Author Topic: Brakes  (Read 6659 times)

Offline BK

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Brakes
« on: April 03, 2014, 04:32:01 PM »
I have an Altered project and I'm just about ready to finish the brakes. It's a 4link 125" wheel base with funny car style wheels and tires up front. It has 4 wheel brakes but there isn't any lines yet. Trying to decide whether to hook all 4 to the foot pedal or hook rears to pedal and fronts to hand brake. I'm leaning towards first choice. Would like to here some pros and cons either way. I'll address master cylinder proportioning valve after I decide for sure what I'm doing.   

dreracecar

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Re: Brakes
« Reply #1 on: April 03, 2014, 04:39:23 PM »
strange  (chrysler) dual master around $100
add porportioning valve to the fronts

Offline BK

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Re: Brakes
« Reply #2 on: April 03, 2014, 04:40:58 PM »
So far that's what I was thinking.

dreracecar

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Re: Brakes
« Reply #3 on: April 03, 2014, 04:44:05 PM »
front port to the rears and rear port to the front

Offline Curly1

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Re: Brakes
« Reply #4 on: April 03, 2014, 07:51:37 PM »
Mine has front and rear brakes to one master cylinder. I have a completely separate system on a hand brake with additional calipers on rear only. The foot brake has the harder compound and the hand brake has softer compound. I did not like not having back up system just in case. Many of the tracks around here are shorter than I like and want to be able to stop. I know too many people who have had brake failures and it can get ugly quick with out a back up system.

Offline BK

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Re: Brakes
« Reply #5 on: April 08, 2014, 06:30:00 AM »
Here's the plan. Chime in if you see a problem. To start out my pedal ratio is 3.3-1 so I need to keep the bores on the smaller side. My target is for the front brakes to have 70% of the pressure of the rears. I'm thinking if I use a 7/8" cylinder for the front and a 3/4" for the rear my balance should be pretty close. With 150# of push on the pedal the rear's should have right around 1,200 PSI the fronts should be around 840 PSI. They both will have remote reservoirs which should eliminate the need for a residual valve. I have a brand new 7/8" cylinder so I only need to purchase one cylinder. If I need to adjust the balance further. Is there any advantage balance bar vs balance valve?

dreracecar

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Re: Brakes
« Reply #6 on: April 08, 2014, 08:43:16 AM »
Most people do not go into that depth when designing their brake system. Simplicity is paramount towards function.  2 master cyl weather the same or different will require the use of a balence bar because you will never get them to travel equal otherwise and produce the required pressure needed. The simplicity of the tandam (engineered for fr & rr brakeing systems) with just 1 push rod to the lever handle and with a porp valve is why most F/C use it. If the point is to also have a stageing peddle along with and hand brake, install the peddle and run a push/pull cable over to the brake handle.

Offline BK

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Re: Brakes
« Reply #7 on: April 08, 2014, 10:00:23 AM »
No staging brake. It will be pedal only. I wasn't finding a tandem MC small enough to get the pressure and price where I wanted it.