ZL1 rotors

[Camaro21]

Originally Posted by jessrayo

I'm curious if the air vents in the center of the rotor pass straight through or are curved. Could you post a pic of the rotor from the outside edge? Those are clearly 2 piece, the only other difference the brembo had vs. the original GM was the Brembo rotors had a curved air path between the two rotor halves. The longer curved air path gave more cooling and made a big difference in heat management at the track. That is one heck of a deal if they are as good at the track.

Here is the pic.

[toehead93]

Originally Posted by jessrayo

The stock front rotor was designed by Brembo. It was a replacement for the original one piece in the CTS-V. The stock brembo is a very, very good rotor and about 5x better at cooling than the original one piece. It has 80% of the features on the racing brake rotor (no slots). If price is a concern, I would find a discount price on the stock 2 piece rotor. I would never put a one piece rotor on the front of a ZL1. If you want a little better cooling and a little less weight go for the Racing brake rotor.

That is interesting information. Is there an old GM press release about the differences anywhere that you know of? I've always heard the zl1 rotor was more efficient with heat but 5x better is pretty good.

[jessrayo]

Originally Posted by Camaro21

I bought my ZL1 used last September and Lou Gigliotti with LG Motorsports owned this car before me and it was apparent that he tracked the car and has heavy grooves in the rotors and they squeal BAD !!

If the brakes are squealing it is probably because he had racing pads on the car, my racing pads squeal like crazy. The best pads for stopping make noise...there comes a point where either you have consistent stopping no matter how hard you push the car and the brakes squeal at city speeds or the brakes fade at terminal velocity and are quiet on the street. Most serious road course drivers don't care if the brakes squeal. I have gotten very used to it. It just reminds me I have race pads on the car.

If you have no intention of racing the car you probably could have the rotor resurfaced and put on a stock pad or even a ceramic pad (less dust). I suspect you may have plenty of material left on the squeeky pads.

Thanks for the rotor information.

[jessrayo]

Originally Posted by toehead93

That is interesting information. Is there an old GM press release about the differences anywhere that you know of? I've always heard the zl1 rotor was more efficient with heat but 5x better is pretty good.

That is my personal estimate based on my experiences with the CTS-V I was running on the track. Due to the mass of the car and the horsepower, brake problems ended many sessions. The ZL1 had not been released at that time and originally the only option for the CTS-V was run the one piece GM rotor or swap out calipers and everything to something different. I literally spent around $10K trying to get that Caddy to stop no matter what I threw at it. When I swapped to the Brembo 2 piece rotors with longer air channels in the rotor everything else worked fine. No more melted pads, boiled fluid...etc.

I destroyed two sets of one piece rotors, about 4 sets of pads, had to switch to braided lines, ran large custom brake air vents and when I put on the Brembo 2 piece rotors everything else fell right in line and no more problems. I looked them over thoroughly and noticed the air passages were not straight through. If you run a string or wire through the air vent between the 2 halves it is more than twice as long as a direct path.

When I say 5x that is probably an exaggeration, I have no technical data to support that. But the exact combo that never had a brake related issue on the CTS-V is the same combo I ran on my ZL1 with 200+ more horsepower and no issues at all. Caliper paint has been burned off and the rotors have heat cracks all over them but the brakes have never faded an iota.

[jessrayo]

Originally Posted by Camaro21

Here is the pic.

That is a good rotor. Good find. Thanks.

[Stephen12ZL1]

amazon says 1-2 months for the rotors to arrive that is $100 cheaper each than the other vendors...what was the ship time?

[omegaman]

Originally Posted by Camaro21

FYI,

I just purchased both front AC Delco Rotors and AC Delco Pads from Amazon for a total of $680 Shipped.

Left Front Rotor Part # 177-1145 - $233.54
Right Front Rotor Part # 177-1146 - $219.29
Front Pad Kit # 171-1040 - $175.78
plus taxes

Great find! Thanks for sharing the part and pricing information, along with the numerous pics.

[Camaro21]

Originally Posted by Stephen12ZL1

amazon says 1-2 months for the rotors to arrive that is $100 cheaper each than the other vendors...what was the ship time?

Originally Posted by omegaman

Great find! Thanks for sharing the part and pricing information, along with the numerous pics.

I guess I was just lucky to find them when I did, they had 1 each in stock. Because I am a "Prime" member, I got them in 2 days.

[JB12ZL1]

Chrome brakes rotors for zl1 are one piece and weight slightly less than oem they told me.

[BaylorCamaro]

Originally Posted by Camaro21

FYI,

I just purchased both front AC Delco Rotors and AC Delco Pads from Amazon for a total of $680 Shipped.

Left Front Rotor Part # 177-1145 - $233.54
Right Front Rotor Part # 177-1146 - $219.29
Front Pad Kit # 171-1040 - $175.78
plus taxes

Originally Posted by jessrayo

I'm curious if the air vents in the center of the rotor pass straight through or are curved. Could you post a pic of the rotor from the outside edge? Those are clearly 2 piece, the only other difference the brembo had vs. the original GM was the Brembo rotors had a curved air path between the two rotor halves. The longer curved air path gave more cooling and made a big difference in heat management at the track. That is one heck of a deal if they are as good at the track.

Not to necro a dead thread, but is it confirmed that these AC Delco P/N's are indeed a direct replacement? I track my car regularly and I want to make sure that they are the same rotors that come OEM on the ZL1. Since Jess pointed out significant cooling issues with other designs I want to make sure I get the correct rotors.

[jessrayo]

The pic he posted in post number 43 is the curved air passage design. That rotor is as good as the stock one on the ZL1. I think the racing brake rotors resist cracking a little better but the price is a lot more.... at this point I would probably just buy those.

[BaylorCamaro]

Originally Posted by jessrayo

The pic he posted in post number 43 is the curved air passage design. That rotor is as good as the stock one on the ZL1. I think the racing brake rotors resist cracking a little better but the price is a lot more.... at this point I would probably just buy those.

Kind of what I was thinking. My stock rotors lasted me 4 very hard track events + a couple autocross. They probably have enough life for 1 or 2 more track events and then I will definitely need to replace them.

[ZED SLED]

Originally Posted by BaylorCamaro

Kind of what I was thinking. My stock rotors lasted me 4 very hard track events + a couple autocross. They probably have enough life for 1 or 2 more track events and then I will definitely need to replace them.

Nice avatar Just ordered a similar t-shirt

[Jeb114]

I thought GM and Brembo designed these brakes to be the best they could be. Seems to me it would be a downgrade to change from OEM. You want better put carbon fiber rotors from the Z/28 if they fit?