapped pads probably a hundred times. With Carbotechs the key is in bedding the pad, they are the most fussy when it comes to proper bedding. I have had severe vibration due to miscellaneous pad deposits and going out and doing a good bedding process has cured it every time.

Carbotechs are great pads, no doubt. But, there are other great pads out their as well. The Ferrodos aren't nearly as fussy about bedding for example and yet still work well.

To answer your question specifically, here is what I'd do: get both sets of CT pads. Put on the bobcats, go out and do a quick simple bedding. Do your daily drive. Use them for AX as well, they will work just fine. A day or two before your next track event, put the XPs in. Then do the full bedding process (they come with instructions). Let them cool. Drive again, if you have vibration, do another full bedding. Go to your track day. When you get home, put the bobcats back in...no bedding needed. Prior to next track day, put the XPs back in and go try them out. If you have vibration...bed them again, it will go away.

Regarding a back up set of rotors - I'd get the NTOs. Then, at some point, I'd put them on and use them with the bobcats as my daily drivers. This "seasons" the rotors, gets them use to the heat-cool cycle. They will last longer than if you just slap them on and then hit the track. Once seasoned, you can just leave them on and use your current rotors as your backups.

The alternative is to use one set with the bobcats exclusively and the other set with the XPs only. Then you only ever need to bed once. But the drawback is it takes more time to change rotors and pads vs pads only.

Here is a good article on swapping street-track pads: http://www.essexparts.com/learning-center/swapping_pads

Alec

I bought my rear rotors from NTO. No complaints

Sleeper_08

I just bought a new set of rear rotors from a Ford dealer and they were made in China. Up here in Canada the Ford ones were about the same price as the NAPA ones.

The set of GT500 fronts I bought last year were made in Italy.

DPE

Just was up at MAM last Friday with my 2010 GT. Hope to see you out there one day! Anyway, my 2 cents on this having just been through what you are going to go through...

I've run LOTS of ATE fluid in my day, but for a car as relatively fast and relatively heavy as the Mustang, I'd go Motul RBF600 (which is what I did). It just can't hurt. I had zero fluid issues and haven't even bothered to bleed them since the track day and the pedal is still high and firm. It's just better, and I think less compressible so you get more consistent feel. ATE is good and will do you fine, but Motul is just better. Carbotech carries it, just FYI.

Safe to say you'll get OEM rotors over NAPA Premiums; I think that wise.

I switched from the OEM Performance Friction pads to XP10s/XP8s, did a light bedding on the street, did a pretty calm first session with early/moderate braking, let it sit for 40 minutes between sessions, and then went for it after that. Zero issues with brakes. Swapped back today and drove around, and while the OEM pads feel lame compared to Carbotechs, they seem to be working just fine. I wouldn't lose too much sleep over swapping rotors etc. Can't hurt, and I plan to go that direction up front eventually just so I have a set of decent rotors for street use that aren't all cracked and crappy, but for this first event I was fine.

Only caveat is that I have a Boss/CS airdam and a Ford brake cooling kit installed (hooks up to that airdam nicely); I have to believe that helped more than a little in keeping things cool and operating efficiently. Zero fade all day. Also running Sumitomo HTRZ IIIs in 275/40 on GT500 wheels. Quite superior to the OEM all-seasons, but not exactly R-comps either.

Okay, one more caveat: First time on track in this car or anything like it. I have over 3000 track miles under my belt, but never in any kind of muscle car. So take inexperience in a new car with 1500 miles on it combined with a cool and occasionally muddy track surface last Friday (some folks were REALLY clipping the apexes!) and I wasn't exactly running 11/10ths all day. Just some of the day . That said, the car is really good out there. Much better than I expected, honestly. Very consistent. Needs shocks (you'll agree after turn 4) and more negative camber up front, but with decent tires and a proper brake setup you can certainly go out and have some fun.

Phil
2010 GT

JAJ

How did you get the duct past the windshield washer fluid reservoir? I pushed my hose (I have the Quantum Motorsports kit) through the gap between the bottle and the AC pipe, but that rotor ran 50 degrees hotter than the other three all day. And, it was 50 degree weather with a green track that hadn't been used since last fall. When the track gets hotter and faster, I'll need more cooling on the RF corner. What does Ford say to do?

BTW, I'm using Motorcraft DOT3 fluid and PFC-01 fronts and PFC-97 rears. Car slows down and trail brakes just fine - good balance, good modulation. If I change fluid, it will be Castrol SRF. You can run it for a full year of track days without changing it, so it's actually cheaper than Motul by quite a bit. The Ford fluid is even cheaper, but has to be fresh to work properly, and the jury's out on compressibility. The brake pedal has more motion than I like and heel-toe is a bit of adventure at this point.

DPE

JAJ, I had no issues getting around the washer fluid bottle. I thought I was going to, but the hose in the Ford kit is very flexible and just makes a hard turn around it. Nothing particular about it in the instructions for the Ford kit; just route the hose through there is all it says. It stays pretty 'round' through there too.

That said, I didn't check rotor temps so I have no idea if one was running hotter than the other. Seems like it wouldn't matter; yeah the air has to make a couple extra turns on that side, but it's not as though it's notably 'restricted' given it's just flow-through air and not under pressure like exhaust gasses or the like. Maybe the turbulence created by the bends disrupts it a bit though? Not sure what track you were on, but if you trail brake a lot and were on a counterclockwise track I wouldn't be surprised to see your RF rotor run a little hotter.

Phil
2010 GT

Drano38

Guys,

Thanks for the great responses. I've got front and rear NTOs in the front porch now. And today I picked up a rear brake piston kit to easily push the rear pistons in.

Pads--lots of choices, none are perfect. I've tried to call Carbotech, but the sales reps are always on the phone, and I miss their call-back. Hope to catch them Monday morning. I'll most likely get a set of Bobcats for street and XP10/8 for track use. I'm sure Hawk makes a nice pad for my uses, but most stuff I've read says their dust can be more severe on the wheel finish. I hope to keep the car detailed between track days, so that's a factor. I'll Poorboys wheel wax the wheels when I put the pads on so that should help.

Unless the Carbotech rep talks me into Motul RBF600, I'll get ATE Superblue. I've never driven a track, so I will be starting out easy and carefully building from there. Maybe next year I'll step up to Motul when I'm driving harder.

After I get back from the first track day, I'll decide on brake cooling. CS lower fascia would make an easy hookup, as do a couple other options. Not sure why the CS air splitter is so outrageously expensive. Obviously I'm missing something.

Once I get the brake system setup, I'll add a CAI/tune, then move on to suspension. So many toys, so little time.

Thanks again for the help.

JAJ

Interesting - thanks, Phil. I didn't have a problem getting the hose around the washer bottle, but I think the air finds it challenging. It is a very technical (trail braking a lot) CCW track and it's the front outside corner, but my no-ducts-at-all BMW M3 had no meaningful temperature bias from side to side at the front or at the rear. This one was consistent every time I came in for tire pressure checks.

I've bought a spare washer bottle and I'm going to look at relocation strategies - heating and bending or something like that - to create more clearance.