Mopar Hydroboost problem

[Cudajas]

Hey folks!

I am working on a hydroboost instal on my 74 cuda.

I am using a HB unit from a fullsize chev van, sourced from the wrecking yard.

Running -6 PTFE hoses with rubber return lines.



I have drilled out the return fitting on the HB unit and added a separate -6 return fitting on the PS pump!

PS pump is a rebuilt factory Saginaw unit.

THe MC is a mopar aluminum unit of unknown bore size.

I ran all new brake lines and added a line lock. All pressure bleed and no air in the lines.

I tried to bleed the HB system several times.

NOW the problem, the brakes do not seem to work very well. I have only tried it on jack stands at this point. Drop it in gear and the pedal is pretty spongey and the rear wheels do not stop spinning.

The other issue is the pedal does not return. I have to lift it up with my foot to turn off the brake lights.

At this point I am not sure what the issue is.

I thought of going to a new MC, Wilwood suggested a 1 1/8th bore, but will that help the pedal return.

Any thoughts before I throw kore money at it would be appreciated.

thanks,

jason