Join Date: Feb 2015
Location: Plant City Fl
Thanked 26 Times in 25 Posts
Ok, asked around.
What is the HP rating and does the truck have acceptable performance? I've seen 400 HP B's that only ran 20-22Lbs of boost under a full load and that was normal for them. Also, is he trying to run 1900-2000 rpms? I've seen 425 HP B's that would not boost until they got lugged down to 15-1600 to get some manifold heat going. Don't know if that was right or wrong... but it was 5 identical trucks. And what is the water temp. Some of those were happier powerwise at 195 than they were at 180. Just some thoughts. It may be more operating conditions than an engine issue.
Oh... check the boost gauge for accuracy and the tubing for holes, seen that one too.
That pressure is low should have at least 70 psi, check the filter housing and primer pump. Did he check pressure at filter housing? That is a early C model with a 3ZJ#.