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After lots of research I finally decided on the Hawk HPS brake pads I followed the bedding process to a T and after mayebe 15 mile of driving I have about a 1/2 groove in my rotors.
What brand of rotors are you running? I ask because some of the rotor packages sold on eBay or other online sources are soft cast iron and wear very quickly. I replaced rotors and pads with Centric OEM equivalents and they bedded in nicely with no grooves like in your pic. I know slotted and drilled rotors look awesome but they’re really not necessary except for some racing applications. There’s tons of info on the net about brake systems. Also, the groove you mention is where the pads do not contact the rotors. Good luck.
Last edited by Roys92BlackRose; 08-10-2018 at 05:02 PM.
I;ve had HPS on my wife's stock CTS'V rotors for years. Same rotors. I would get some good rotors...then decide. NAPA Ultra Premium are a great rotor for decent price.
If those grooves where not there when you installed the pads, I'd say the rotors leave much to be desired.
For ALL street driving, including some spirited mountain runs and autocross stuff, it is hard to beat the stock cast iron discs. My stock (J55 ZR-1) rotors look like new - sans grooves - and they are wearing HPS pads now, and I've got another set waiting to go on after my 4th mountain run. Love um! They dust a bit, but that is just the way they work. Pad material sloughs off w/ extreme heat instead of the cast iron.
Slotted rotors of good quality are expensive, and drilled rotors (good ones) are VERY expensive. I have a friend that spends $1000s on brakes (for his track car) and has recently has gone away from drilled/slotted rotors in favor of plane ol' cast iron all together. In his garage he has boxes of trashed drilled/slotted rotors - purple from the heat, and every one of them has CRACKS radiating our from the drilled holes, EVER ONE of the drilled rotors, and what is left of a rotor that disintegrated after cracking while in the "heat of battle". Good ol' cast iron for me! And, I can go through a set of rotors in 10,000 miles - no problem - and have done so. (But, I haven't had to change rotors yet, except when I bought the car - one rotor was gouged b/c the pad rivets had gotten into the rotor before the pads were replaced.)
I'm a WARRIOR, Drilled/slotted may look sexy, and even less expensive ones can last a good long while if the car isn't "tracked", i.e., a WAXER's dream. But, unless they are titanium or some other exotic material, they are mainly for looks ONLY, IMO.
That looks like a rear rotor. The rear caliper (and pad) rides high on the rotor a doesn't make full contact with the machined surface.
SAE J46 schedule for brake burnishing is 200 stops from 40 mph to zero at 0.3 g decel starting with an IBT of 100 C or maximum of 1 mile between stops. Even after 200 stops, complete rear pad contact and material transfer can be sketchy. Due to the speed and number of stops involved, this procedure takes about 4 hours to complete. Despite what Hawk recommends, 15 miles is not really sufficient, especially at the rear since you never really get much heat in the rear pads.
After lots of research I finally decided on the Hawk HPS brake pads I followed the bedding process to a T and after mayebe 15 mile of driving I have about a 1/2 groove in my rotors.
I have Hawk HPS pads on my C4, there are no deep grooves.
They do wear the rotors more, but that is what i expect with a high friction compound.
If you are talking about the GAP between the brake pad contact area on the disc, that is around 1/2 inch that is not covered that is normal.
I can see your brake pads are wearing the normal area for a C4, you have a 1/2 inch gap and a thin 1/8'' gap at top which is perfect.
It only shows up because of the cross drilled / slotted rotor area, you would not notice on a plain disc rotor.
I have the same type of cross drilled and slotted rotors with same brake pad swept area, nothing wrong with that the further out the caliper is the more leverage.
That is why they are in that position, i know some other cars use a brake pad that covers the entire disc surface.
Inspect your old brake pads compared to the new, there is no room for more friction material on the metal surface?.
I have had a look of my before and after pics standard compared to cross drilled, with the 13 inch rotors there has always been a 1/2 inch gap.... See if anyone else can post their pics.
Here is a GEM of an article that has completely re-aligned my long-time beliefs regarding brakes - AND has saved me hundreds of $$ over the years on unnecessary rotor purchases and re-surfacing (turning), etc., etc. Fact is, there is SO DAMN MUCH misinformation and hype out there - that it is no wonder we consumers get fouled up when it comes to brake maintenance.
Anywayz...long as we're talking about brake pads and wear patterns, etc., I thought y'all might be interested in reading this. Thanks to this ONE article, a plethora of myths I carried around with me for decades were dispelled - with IMMEDIATE positive results. The article is one of my favorite AH-HA pieces of important truth info. See if you agree!
08-10-2018, 04:19 PM
Disappointed with new Hawk brake pads
