Hydroboost conversion on First gen engine

[MAXX IT OUT]

I have been working on a cummins swap into a 67 chevy C30, a non intercooler VE engine with a NV4500 tran, AAM 11.5 rear axle, and 80 C30 front disk brake conversion. I originally was using a 90 hydroboost unit with the original dodge power steering pump and was having issues with the pedal sticking down and locking up the brakes. I figured that it's was because it sat on pallet for a few years after I pulled it off original vehicle before I used it here. So I upgraded to new lml duramax hydro unit and lbz master like I have on my 01 LB7. Problem isn't as bad now but it still drags after stepping on the pedal. I know the newer pumps have duel return lines, one from the steering and one from the hydro, but people claim that it should not be a issue to have them teed together. It didn't make a difference when I split them on the old hydro unit, so I don't know if there could be a issue with the factory power steering pump, ie difference pressure or GPM. Any insite would be appreciated

 

[MAXX IT OUT]

Added a second return to the power steering pump, still acting the same.

 

[MAXX IT OUT]

Got it sorted out finally, if anyone has this issue in the future your brake pedal itself needs to be very free moving to the point of being sloppy, mine factory pedels are a very tight fit and was causing a bit of pressure to be still applied to the pedal, draging the brakes.

 

[biggy238]

Thanks for following up. Many threads over the years have gone unresolved

 

[Red Sleeper]

So if you drive an old jalopy truck, the pedals need to be sloppy. Got it.