Hi, if I install a dual piston caliper to my 1991 Camaro 3rd gen, I will have better braking.
I have found
https://www.rockauto.com/en/moreinfo...=5335&jsn=5335

 

I do not thinks so. My reasoning is the piston contact surface area is larger on the single piston. The 2 smaller pistons are less sq. inches than the one larger piston. The caliper size is the same so it takes more room for 2 pistons so they need to be smaller.

 

Looks like a 1LE caliper. It is an upgrade but requires some modifications and new spindles.

 

Yup; NOT a direct bolt-on. Not all that far from it, but not direct either.

Regardless, that particular part leaves you with a system that was only available in any significant numbers for about 3 years, was discontinued over 30 yrs ago, and there were only ever a few hundred (maybe up to 2000) TOTAL of them that ever existed. Finding replacement parts is a nightmare and won't be getting any easier. For EXACTLY the same money and EXACTLY the same effort and even EXACTLY some of the same parts though, you can put on the system we refer to as the "LS1", that came on all 98-2002 Camaro & Firebird. So you get a system that came on HUNDREDS OF THOUSANDS of cars, and is 10 yrs younger. Or even, some of the newer Vette / Camaro / CTS-V systems, if you really want to bite off.

Take a look at bigbrakeupgrade.com to get some further ideas and knowledge. I'm not endorsing his product but at the very least you can see what's available. Plenty of others on here have used his stuff and seem to have got good results, so I'm not recommending "against" it either, just, I have no personal knowledge of it. Note incidentally, he doesn't even offer the 3rd gen 1LE kit anymore.

 

Here's the ones I was referring to. This is listed as a direct fit for base model to Z28. As you see the 2 pistons are really small.

Cardone Industries Network 184343 Cardone Remanufactured Brake Calipers | Summit Racing

 

That's the 1LE caliper. Same thing he was asking about. Won't bolt onto a car that has the cast-iron ones now. It's only a "direct fit" to cars that came with the 1LE option.

 

The 1LE calipers are larger than the standard iron calipers, The iron caliper piston is like 2.5" OD and the two pistons of the 1LE calipers total are like 3", the 1LE calipers physically are also aluminum so they dissipate heat better than the iron calipers, all in all a pretty good upgrade. As it's been previously stated they are not a direct replacement for the iron calipers.

 

The biggest advantage of the 1LE system though, and all those that came after (LT1, LS1, C5, C6, yadda yadda yadda) is the ROTOR size. The number of pistons is almost incidental, a sidenote. The thing that makes them SO MUCH BETTER is their larger rotors. There's NO difference in brake performance among systems with different numbers of pistons, except to the extent that the pistons can all press on the pads. Which is to say, if you had a piston that was 1 sq in, vs 3 that were 1/3 sq in each, there would be NO DIFFERENCE in ultimate performance, except that the size of the pads might not allow a piston that large. It's all about SQUARE INCHES at that point. X psi in the fluid, pressing on Y sq in, yields Z lbs, no matter how however many pistons divide up the area.

THIMK: the rotor hub, the center and the bearing zone, is pretty much the same size, no matter what, for any given car model. BUTT: it the rotor is larger, it's larger toward the outside edge. That means it has a larger area (duh) which is a function of the SQUARE of the dia change not the dia itself, is farther from the center therefore has greater mechanical advantage over the car the tires and whatever else, and it can cool better. THAT'S what makes these systems better; NOT, the number of pistons. The increase in rotor dia has an effect close to THE CUBE of the difference: so for example, from the 10.4" dia of the old cast-iron system (which was THE SCHIZNIT in the late 60s when it came out) is 10.4" more or less; the rotor dia of the LS1 system is 12" more or less; that's a 15% difference, more or less, which might not seem like a whole lot; but the CUBE of 1.15 is over 1.5, meaning with NO OTHER CHANGES WHATSOEVER, you're already at a braking system that's about half again as efficient as what you've got now. Butt then you get the better cooling too, which means they keep braking FAR longer than the little weenie 60s brakes you have now,

That's what makes brake upgrades so powerful. It's almost like compound interest, except you don't even have to wait. It compounds INSTANTLY.

 

To add..
Multiple pistons, like mentioned can be spread over a larger surface area, larger rotor = more leverage,more mass- more pad surface is more friction. The one thing not mentioned about dividing that sq inch area up into more than one piston is the speed of the pistons. The larger single piston is going to move at "X" rate with the given amount of fluid displacement, divide that in half for example (2 piston) each of those two pistons will move multiple times as the single one did, multi piston brakes react to input faster than a single.. Who here who has owned a stock brake 3rd gen not felt that panic when something in front of you occurs and you hit the pedal and hear swoosshh...and wait until you get past the low pressure high volume portion of the two stage master then unto the high pressure stage to finally start the braking. These cars were the worst brake`ers out of all the lines of GM that got the same exact parts...the others did not get blessed with that POS master and non functioning prop valve. Drive a S-10, 78-87 G body anything besides a 3rd gen with the same brakes and you instantly find that they were not as awful as they were on the 3rd gen platform.
I actually never offered the 1LE`s, they did not really offer a great leap in performance as I would have expected (personal experience) The LS1 swap is a night day dramatic difference however

Hydraulic comparison @ 70 bar

40mm bore w/ 25mm of stroke @ 1 LPM would equal .093 seconds
80mm bore w/ 25mm of stroke @ 1 LPM would equal .372 seconds