I hope this is the right place to post this. I just got my '68 F250 Highboy back from AutoWorld in Montana where the almost finished installing a 2005 HPCR Cummins and 48RE into it. The truck already had hyrdoboost brakes and because the donor truck had Hydroboost we thought it would all "play nice" together. But I am having trouble with the steering getting very stiff (loosing boost?) when I begin to accelerate out of a corner. I had thought I had a bind in the steering at a certain point, but now I realize it happens when I hit the gas.

My main confusion is since I'm accelerating and raising RPM's, why would the boost drop? It works fine at idle. Could there be something else going on?

Peter

 

Not familiar with that system but maybe there is a leak and when you give it rpms you are losing pressure??? Is the hydroboost setup the original from '68?

 

Is the pwr sterring pump in good shape?? I think that is hat powers the steering, and later on the GMs the brakes also.
Maybe it's not keeping the pump at high enough RPMs at times.