Brake calculations OEM vs different rears

[frankc5r]

As others have noticed, the way FFR has you do the brakes with the prop valve on the front so you can reduce their performance to match the small rears that now have to deal with
60% weight is not the best way. Wayne P has gone to 12.88 Wilwood rears with 4 piston for racing and Bob & Cincy has gone to oem fronts on all 4 corners which works well. Main reason
is oem rears have about 1.7 vs 4.7 sq inches of piston area.

I did some calculations of various setups and what I ended up with which is the Wilwood 12.19 rear setup but with different calipers with twice the area. ( 4 piston)


This is stock oem setup. Note 54 pound pedal force gives about 1/2 g stock


This is with 4 piston rears with 1.35 rears. Now same pedal force gives 0.8 g. To get same you need MUCH more pedal force with stock


This is bias graph. Neg is front bias. It is so front biased its off the graph for stock brakes


This is with Wilwood 4 piston rears and prop valve slightly. Don't want rear bias at high g stops.


This is the weight transfer graph. Still have more rear weight and need for rear brake at a 0.9 g stop