Am I expecting too much?

[RSX302]

Had a hunch you would look at power assist. I wasn't fond of the massive leg pressure either.

OK.... think I found part of the problem.............

me.

Adjusted up the rear drums tighter..... switched back the Rayobestos pads ( didnt like the dust from the Hawks). Sanded the rotors and pads.... bed them in last night....

took car out today........ nice pedal....

and this time did a few panic stops.......... and really stood on the pedal. She stops pretty damn good, rears will now lock , fronts not yet, but it is close.

I think from driving cars all week with power brakes........... I am just not used to how much pressure it takes to lock up a manual brake car.....
I know it sounds stupid, but I think that is my issue.....

Has anyone else ever felt this issue? going from power brake cars 99% of the time to your manual brake "fun" ride.......

I've dealt with the "not being able to lock up" issue a few years back. Ultimately found that manual brakes do not work well on heavy street cars (>3500lbs) unless you do one or more of the following:
Disclaimer; I also have big sticky Toyo’s on a 3800lb car. Lighter car, set-up and smaller less sticky tires will lock-up sooner.

Yes pad Cf is a huge factor but...if the extra pad Cf doen't do it for ya here is more info. Ceramic pads are only for show because of no dusting. Not too good at stopping.

*Higher Caliper pressure (1000psi min..1500+ ideal based on 4sq in caliper) required for pad Cf below .4 (street pads)
I used Willwood’s BP30's (.5-.6Cf) on 13" rotors, SL6's and 3/4 master. That locked them up! Stopped the car perfect, (to my liking) but at the expense of major dusting, squealing and rotor degradation. Needless to say I removed them. Oh yea. pad knockback started on the rear rotors with the Ford 9” due to the small master. Now I'm using power assist with large 1 3/16 master and Wilwood BP10’s. (.4Cf) Will put you through the glass..and lock up if I so choose.

*Increase Pedal Ratio Currently running 4:1 power assist and have run up to 6:1 and 8:1 for the previous manual system to try and get more caliper pressure.

*Larger Diameter Rotors (i.e. 13 to 14" nets approx +10% rotor braking torque)

*Power brake assist Just a hunch, but if you don’t like the higher pad Cf’s to get your desired braking, you’ll be switching over.

Good Web Calc:
http://www.jakelatham.com/radical/in...culators.shtml

[Vegas69]

Manual brakes take some getting used too. It sounds really stupid(Ron) but it's hard to convince yourself to stomp on the pedal when most factory cars require your pinky toe. Manual brakes are a beautiful thing for threshold braking and high speed and road racing. I've grown to like them a lot more. You just can't use them like a daily driver. You really need to put your leg into them. It doesn't feel natural.

[67gtonut]

Yeah...... still going back and forth on this now.....

Drove it for a little bit last night.......... by the way, the UMI stuff makes this thing HANDLE!!! ..... I am trying to get past the mental block about the pressure needed to woah this car down.... I love the clean look under the hood of the manual brakes......

Might stick this out for now......... It has a great pedal, but just need to recalibrate my head on pedal pressure.....

[gsxrken]

Your post sounds familiar. I went from original power brakes to wilwoods all around and couldn't lock them up. Juggled masters, pads, vacuum reservoir, then went manual side by side CNC master cylinders with balance bar, never was happy with the effort or cold bite of the brakes. Did a gauge test and I wasn't getting more than 900psi without serious bend the seat effort. My daily drivers spoiled me too.
Finally bit the hydratech booster bullet... $$$ but I'm not posting about my brakes anymore. ;)

[67gtonut]

Man, I am glad I am not alone in what I was/am feeling.....

How hard is a Hydroboost install? Can it be made to look neat?

I will do some searches on here.....

[RSX302]

Manual brakes take some getting used too. It sounds really stupid(Ron) but it's hard to convince yourself to stomp on the pedal when most factory cars require your pinky toe. Manual brakes are a beautiful thing for threshold braking and high speed and road racing. I've grown to like them a lot more. You just can't use them like a daily driver. You really need to put your leg into them. It doesn't feel natural.

I agree..I love manual brakes for racing. I was trying so hard to make my manual system work, but when I was pushing so hard that I seriously thought I was going to break the pedal linkage or something (bending the steering wheel for leverage) I still couldn't get the car to slow let alone lock them up. This is when I started with pedal ratios, smaller MC's and more aggressive pad compounds to do the job. NASCAR style. Although the final result worked very well and to my stopping power liking,(medium-hard pedal pressure to lock) I wasn't going to live with the fact that it was chewing up the rotors, dusting horribly and squealing. I had to throw in the towel.

I drove my buddies GT3 Porsche and I was like, DAMN! this thing stops incredible.. Great pedal feel (easy-medium pedal pressure)and will launch you through the window. Imagine that--power assist with huge brakes. This is when I started looking at power assist. Yes, Porsche GT3's have aggressive pads too. Dusting and squealing.

Since most of our vehicles see 90%+ street use, we need to be comfortable with our brakes on the street. If I build a car for 90% track, it would most definitely have manual along with being 1000lbs lighter.

I have to say I'm very happy with the performance of the ABS Electric Power brake system (no plug intended) it has a very nice pedal feel both on street and on the track. Solid medium-hard press pedal--not touchy at all. Feels like manual brakes with great stopping power with Wilwood's SL6's and BP10's (.45cf pads & 4:1 PR)

[RSX302]

Man, I am glad I am not alone in what I was/am feeling.....

How hard is a Hydroboost install? Can it be made to look neat?

I will do some searches on here.....

You are not alone..You need to set the car up to what you are most happy with. Everyone has there own taste in brake feel.

[67gtonut]

OK..... digging up my own thread to get some last opinions....

Dont want to do Hydroboost.....

Looks like the best way for me to get a nice modern style pedal from what I am reading is :

1 1/8" Master and at least a 8" Dual Diaphram Booster.....

Any easy bolt in matched set-ups that they would recommend ?

Thanks

Troy

[Skip Fix]

Might look at a 79-81 TA factory 4WD setup, although could be a 9" dual. 81 has a quick take up aluminum master.Matched from the factory but they did use less pedal ratio than the disc/drums with the large single booster.

[67gtonut]

Just updating my old thread to finalize.....

Went with a 9" single booster and a 1 1/8" Master.....

Love it..... Took my time with the lines to make it look nice.....