Upgrading to 11.75” discs on the front?
thanks blu i was expecting you to stop by lol. im only running the ssbc rotors, stock style brackets and calipers. car stops about as well as i can ask for manual brakes but seems like its lacking some, they arent really spongy that i can tell. im running a 1-1/32” bore master which i now discovered from reading and talking to cass at dr diff probably should have been a 15/16” bore but the pedal really doesnt seem that hard to press to me. Is the larger bore master hampering my braking? I know either way i need to correct my calipers being upside down and swap them side to side so i can get the bleeders at the top. I bled them off the car but due to not having the right hoses i had to mount the calipers upside down. They never have been bled since which was about 8 years ago so they may have developed a tiny air pocket. Either way i plan to fix the calipers by swapping them back to the correct position and order correct hoses. Im just trying to decide the best route. So is there really no need in going to drilled/slotted rotors on a street car?
So first off, yes, you definitely need to get the bleeders on the calipers facing up and re-bleed the brake system. That would also be a good time to flush out the old brake fluid and replace it, Demonic is right about that. Brake fluid will absorb moisture over time and it does need to be replaced.
So, using the 15/16" master cylinder would actually increase your brake line pressure, which will increase your clamping force at the calipers. If you use a 70 lb force applied to the brake pedal, consider the 6.5:1 pedal ratio on an A body, and calculate the brake line pressure with a 1-1/32" MC you get 545 psi. If you use the same applied force and ratio but with a 15/16" master you end up with 659 psi. If you take that through to the clamping force at the rotors using a 2.75" piston caliper, you get 3,236 lbs for the 1-1/32" MC, and 3,915 lbs of clamp force with the 15/16" MC, with everything else being the same. So the 15/16" master cylinder will increase your braking power and give a little more brake pedal travel, which will make the pedal feel easier to push.
As for the drilled/slotted rotors I wouldn't say there's
no need. It depends on how you drive your car and how hard you are on your brakes. If you do a lot of "spirited" driving on winding roads, or have a lot of long downhill grades where you need the brakes for long periods of time you might benefit from them. But I would say that the way most of these cars get driven most of the time the drilled/slotted rotors are overkill. Let's put it this way- if you've never had brake fade with the plain rotors, you don't really need the drilled/slotted rotors. They still might lower your brake temperatures a little, but if you're not getting to a place where you've noticed brake fade from heat they're not a "must have" item.
Brake fluid gets "stale" - rust, moisture from the air. Just freshening the fluid every 2 years can make a difference in pedal feel.
Many say that driller/slotted rotors are overkill on the street, unless you're road racing. If they don't get that hot, why reduce the contact area w holes?
Definitely agree with changing the fluid!
Although I would say most folks don't need the drilled/slotted rotors, I would also say that the area reduction from the holes/slots is pretty darn minimal. Like not really worth considering. You also don't need to be road racing to benefit from the drilled/slotted rotors, the brakes don't have to glow red for you to benefit from having the drilled/slotted rotors. That said, like I said above unless you're pretty hard on your brakes I agree they're probably overkill.
