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SSBC brakes hard pedal hard to stop?

Posted By: sixpacksteve

SSBC brakes hard pedal hard to stop? - 10/03/16 12:43 AM

brake pedal is right at the top hard as rock, seems i really have to stand on pedal to stop car. is this normal or can i adjust something?
ssbc calipers.rear drums
Posted By: ahy

Re: SSBC brakes hard pedal hard to stop? - 10/03/16 01:20 AM

No... you should not have to stand on it to stop.

A few questions about the setup. Power or manual brakes? Original type or new master and what diameter?

In general some aftermarket calipers like the Cobra spec units I run and (I think) the SSBC pieces have smaller piston area vs OE. They need more line pressure for good stopping from either a smaller bore master or stronger booster or both. Weak vacuum to the booster or booster problems could cause this problem as well.
Posted By: sixpacksteve

Re: SSBC brakes hard pedal hard to stop? - 10/03/16 02:48 AM

manual brakes,new master not sure on diameter. is there any adjusting the porportion valve?
Posted By: ahy

Re: SSBC brakes hard pedal hard to stop? - 10/03/16 03:16 AM

There is no adjustment on the factory prop valve... and front discs should typically get full pressure through a simple "T". The rear drums need the adjustable prop valve typically to balance F/R braking.

Manual discs are challenging... if the piston area in your front calipers is smaller than OE, which I guess it is with the SSBC setup, getting manual to work well is really hard. A smaller bore master, eg 15/16" may help though you need to know what you are starting with.

Was your car manual brakes to start with? The reason it matters is he pedal setup gives more leverage with manual brake setup.
Posted By: 70Cuda383

Re: SSBC brakes hard pedal hard to stop? - 10/03/16 05:31 AM

try a smaller diameter master cylinder.
Posted By: Sxrxrnr

Re: SSBC brakes hard pedal hard to stop? - 10/04/16 11:19 AM

15/16th mc resolved my front disc, rear drum, manual brakes on E Body. Had same issue as you describe when running 1 1/8th mc. Found Dorman 4 bolt mc 15/16 on Amazon for less than 50 bucks that did the job. Also able to switch from really filthy dirty pads which were soft and did help braking some with 1 1/8 to very clean ceramic pads after switch to 15/16th pads.

Here is photo of 15/16th mc on E Body.

Attached picture IMG_1350.JPG
Posted By: sixpacksteve

Re: SSBC brakes hard pedal hard to stop? - 10/05/16 02:53 AM

i don;t know size of mc but how does that affect stopping? i have single piston stock calipers on my race dart that runs 10.0's and stops great.
now these are after market suppose to be better brakes, and they feel like old shoes that when they get hot there Not stopping. when cold
Posted By: ahy

Re: SSBC brakes hard pedal hard to stop? - 10/05/16 03:30 AM

A smaller diameter master provides more brake line pressure = better stopping power.
Posted By: moparx

Re: SSBC brakes hard pedal hard to stop? - 10/05/16 01:22 PM

Originally Posted By sixpacksteve
i don;t know size of mc but how does that affect stopping? i have single piston stock calipers on my race dart that runs 10.0's and stops great.
now these are after market suppose to be better brakes, and they feel like old shoes that when they get hot there Not stopping. when cold
i'm not trying to sound patronizing, but have you read feets brake math sticky at the top ? lots of good info there that can help you get familiar with how brake systems work and things to do to help you accomplish what you want. highly recommended.
beer
Posted By: sixpacksteve

Re: SSBC brakes hard pedal hard to stop? - 10/05/16 10:19 PM

i got the process. been doing brakes long time. Not with these after market performance brakes. simple, you apply pressure to the brake caliper it squeezes the rotor and it stops! i've heard from more than a few guys they have same problem. Wilwood etc.. NOT yet fixed. SO why the super hard high pedal and car doesn't slow down? Sorry for rant!
Posted By: Supercuda

Re: SSBC brakes hard pedal hard to stop? - 10/06/16 12:30 AM

Last place I would by a disc brake kit from is SSBC. I would either replicate a stock setup with stock parts or go with Dr Diff, AR engineering or similar for bigger than stock brakes.

Too many issues, however if you google SSBC issues there is a thread on Dodge Charger.com that might help.

http://www.dodgecharger.com/forum/index.php?topic=95452.0
Posted By: Kern Dog

Re: SSBC brakes hard pedal hard to stop? - 10/06/16 07:05 AM

Originally Posted By sixpacksteve
i got the process. been doing brakes long time. Not with these after market performance brakes. simple, you apply pressure to the brake caliper it squeezes the rotor and it stops! i've heard from more than a few guys they have same problem. Wilwood etc.. NOT yet fixed. SO why the super hard high pedal and car doesn't slow down? Sorry for rant!


Great point and your "rant" is surely appropriate. Who the hell swaps in disc brakes so that the car stops worse? What person would do this on purpose?

I can see and have personally endured situations where a conversion has been assembled using a bunch of unrelated, non stock parts. Sometimes it all works, sometimes it sucks. The "advantage" of installing a packaged kit from a reputable source is that it comes with the expectation of safe and proper performance. The buyer assumes that the parts are engineered to be a better setup as compared to the stock drum brakes.
I'd be pissed if I spent $$$ and the brakes still sucked.

Years back, I was running a 292/509 cam in my 440/493 70 Charger. The low vacuum made my low speed braking what could be best described as "LESS than optimal". I thought it would be a good idea to switch to a manual brake master cylinder. HERE is where things went awry...
My whole setup was pieced together from various sources. I had the mid 70s style 12" front rotors, the 2.6" single piston front calipers but then a 10.7" rear rotor with a 1.5" rear caliper. I had a few manual brake master cylinders here of different bore sizes. There is no shortage of info online regarding what effect the bore size has on pedal feel but I decided to try things for myself. I tried the biggest bore first, I think it was 1 and 3/16".
It was horrible. It felt like the brake pedal travelled hardly an inch and the car felt like skidding tires on wet ice.
I tried an 1 1/32" and it felt about the same. The 3rd one was an iron 15/16"unit. It felt okay so I thought I was getting close. I called Dr Diff and he suggested an aluminum 15/16" MC he had in stock. I installed it to find it felt about the same as the iron one of the same size.
I started reading here and elsewhere about bore sizes, pedal ratios and such, all in the hope of making a NON power system work for me. I was on a deadline though. I needed he car to be back together for The Spring Fling in Southern CA. I ended up wussing out...I put the power booster and 15/16" setup back on along with a small vacuum can.

Some time later, I took a spare brake pedal and drilled the pushrod hole 5/8" higher then welded washers around the hole. This affected the pedal ratio, reducing the pedal effort. Days later, I saw that I had a DISC/DRUM proportioning valve in the car! What ??? All along, I should have been using a drum/drum distribution block.
4 wheel drum AND 4 wheel disc systems traditionally rely on the wheel cylinder or caliper bore sizes to determine the proportioning. The power booster was masking some of the incorrect proportioning so without it, there was simply not enough force.

All of the mish-mash and mistakes I've made have at least helped me learn. I suspect that if I tried swapping in the manual MC now, I'd have better luck with it!
Posted By: Kern Dog

Re: SSBC brakes hard pedal hard to stop? - 10/06/16 07:15 AM

Another thing:
I have seen a certain style of master cylinder sold with SSBC kits that some call the "Corvette MC". It is sorta oval in shape and uses a big bore. I think it was at least 1 1/16". As strange as it sounds, a fraction as small as 1/16" can have a dramatic effect on braking feel and performance.

For many years, I ran a 12" front disc, 10" rear drum system with that 75 Dart power booster and 15/16" MC. The car stopped fantastic. I only went to the rear discs because disc brakes look better than the small diameter drums through the wheel spokes. Yeah...call me superficial.
Posted By: moparx

Re: SSBC brakes hard pedal hard to stop? - 10/07/16 01:59 PM

i didn't mean to question your ability or experience. when you asked the question what the master cylinder bore had to do with the way your car stopped, i thought you may have missed feets sticky which explains things pretty good. i understand frustration from projects as i have been playing with vehicles starting with helping my grandfather in 1959 as a young buck. you are correct about complaints from some of these kits not living up to their claims. when you get to the bottom of your problem and the solution that helped you, please let us know the results.
beer
Posted By: Sweet5ltr

Re: SSBC brakes hard pedal hard to stop? - 10/08/16 06:33 PM

Please contact DR. DIFF and let him set you up with one of his master cylinders. I went from a super stiff, ridiculously hard pedal (with a factory bore size); to a firm, smooth pedal with his 15/16" unit. I'm running his Stage 4 'Brembo' kit on the front and Baer's on the rear.
Posted By: John_Kunkel

Re: SSBC brakes hard pedal hard to stop? - 10/08/16 10:06 PM


I don't see the MC size as causing a high/hard pedal. I'd be looking at the pushrod length possibly not letting the rear piston in the MC fully return.
Posted By: Kern Dog

Re: SSBC brakes hard pedal hard to stop? - 10/08/16 11:33 PM

Originally Posted By Sweet5ltr
Please contact DR. DIFF and let him set you up with one of his master cylinders. I went from a super stiff, ridiculously hard pedal (with a factory bore size); to a firm, smooth pedal with his 15/16" unit. I'm running his Stage 4 'Brembo' kit on the front and Baer's on the rear.


While I agree that the man knows his stuff and sells quality parts, he cannot make up for a mismatched combination. (IF there is one) The 15/16" MC he sold me made no difference because I had a disc/drum proportioning valve despise running a 4 wheel disc setup. I forgot to change it when adding the rear discs and I didn't think to tell DrDiff when I called him.
Posted By: AndyF

Re: SSBC brakes hard pedal hard to stop? - 11/01/16 10:23 PM

Last time I looked at the SSBC kit they were using a Mustang 4 piston caliper with small piston calipers. The pistons were too small and didn't generate much brake force.

I learned the hard way back when I was doing brake kits that hardly anyone understands how brakes actually work. Most people know that if you use a big cam with a tiny carb you have mis-matched parts and the engine doesn't run right. But I found that almost nobody understood that if you put tiny calipers and a big master cylinder together you couldn't stop the car. For some reason people think they can mix and match brake parts and it will work.

The brake system has to be properly balanced. Pedal ratio, MC bore size and caliper piston size all have to work together or else you have a mess. A lot of the disc brake kits available for classic Mopars do not work because of this problem.
Posted By: Kern Dog

Re: SSBC brakes hard pedal hard to stop? - 11/02/16 06:34 AM

Andy, you are SO right! I have been guilty of making cheap ass decisions with brake systems and been very frustrated with poor results.
Currently I have a power booster setup that works great. Naturally I want to mess with the success and try a manual setup again... hammer

This is for a few reasons: I want to clean up the engine bay. I want to reduce weight and the complexity of the system. I am considering a return to a more radical cam that needs either a manual setup or a vacuum pump that adds even MORE weight and complexity.
Finally, I have a buddy with an XV Motorsports X brace that ties the fender aprons to the cowl. It does not clear with this booster in there.
Posted By: Hemidavey

Re: SSBC brakes hard pedal hard to stop? - 12/07/16 12:15 AM

Ran into same problem with manual SSBC front brakes before. A customer came in who had installed a set, it took both feet to stop this car! We tried various parts, different sized masters, new brake lines and hoses, disassembled prop valve, cleaned, retested still didn't work, tried everything we could find or test. Went through all Feets stuff too. Bought brake pressure test gauges, all good, Ssbc told us there was nothing wrong with their parts. Customer finally gave up, put Baer parts on, car stops like a vette.
Posted By: moparx

Re: SSBC brakes hard pedal hard to stop? - 12/07/16 04:25 PM

what were the differences between the calipers in each system ?
beer
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