Metric oversized calipers.

[Fox80]

It might have to be spread apart a little depending on the bore of the caliper piston, but more than likely it will still snap in. Also make sure while you have the system open try to get all the old fluid out. That is hands down the biggest reason for poor brake performance, soft pedal, and component failure.

 

[V8 Rumble]

This member did it and he had no issues. viewtopic.php?f=19&t=32495#.Ud3Vvcu9KK2

 

[Fox80]

That would be by far the high end of brake upgrades, like I said before unless you use your car for autocross events or something like that slotted rotors are just for show. If you have a big window in your wheel that you can see a lot of the rotor it would give it some eye candy but its a lot more money for just looks. That blog does give you a good look at the large bore caliper so you can see it does make them much bigger

 

[pontiacgp]

on the metric cars we raced we used manual brakes with stock calipers and rotors and performance friction pads. The rotors would be cherry after a few laps and we never had an issue stopping....

 

[buzz77]

This was a pretty informative thread. From what I see getting an oversized caliper with good ceramic friction pads is an excellent upgrade. Along with adding quality stainless braided hoses to eliminate a mushy pedal. Leaving the 10.5 stock rotor makes it an easy and cheap upgrade.

Also nice to see that both speedway and southwest (2 5/8 bore at southwest) carry oversized calipers that are much cheaper than the US Brake offered at Summit. With all said, im sticking with the stock caliper as I'm looking to keep the car original. A 301 v-8 doesnt require it. Besides I'm redoing the brake lines, bought pre-bent oem ones from inline tube for $164.00 shipped, and have Russel braided hoses. Should notice a difference from the rusty lines and dirty old brake fluid thats inside them currently.

Thanks guys!

 

[malibudave]

For the stock g-body braking system, most braking performance will be found in good, bedded front brake pads. Next on the list would be high quality, big bore calipers followed then by stainless steel braided flex lines.

In the past, I have purchased 3 different metric calipers for comparison for research in my manual brake conversion:

**CCP big bore 2.75" bore (2.565" piston diameter) metric cast iron caliper – WEIGHT 6 lbs 11.2 oz bare with slider bushings installed
**US Brake standard bore 2.5" bore (2.376" piston diamter) metric cast iron caliper- WEIGHT 6 lbs 4.7 oz bare with slider bushings installed
**Wilwood small bore 2.75" bore (2.704" piston diameter) metric cast iron caliper - WEIGHT 4 lbs 8.6 oz bare with slider bushings installed.

I first purchased NEW the $59.95 each, big bore calipers from speedwaymotors.com. There was some manufacturing issues or problems with these calipers and they sent me replacement calipers. The replacement calipers are NEW CCP big bore metric calipers. PN CP412526. Online, these are the same price of $59.95 each from classicperform.com. They look exactly the same except for the paint on the calipers. The originals where painted/powder coated silver. These are painted/powder coated black. The caliper housing, compared the standard bore US Brake 2.5” calipers and 2.0" Wilwood calipers, are a different casting. The piston looks to be stainless steel and comes with a dust boot installed. The piston diameter is 2.565" in diameter. These calipers came loaded with pads, slider bolts/pins, and hose fittings. You should be able to bolt these to your car, bleed the brakes, and drive. The piston cylinder side of the caliper is roughly the same size as the as the standard 2.5” bore caliper.

I have also purchased NEW, US Brake/Afco branded 2.5” standard bore metric calipers. They are $45 to $50 each online. The casting is not painted or powder coated. They come in a right PN 7241-9003 and a left caliper PN 7241-9004. They cannot be interchanged from side to side. The piston looks to be a cast steel/iron, unlike the CCP 2.75” and Wilwood 2.75” bore calipers with stainless steel pistons. They are also 2.376" in diameter which matches stock advertised piston/bore sizes. The casting looks to be a stock casting and comes with a dust boot installed. It has all the markings of a stock calipers. This caliper came unloaded with no pads, slider bolts/pins, and hose fittings. It does come with the bleeder screws and bushing inserts for the slider bolts/pins. You will have to reuse your slider pins from your stock calipers and hose fittings. You will need to purchase new pads or reuse the ones you have on your car.

I purchased NEW, Wilwood 2.75" big bore calipers to compare to the others. These are very nice calipers. The piston diameter measures 2.704 inches. On the underside of the caliper, there are ridges that bridge the piston side (inside) of the caliper to the wheel side (outside) of the caliper. These ridges are not present on any of the other calipers listed above. These ridges should cut down of caliper deflection. The weight of each of the 2.75" calipers is 4 lbs 8.6 ounces without the bleeder screw. The piston clearance is so tight with the caliper bore that there is no dust boot installed around the piston like the CCP 2.75” and 2.5” bore caliper above. These calipers only come with a bleeder screw. It does not come with any other hardware. You will have to supply the slider bolts/pins. All hardware should be able to transfer over from your original caliper.

Out of the three calipers above, I was most impressed with the Wilwood calipers. These calipers have a very clean casting that weigh at least 2 lbs each less than the other two calipers. These Wilwood iron calipers weigh roughly 1lb more than the Willwood comparable aluminum metric caliper with the 2.38” bore (4lb 6.4oz v 3lb 6.4oz). I run these on my 1980 El Camino with manual brakes, braided stainless steel brake lines, and good brake pads and have noticed substantial difference in braking performance over stock or the CCP 2.75" bore calipers.

You will have to upsize you master cylinder when upgrading to the Wilwood 2.75" bore calipers. Stock master cylinder bore size is 24mm. You will need to step up to at least a 1" to 1-1/8" bore master cylinder.

Caliper Specs

Caliper............................Part Number........Advertised Bore Size.......Actual Piston Size.....Weight
US Brake / AFCO Caliper.......PN 7241-9004..................2.50"..........................2.376"................6lb 4.7oz
CCP Big Bore Caliper............PN CP412526...................2.75"...........................2.565"................6lb 11.2oz
Wilwood 2.75" Bore Caliper....PN 120-8926...................2.75"...........................2.704"................4lb 8.6oz

 

[pontiacgp]

what were the braking distances of each brand of caliper?

 

[malibudave]

what were the braking distances of each brand of caliper?

I didn't test any braking distances with these calipers, but most of the noticable braking improvements will come from a quality brake pad. The calipers I actually used were the stock 33 year old calipers, the CCP "Big Bore" calipers, and the Wilwood 2.75" bore calipers. These were tested for braking effectiveness. The test were inconclusive because my original pads glazed over during testing of the stock and CCP calipers. There was noticable caliper flex in the stock caliper and the CCP "Big Bore" calipers when installed and the brake pedal pushed. The Wilwoods did not have any noticable caliper flex.

For my manual brakes I am running the a stock, 24mm bore, rebuilt, aluminum, 1980 El Camino master cylinder. This master cylinder barely gives enough fluid for the large Wilwood calipers. I need to step up to a 1" bore master cylinder. A power boosted system would benefit most from a 1/18" bore master cylinder.

I also upgraded to stainless steel brake lines and a Wilwood PolymatrixA pad. The PolymatrixA pads are a very aggressive pad for the street. But because I am running manual brakes with the small, stock, 10.5" rotor and with the small area of the stock pad, I went with the most aggressive pads. With a power boosted equiped g-body, I would go with a more streetable pad, especially if its just for cruising around.

 

[Fox80]

That post gives you a good look at what is available, the reason the Wilwood calipers look so much better is because a Wilwood caliper is made from a new casting. EVERY other brand is just an bored out stock GM casting core. The wildwood caliper is by far the best caliper made, but it is over double the price of some that are made. One thing to remember is it has pipe thread holes on both sides that takes special bleeders, and would HAVE to use a braided -AN line as the original banjo bolt will not work. However it does make them universal side to side, by just what hole you put the bleeder in.

These are the bleeders from Wilwood on ebay
http://www.ebay.com/itm/Wilwood-220-062 ... 37&vxp=mtr

 

[GuysMonteSS]

This member did it and he had no issues. viewtopic.php?f=19&t=32495#.Ud3Vvcu9KK2

That was me that did the above upgrade.
The brakes are still working great after 3 or 4 years now.At the time,I didnt know about the pro's & con's of the slotted/crossdrilled rotors,but they work great and seem to be holding up OK.I had them apart last year and the rotors and pads still look like new.
My Ford 9 inch rearend has way bigger drums than the Monte came with,IIRC,the drums are 1 1/2 inch bigger in diameter and the brake shoes are almost twice as wide.This combo works real nice,it stops a whole lot better than it did when I first got it.
Guy