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Installing Hydroboost and bigger brakes in a 1970 Charger

I’m a fan of hybroboost systems. I ended converting over to a Wilwood master with there proportioning valve. Bent all new lines and plumbed all the high pressure and low pressure lines myself. I used bigger caliper brackets to run 14inch rotors front and rear. One of the better upgrades I have done. Excuse the wiring. This was before the American auto wire harness.

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ImScrewedd said:
I’m a fan of hybroboost systems. I ended converting over to a Wilwood master with there proportioning valve. Bent all new lines and plumbed all the high pressure and low pressure lines myself. I used bigger caliper brackets to run 14inch rotors front and rear. One of the better upgrades I have done. Excuse the wiring. This was before the American auto wire harness.

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Click to expand...
Where did you find rotors that size that fit? What are the specifics of all that?
 
I remember that. He is a unique guy....He surely patched together some custom stuff to make it all fit and work.
I have 18" wheels. A 14 inch rotor would fit.
 
Kern Dog said:
I remember that. He is a unique guy....He surely patched together some custom stuff to make it all fit and work.
I have 18" wheels. A 14 inch rotor would fit.
Click to expand...
Well I just looked... 14" AMG rotors are about $400 each... Kevin is a Mercedes Parts manager, he got his for a deal... I think I remember a zone rep basically giving them to him...
 
I guess with something like that, the center bore would probably have to be machined out to the Mopar 2.81 number and the wheel pattern would need to be redrilled. A Radial caliper mount would be the easiest to fabricate.
 
Looking forward to hearing your thoughts on how the setup works, been tossing the idea around myself lately.
 
Kern Dog said:
Where did you find rotors that size that fit? What are the specifics of all that?
Click to expand...
Brake rotors are for a GT500, so are the calipers. I chose powerslot. The center bore of the rotor had to be enlarged a little. 5-10 mins per rotor with a drill and a drum sander. fit perfect
 
****UPDATE****

I have abandoned the Hydroboost system for the car.
After spending numerous hours trying to get it to work, I never was able to do so. In all the efforts, I never got the unit to produce any assist at all. The lines were clear, no kinks. The lines were connected to the correct ports. I wore out 2 steering pumps in the process. First off, I started the fresh engine and had no boost and a rear main leak. I fixed the leak and restarted the car. The steering was working so I assumed the brakes were boosted too. The wife helped me bleed the brakes but didn't tell me how the pedal felt. When I went to drive it, It was stiff as you'd find a power brake car with the engine off. Then the steering assist started to fail. I swapped in another pump and the same thing happened again. Good steering assist but No brake boost....then the steering failed again. I tried several bleed procedures with the thought that maybe it just had air in the lines. I drove around the backyard and it never improved. I don't know much about these systems but it seemed strange that the steering would work for awhile but the booster never did since the fluid goes through the booster before the steering box.
I suspect that the flow control valve for the HB is somehow stuck and not moving to allow flow and boost.
Regardless, this annoyed me enough to call it quits and remove it.
I will be installing the same 15/16" manual master cylinder that I put in before I was given this HB unit to test.
I wanted to close this thread out with the recent news in case anyone stumbles upon this and wonders what happened.
Thanks to all that offered help.
 
Years ago when I used this same rowdy cam, I had vacuum-power brakes. I installed a vacuum pump to augment the setup and it worked quite well.
I may revisit that idea if the 15/16" manual setup isn't adequate.
 
Kern Dog said:
****UPDATE****

I have abandoned the Hydroboost system for the car.
After spending numerous hours trying to get it to work, I never was able to do so. In all the efforts, I never got the unit to produce any assist at all. The lines were clear, no kinks. The lines were connected to the correct ports. I wore out 2 steering pumps in the process. First off, I started the fresh engine and had no boost and a rear main leak. I fixed the leak and restarted the car. The steering was working so I assumed the brakes were boosted too. The wife helped me bleed the brakes but didn't tell me how the pedal felt. When I went to drive it, It was stiff as you'd find a power brake car with the engine off. Then the steering assist started to fail. I swapped in another pump and the same thing happened again. Good steering assist but No brake boost....then the steering failed again. I tried several bleed procedures with the thought that maybe it just had air in the lines. I drove around the backyard and it never improved. I don't know much about these systems but it seemed strange that the steering would work for awhile but the booster never did since the fluid goes through the booster before the steering box.
I suspect that the flow control valve for the HB is somehow stuck and not moving to allow flow and boost.
Regardless, this annoyed me enough to call it quits and remove it.
I will be installing the same 15/16" manual master cylinder that I put in before I was given this HB unit to test.
I wanted to close this thread out with the recent news in case anyone stumbles upon this and wonders what happened.
Thanks to all that offered help.
Click to expand...
I need the part number on the 15/16" MC please for the Cuda.

Thanks
 
The 15/16" unit is from Dr Diff. I don't recall the part number.
 
After all the frustration and effort, Dr Diff sent me this.....
***********************************************************************************************************
  1. Jack the vehicles up so the tires are just clear of the ground.
  2. Make sure the steering wheel is centered and start the engine.
  3. SLOWLY turn the steering wheel to the right half an inch from center and then left half an inch from center. Continue to do this SLOWLY increasing the amount you turn the wheel half an inch at a time until you are going lock to lock. This process should take at least a half hour.
  4. During this process, it is important that the fluid level in the pump remain above the pump casting so you do not introduce more air in the system.
  5. If you get small bubbles appearing in the fluid, you have to shut the vehicle off and walk away until the bubbles are all gone. If small bubbles re-appear, you need to shut the engine off again and take another break. There is no way to speed this process.
  6. Once you have gone through this process the steering and brakes should work.
**************************************************************************************************************

This is not the procedure that I read in the numerous articles and online forums. Even so, I doubt that it would have made a difference and I doubt the legitimacy of it.
For this to actually be true, EVERY new vehicle equipped with a hydroboost would require this procedure. Can you imagine a United Auto Worker spending over a half hour at union scale doing this on every production vehicle?

For the final effort, I did a similar procedure. Prior to this I turned the wheel and pressed the brakes as mentioned in some online articles.
I had the car in the air. I turned the wheel lock to lock relatively slowly 3 times, then shut the car off and manually pushed the wheels lock to lock.
As stated, this made zero difference and it was burning up the pumps to where the steering was going out.
Enough is enough. I'm done with it.
 
Many times the old system is a much better proven system. It’s not worth the headache. I agree with you Greg, move on, have fun and drive it like you stole it.
 
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