boost and vacuum manifolds

[Johnathansgalant]

A while back i broke a j pipe nipple for the wastegate as it was apparently too close to the manifold so it bent.. Ne ways i moved the wastegate line to a t into the intake manifold and the boost rised 2 psi to 12 or so..... eventually i went with bigger exhuast and a vacuum manifold for bov and what have you. My boost increased to 14 to 16psi.. I finally got the chance to drill my j pipe and install a barb for the wastegate. I upgraded to a big 16g and the boost was going to 18psi before - now its sold 8or 9psi... Just a word of advice for others who are beginning the turbo journey -- ur best wastegate tap source is on the jpipe or immediately on the hotpipes.... Everyone probably knows this but i put it off figuring it wasnt my problem because my boost gauge works on the manifold but it was the exact issue... Remember we get some pressure drop not to mention the length of travel to fill the intake manifold and brake booster line so by that time the turbo spooled up to a higher psi and is already flowing too much exhaust to be stopped by a late opening wastegate... . maybe someone will be helped by reading this... i only mention it because so many people use intake manifold signals for the wastegate.

[run1206]

thanks for the heads up johnathan. not sure which way my j-pipe will be pointing to, but i'll make sure to watch for those added pressures after the install.

[bmore303]

The worst place is a line from the manifold. Best is either the hotside or J-pipe. Next best would be early in the lower intercooler piping.