Holy moses, brakes are almost too effective!

Well my friend and I finished the YJ brake upgrade this afternoon... Holy crap it locks up all 4 tires with a pinky fingers worth of pressure!

I love the performance, but it has brought up two things which I might consider a problem:

1) The brakes almost seem too powerful.... Is it possible that the vacuum source for the booster is too good? Is there any way to adjust the intensity of the brakes related to the vacuum?

2) The old master cylinder had two wires come off the bottom, which I believe triggered the brake lights. Now no brake lights come on at all with the new master cylinder/booster combo. Any ideas on how to put in a switch to restore that functionality?

 

I couldn't tell you, the YJ booster/master cylinder came from a YJ which had been completely parted out. This was the the last part in the Jeep at the pick-n-pull. It was just sitting in the tub. I would say there must be some type of switch that is triggered as the brake pedal is released all the way up. I would say that the brake lights were independent of the master cylinder in the YJ, whereas the CJ had the two electrical wires coming from the bottom of the old master cylinder.

 

Thanks for the picture, I think i will have to rig up something like that tomorrow if possible. I know its not very safe to drive around with inoperable brake lights.

 

Anyone have any more thoughts on problem 1)?

 

What brake cylinders are you using? Stock drums or did you convert to discs? If your brakes are stock with the exception of the master cylinder you may just not have an ideal master-wheel cylinder hydraulic ratio. No problem really unless you put one of your passengers through the windshield.

The amount of vacuum won't change for different locations. Manifold vacuum will allways be manifold vacuum wearever you tap into the manifold, unless of course its "ported" vacuum.

Kevo

 

I have drums all around... Will a disc brake conversion for the front give me more appropriate stopping power?

 

Gotta jump in, I have the same configuration on my 73 CJ5. Drums all around with a 96 YJ power master cylinder, no proportional valve as they are all drums. I completely rebuild the lines with SS from Classic Tube and new brake hardware with the drums resurfaced. I agree they work VERY well now, but, I do plan to replace my 30's with 33's and this will drag them down to a more balanced braking. As for the switch, I ordered switch from Watson Streetworks http://www.watsons-streetworks.com/brake_switches.html and it works great. Plan to do the drilled drums some day when I finish the other 100 projects.

NHD

 

Hey thanks for the link ndavis2, and welcome to the board! Good to hear someone else had a setup like mine.

 

I used a Toyota pickup brake light switch, a L bracket and a hose clamp. I clamped the switch using the L bracket to the steering column and adjusted it so that it is turned off by the brake pedal. works great. I dont have any pics as its almost impossible to get a good camera angle on it.

 

I used the booster/MC from an 86 E350 (non-deisel) and with 35 inch tires, they are still too strong. At least it stops, though... it didn't before.

A friend of mine made up a bracket like the one in the picture above. We got a switch from NAPA for a 78 chevelle sedan. Works.