aw614 wrote: ↑Fri Jun 24, 2022 11:17 am
Most of the braking is done up front and from what I recall, the Spoon twinblock was design to retain the same pedal ratio as the stock calipers. I know when I installed them, the pedal feel is similar.
Probably worth it’s own discussion but to share here:
Something that’s taken me awhile to adjust to on the track is that during threshold braking, especially on FF cars where weight is already forward of center, a car pitches forward and the load is transferred forward away from the rear wheels. This is more pronounced on street able cars with softer damping and thus less ability to control load transfer. Less load means the same crossection of tire has less traction, so the rear wheels hit the limit of traction before the front. Increasing rear braking force only means the rear will break traction and start to slide even earlier. You’ll actually increase stopping/slowing distance, unless you adjust the prop valve to decrease rear braking force. This is why you don’t generally see rear brake caliper upgrades for street driven cars and frequently see the use of more aggressive pads in front than rear and/or adjustable prop valves on the track. More serious applications even call for the prop to be adjustable while driving to allow compensation for changes to weight as fuel is consumed.
The only reason I can see rear brake upgrades making sense is in a situation where rear brakes are over heating and a larger rotor helps manage heat better. This is a common issue on heavily tracked S2000s where you’ll find use of extended brackets to move the rear OEM caliper further out to allow use with a larger rotor.
I feel like there’s a lot of misunderstanding around BBKs, with thinking that increased size (caliper/piston count/rotor/pad) delivers more powerful braking but that’s not generally the case.
For Integras (light car, generally considered well braked from factory) most bbk kits (Spoon and Mugen) keep the same OEM size pads or smaller and roughly the same total piston area. The kits reduce weight and improve heat management for more consistent braking. More aggressive braking is more typically achieved with more aggressive pads. Improvements to braking force with a bbk are generally indirect, in that better heat management means the ability to run more aggressive pads longer with less risk of fade.
It’s probably not something we generally want to hear but even oversized rotors create issues outside proper applications and also applies to running brakes ducting off track.
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https://www.brembo.com/en/company/news/ ... emans-2018
https://racingbrake.com/racing-pad-sele ... d-deposit/)
Peak braking performance occurs in a relatively narrow temperature band, defined by pad compound. (Understanding this is very very important to having a safe performance vehicle on or off track.) Issues arise not only when small rotors can’t effectively manage the heat load of aggressive pads, but also when large rotors are over cooled by available air flow between braking zones. This means pads and rotors will be outside optimal temperatures at the ends of long straights or during highway driving meaning reduced braking at peak demand. Also fluctuations in temperatures due too much availability cooling will also fatigue the rotor and pad material leading to cracking and failures. Understanding brake temperatures is very important to pad selection since a pad with too low a temperature rating for a given rotor and use will gum up the rotor surface and may lead to pad material breaking up scoring the rotor. A pad with too high a temperature range will have reduced performance when most needed at highest speeds as brakes are at their lowest temperatures.