I have a set of Powerslot rotors on my 95' TA, they're cool and all but would look 10x better if they were both drilled AND slotted.

I was thinking I could just make a templete using a per-drilled and slotted rotor as a mock -up. I could just use a sharpie marker to dot the spots to drill, then drill away!!!

What do you guys think???? Has anyone done this????

 

You can do it, but it will only last a little while before they crack all to hell and back.

 

Think, STRESS CRACKS.....

 

Gee, thats what all the drilled rotor vendors do- Just drill out other manufacturers rotors- they don't all crack. If the two of you above me are so knowledgeable and experienced on this subject, then maybe either of you could post pictures of rotors that have cracked on you in the past? Only happens with extreme heat racing conditions- Conditions that can noit be duplicated on the street, unless you are on the news involved in a police car chase and blatantly disobeying all laws and stops.

They can be drilled on a press with the proper hold down, Hole must be camfered though.

 

Another thing I should note to be safe, Make sure BEFORE you drill any holes that you have marked a complete patren on the entire rotor and that each drill will be centered on an individual vent. also pattern need to altenatecontact with pad surface area insuring that all pad surface is covered evenly throughout one rotation. It alot of work to do it right. the companies that do it have computer programed machines.

 

yeah, I wouldnt do this without using a CNC drill press or something like that

 

Your first post makes it sound like you want to grab your electric drill, a bit, and start drilling. Done properly--like the manufacture of drilled rotors do it--would be fine. I wouldn't say they are just 'drilled', I'd call it machined. Machined to prevent stress cracks witch will occur if you just drill them.

 

Comparing drilling stock rotors to the way baer and powerslot do it is like night and day. The biggest thing is the material the stock rotors are made of suck. Its to brittle. Here ya go AGood2.8

 

1)Holes weren't camfered
2)Your pattren covered cicular paths leaving hot circles where pad heat is constant- notice your grooves running entirely through both drill sets and not ever intersecting with a dimple.
3) whats with the doule hole pattern on the one rotor- oops
4) where you running carbon/ceramic pads- most likely not- common mistake to use hard semi-metalic pads. They will heat spot /glaze much easier.
5)and the rust? was your car stolen and dumped in the ocean?

Yep, typical misguided person tries it wrong, then tells everyone else it can't be done.


Thanks for your imput, we'll chalk this up as what not to copy.

 

Those holes are WAY too big. Probably 1/8" is plenty.

You can mark them up and just go to town on them. Dont worry too much about spacing to the nth degree nobody will ever notice, just get it close. I marked a circle on mine by mounting the rotor to a mill (left the bearings in), lined it up somewhat close, brought the tip of the drill down to the rotor, and turned the rotor. Real hard. You could feasibly set something up on the car using the caliper mount and a pen to mark a circle. 1 hole per vent is more than plenty. Trust me, you do not need 2.

I'm still waiting for the cracks, I'll bet they never come.

 

#5 - EVERY car around here has rust covering every part of the rotor that isnt a friction surface. When you do your brakes, you can see the rust scaling off the vanes of the rotor... Its called the salt belt. It loves bare metal for lunch.

 

Yes that i understand, you friend are in Michigan, he's in sunny Florida.

 

well, just don't drive near me guys! I don't car what you say unless you have some real testing then I think I would pay the big bucks and get some from bear or so. If you hit and kill some one and after they determine the rubber is ok and the investigate further to find out you drilled your rotors... it won't matter if they failed or if you just had a slow reaction to braking you won't be buying anything new for quite some time. and I don't think you will have an insurance company anymore

 

Not mine. I don't drive most of them in the salt, and prime/paint the rotors before installation. Then again, the entire underside is painted, except the driveshaft and exhaust. Steering rods, swingarms, springs, calipers, frame channels - everything.

 

pics?

 

What's the point??? It won't make the brakes work better one bit and I will gaurantee you that they will crack when pushed. Been there, done that - with supposed properly done rotors too. The only way to have a drilled rotor survive when pushed hard is to have one that was cast that way to begin with. Drilling the metal just disturbs the natural internal structure of it and provides a place for cracks to start.

Some of you people in search of better brakes really need to take a close look at what kind of pad you are running because pads mean EVERYTHING!

 

They look better when drilled & slotted....

 

id listen to Agood2.8L on this, its quite obvious hes extremely intelligent with this stuff. im doin the 1LE brake conversion on all four corners and bough slotted rotors, i figured for teh driving i do even the brake upgrade alone is more then i need. i guess id plan out how the car is gonna be used before goin crazy with the brakes.

 

Mine hasnt cracked, and shows no signs of doing so. First 2 times I had that car out, all I did with is was carve up canyons. Under minimum thickness too.

Sounds like a bunch of paranoia to me.

"What's the point???"

I was bored and my rotors are shot anyway?

 

I will share with everybody a secret I learned many years ago about playing around with drilled and sloted rotors, and different pad combos (here goes my big secret- this is priceless info that will help with anyone performance driving)

Drilled rotors help with initail bite. What this means? Brakes will come on faster because of reduced pad float and gasing (gasing is really determined by the type of pad used :material and heat range.) When you run drilled-only rotors on the rear (Has to be the right pattern -See picture below- six radius drill patern. covering entie pad surface at properly spaced offset intervals), It will give the entire chassis a better controled weight transfer under hard braking. I'll explain-

The back brakes come on faster first (initial bite) than the fronts(fronts I run slotted). When pressure builds from the brake pedal "stomp", the front brakes will begin to come on stronger like they are suppose to- only a split second more gradual. This takes away a tad bit of the car standing on its nose and the *** end getting loose. {now you can control this better through higher rear rebound sttings on the shocks- but this will also hurt you the same amount in the corner as it does help you transitioning into the corner.} When you pedal the brakes as hard as you can without locking, the fronts will slow down harder than the rears because of lack-of surface area on the rear rotor and prop valve bias. This is just the rotor part!

O.K Here's My Secret combo- What rotors where with what pads where- this is what balances things for me and really makes my car tick ( this was developed through trying numerous different pad combinations)

Powerslot front rotors with Stillen carbon matrix pads

Stillen drilled rear rotors with EBC redstuff pads in the rear (Note: old picture- pads in pic are Stillen I think, not EBC. I also run Koni's now.)

My car trailbrakes basically by itself with the combo I have combined with MY weight bais, prop valve, shocks, suspension, and tires. This will not work on everyones car.

Reason I posted this is to give a great example of what benefit can be gained be the use of DRILLED rotors- They are not always for looks- if drilled correctly.

 

I should also note that the combination I run, and only being 10.5 " iron caliper setups, will consistantly put you through the windsheild - Repeditively- stop after stop after stop, with out fade. The actually even get stronger with heat. The only problem I have is that the tiny rotor diameter is much more tempermental because of the extra heat it induces from its size- and after a very hard day of autocross, the rotors will start to warp. Over the next few weeks they go down hill fast and I have to pull'em and turn 'em- then I am fine till the next real hard go round.

I have never had a problem with heat under the hardest street driving- only after autoX. I'd hate to see them after road track time- I have passed up 3 chances aready to take this car onto California Speedway inner roadcourse and 1/2bank.(car lacks power for this highspeed stuff also- I leave this for my 540hp '68 Vette.)

 

Interesting what you can do with the small 10.5" front barkes. Now I have a 1986 Camaro that I Autocross and Hillclimb. Extremely modified car and very fast. 1LE rear brakes but currently, only 10.5" factory brakes on front. I run Bendix Titanium pads up front. I run an adjustable proportioning valve and crank a lot of brake to the rear. This combo can consistantly out brake full factory 1LE setups. Has no problem at all hauling the car down from 110mph + at hill climbs. Plus it stops RIGHT now when the pads are cold. Have tried other brands, such as Raybestos ( absolute crap in my experiences ) and PFC ( don't have the cold stopping power of the Bendix ), but nothing beats the Bendix TI brand for street and Autocross \Hillclimb work IMHO.

Two years ago I decided to re-new my Senior Race Drivers license. Two days of racing. I ran a half hour Novice race, a half hour Senior GT Race plus all the qualifying and practice sessions, Saturday and Sunday....all on the 10.5" brakes!!!! On a track that is notoriously hard on brakes. Impossible...not really. You just have to understand the problems and have good preparation.

1) Ran Hawk Racing Blue pads. Not the best in retrospect, but cheaper than PFC and got the job done.

2) Motul synthetic brake fluid....this was very, very important. A mineral fluid would not have worked at the temps we ran.

3) Tons of air ducting to the brakes with 5" x 6" rectangular scoops beneith the front airdam.

4) Full synthetic grease in the wheel bearings. Mineral grease would have failed at the temps we ran.

5) Water sprayers to the brakes actuated from the horn button. This was one of the key things that kept the brakes alive. That and the synthetic brake fluid.

The whole weekend the brakes were rock hard. Never boiled the fluid. Only in the GT race when I was in a battle for fifth Overall did the brakes start to fade a bit. I would use the water sprayers before and after every hard application. You could actually see the steam coming off the front brakes when the water was applied.

The corner workers from the hairpin came to us at the end of the day and told us they could see the front rotors GLOWING in the daylight!!! From that we estimated rotor temps to be around 1000C centigrade.

Inspection of the brakes revealed the following. Rotors were absolutely toast of coarse. That was to be expected. The outer tie rod boots were melted away from the heat. The Amsoil synthetic grease held up fine. No problem at all. Now the brake pads....that was interesting. The brake pads had gotten so hot that they had expanded and the outer edge of the pad seized on the carrier. The backing plates got so hot that the pressure from the caliper piston actually BENT the pads!!! Only about 50% of the pad was actually touching the rotor at the end of the weekend. Fellow racers could not believe there eyes...the whole pad had about a 1\4" bend in it. Except for the degradation in performance during the last race ( understandable given the condition of the pads ) the brakes worked amazingly well. Wish I still had a pad so that I could show you pics

BTW, a new system is in the works. 12" x 1.38" Nascar 48 vane rotors with WilWood hats and Superlite II 4 piston calipers. All done ready to bolt on. Will post pics as soon as I can.

 

Very nice posts. I ran Wilwood Bs with my 10.5s and I was indeed absolutely amazed at how well they performed. Just a night and day difference in pedal feel and power... That is, right up until the rotors cracked all to he11 (definately a rotor issue). I ran those Bs with PFC Zs in the back (11.9s from an LT1 4th gen) along with my adjustable prop. valve heavily cranked to add rear brake bias but had some awesome results while road racing. I definately do need to run some ducting, but I think a quality solid rotor would have faired much better. You just don't see any of the serious guys around here running anything but a solid rotor.... And the ones with drilled rotors are using rotors that were cast with the holes integrated into the mold (meaning the grain is undisturbed). Only problem being the price involved in something like that.

I am working on a system using the very same rotors and calipers myself, Chickenman35..... I am working with a friend of mine and avid road racer/Wilwood dealer on a kit that will use an AL hub with a slip on C4 sized hat with those rotors and calipers.... From what I have seen the Js seem to be the pad that will suit me the best. They come on a lot faster when cold in comparison to the As and Bs and have nearly as much torque when warmed up. Those and maybe some Ds for the street.

The design we are working on for the caliper mounting is going to use the strut through bolts with a CNC'd beefy hunk of T6.... What have you done about mounting the caliper on your design?

 

Powerslot front rotors with Stillen carbon matrix pads

Stillen drilled rear rotors with EBC redstuff pads in the rear

How long would a setup like that last on the street? I'm assuming not too long, but I figure it won't kill me to ask.

 

Whats up with the fighting? O_o but anyways yea I think if you just do it RIGHT then it'll be okay especially if your only gonna be using the car ont he street.

 

It seems you are pretty made up on this. Just drill them and see for yourself. However, no one in this site can be held responsible if anything happens to you and your car. Remember, your brakes are a safety function. If you do something that puts you, or others at risk, its your fault.