MANUAL BRAKES anyone use them? - Lateral-g Forums

usa-69z · #1 12-18-2012, 12:30 AM

I have no brake power booster on my 69 because of fitment issues (RHD conversion) I am running a wilwood 7/8 master for the brakes on a standard disc/drum setup, 18inch rims and proportioning valve.. I am not happy with the way it feels and not really sure i could lock it up if needed..has anyone got any advice or what my next step should be to improve my brakes? bigger discs and 4 spot calipers maybe ? or ?

**Sieg** · #2 12-18-2012, 01:38 AM

Call Tobin at Kore3. His front GM Big Brake kit with C5 PBR calipers, slotted 13" DBA rotors (if still available) and Hawk HP Plus pads will surprise you. For street use I have plenty of brake and they should handle moderate 20 minute track sessions. I'm running a 7/8" master and can chirp the fronts at 35 mph with a quick stab of the pedal. I would rate the modulation as similar to modern day street superbikes or very good IMO.

www.kore3.com

My 200 tread wear tires exploited the antiquated stock front discs, with this front brake set up I don't have enough tire.

usa-69z · #3 12-18-2012, 03:48 AM

thanx Sieg , i will investigate that option.. Is there a reason you dont run a booster ?

**Sieg** · #4 12-18-2012, 09:50 AM

Quote:

Originally Posted by usa-69z

thanx Sieg , i will investigate that option.. Is there a reason you don't run a booster ?

I like the modulation of a manual system, what you feel is what you get. All of my racing/track experience is on motorcycles which don't run boosters. I also like the old school simplicity of a manual system.

Would I like the system Stielow installed in Mayhem? Absolutely, but it most likely costs more than my car is worth. But then there's Ride Tech's '33 with a manual system that performed nicely this year.

**Steve Chryssos** · #5 12-18-2012, 04:10 PM

I agree. Manual brakes put the MAN back in stopping. The funny part is when you lend your car to friends who are used to power brakes. 'Lent my car to Nick Licata once for an autocross and he got all four wheels off and sent one or two cones to the eighth dimension -- never to be seen again.

usa-69z · #6 12-18-2012, 05:49 PM

so ,im hearing that an upgrade to larger rotors and maybe get some 4 or 6 pot calipers ? would that make a huge difference? mine is really bad right now....

Gav

**Sieg** · #7 12-18-2012, 06:32 PM

My system was a major difference over stock even with the drums it produces respectable stopping performance. Especially noticeable at 80-100 mph when you need to scrub 30-40 mph quick. FWIW - I did the upgrade this year.

I initially wanted 6 piston but couldn't justify the $$ for the application. The C5 calipers appear to offer more bite than tires can hold at lower speeds. If I had a track car I'd probably go 6 piston for fluid and cooling capacity. Don't know if I'd go 14" rotors over the 13" due to un-sprung weight. My 13's weigh 29 lbs. each.

**GregWeld** · #8 12-18-2012, 11:38 PM

Also -- with manual brakes be sure to check your pedal ratio... It needs to be 6 or 7 to 1 to get you the leverage you need for manuals.

usa-69z · #9 12-19-2012, 01:37 AM

Quote:

Originally Posted by GregWeld

Also -- with manual brakes be sure to check your pedal ratio... It needs to be 6 or 7 to 1 to get you the leverage you need for manuals.

how do you work out the ratio for the pedal? is there a way to do this?

**GregWeld** · #10 12-19-2012, 11:20 AM

Measure your pivot point to the center of your brake pad (i.e., the length of the pedal)... and then from that pivot point to the Master cylinder push rod point.

Divide the longest length -- by the shorter length and that's your rod ratio. It needs to be 6 or 7 ---- if it's 4 that's a power brake ratio.

The brake pedal is a LEVER -- you need less leverage for power brakes than you do for manual brakes...

You want to be able to push 100 pounds with your leg and have that translate into 600 or 700 pounds of effort on the master cylinder.