My truck is still overboosting and im stumped.I Had it at eps for the second time and left with the red *** for the 2nd time... Set up is in sig. I have a kbracing kit with a pt 76mm .81 ar,40mm jgs wastegate 10lb spring and never even checks up Geoff let off around 14-15 psi after the 3 pull I took it the house... final #'s 380hp 434tq 8.5 timing running out of fuel and no meth.. Anybody got any idea's before I burn it?

 

Which port are you referencing on the wastegate? Should be the bottom one with the top one open to atmosphere

 

Thats correct

 

A leaky diaphragm? Where is your boost gauge port mounted in correlation to your wastegate pressure port?

 

Do the kb kits have the waist gate going back into the down pipe or in open air? I had the same problem with mine, I got mine in open air and couldnt get it under 13psi with a 46mm wg, I had a 3.5 in down pipe with a small straight throw muffler so it flowed real well, I ended up putting my stock cat back on cause it was so loud and just have cutout now for racing, anyways now I can keep it rock solid at 8 psi, maybe even lower if I put in a lighter spring. So a little back pressure helps alot to keep the boost down.

 

Well my first go around my wg diaphragm was jacked up I sent it back to jgs they put a new diaphragm in it. Before when it was jacked up my boost gauge was reading -5 to -7 now that its fixed its -17 to -20.

 

The boost gauge is referenced off my vac block where everything is tied into.

 

Wg is going back into the dp pipe witch is 3.5" into a 4" exhaust straight thru diesel muffler.

 

Are you using the bigger (softer) outer spring or the smaller (stiffer) inner spring? Tried applying compressed air to the fitting to see if its holding air and moves smoothly?

 

Whatever the 10 lb spring is supposed to be.. Im gonna take it out and see if the 7lb spring will help out any and go from there...