sr vacuum hookup

[Options13]

im trying to get this shit all squared away so bare with me

OK so my current set up is ISIS intake manifold, and i have no idea what kind of throttle body i have heres a pic




ANYWAYS, there are 2 vacuum metal tubes that come off the intake manifold right below the throttle body, and theres 1 metal vacuum tube that comes off the throttle body itself (not visible in picture)..

anyways is the metal vacuum tube that comes off the throttle body at constant pressure? is that where i hook my FPR up too?

i hooked up my FPR to that with a T to my boost gauge, and its reading 0 psi at idle, and when i rev it, it drops around -15 or something like that

the 2 metal vacuum tubes on my intake manifold, 1 runs to bov, and the other runs to actuator

let me know if this is the correct way!


hopefully that all made sense..

[penco]

The one on the actuator should go to your inter cooler piping. And your pics not the best, i only see one vacuum source.

[cotbu]

anything after the throttle body will be constant vacuum, ie. the 2 on the manifold.
The one on the throttle body is before and can be used as a boost source.
hook the fpr up to one of the manifold ports and the other to bov or anything that needs to see vacuum. The internal waste gate does not, need to see constant vacuum.

[Options13]

thanks cotbu! re-routed my vac lines this morning! my car now boosts up to 8psi enstead of 6psi, and also i get a reading from my gauge at idle now, -15 at first then goes down to around -20, that normal?

[dr.klawn]

Originally Posted by Options13

thanks cotbu! re-routed my vac lines this morning! my car now boosts up to 8psi instead of 6psi, and also i get a reading from my gauge at idle now, -15 at first then goes down to around -20, that normal?

yep... it sure is

[Options13]

still getting compression surge only when the car is in the -in/hg, but when i boost up to around 5-7psi it doesn't surge... any way to fix this? i know the vacuum source to my BOV has to be good

[jspaeth]

This has been covered so many times, it is ridiculous.

FPR------> Intake manifold vacuum source
BOV-----> Same
MAP (Pressure sensors)----> Same

Wastegate Actuator-------> Boost ONLY source (somewhere between the compressor outlet and before the throttle body, preferably on the compressor housing or somewhere on the hotpipe).

[cotbu]

Yeah, you're good. To fine tune that bov. at idle adjust it so it barely leaks at vacuum then slowly tighten it till there is no leak at idle, then even smaller turns so you get the response you want. If it's to loose you'll leak at part throttle and cruise, That's why we say recirculate. If you tighten it more so it doesn't leak at pt throttle and cruise, you'll be golden an you'll not stall unless you dump way to much air and IACV is reacting to slow. that's a different issue.