I'm slapping a boost gauge in my Jackson supercharged NA. Where's the best place to tap into under the hood to get my boost reading?

 

Just before the throttle body is probably the most accurate.

 

Only if you don't want to read vacuum.

Just pick a port, don't make it the same port that your ECU reads off of, assuming you have a MAP based ECU. The ECU matters where it gets the signal from, because some ports have more noise than others, but a boost gauge will be fine on any.

 

why? (He has a JR s/c so he doesn't have an ECU) but again, why?

 

I thought I've heard that the MAP signal is cleaner when it's on it's own circuit, maybe not. If you have multiple ports on the IM, why not just use a dedicated port instead of using a tee?

 

because, why run two vacuum lines into your bay?

tee off the clean FPR line. Tee inside the cabin to the ecu and boost gauge. all the available dedicated ports off the IM are nasty for an ECU.

 

Actually I'm now remembering that's what I did as well.. disregard my original advice!

 

I'm running MS. No ECU.

Anyway, I think I should be good for boost & vacuum reading if I T into the cruise control vacuum line on the back of the IM, right?

 

EBC or things that modulate the vacuum load will cause havoc on the map sig, ask me how I know. But a guage should be fine.

 

My first install, I teed both the ECU and the boost gauge off of the FPR line. The ECU signal was noisy as **** from all the vacuum lines vibrating in the engine bay and the cabin. I kept the ECU feeding from the FPR, and moved the boost gauge feed to one of the nubbies behind the throttle body. No more noisy signal.

 

Tried it off cruise control vacuum line as well as the unused port right behind the TB. I get no reading

 

I tried the cruise control vacuum line & the 1st post on the front right of the IM as it is unused & neither gave me a reading.

 

What boost gauge is it?

 

Glowshift

 

Mechanical or electronic?

 

Mechanical

 

blow or suck on the hose. If it doesn't move, your boost gauge is broken.