Need help with vacuum line diagram greddy profec b and boost gauge install

[street-racer18]

I just installed a greddy profec 2 spec b and a boost gauge, on my sr20 red top. I've looked at a bunch of write ups and still don't get where all the vacuum lines are supposed to run. Right now I have the boost controller solenoid between the hotpipe and wastegate, bov is ran from top right nipple on TB. A lot of write ups said not to T off the FPR for the boost controller vacuum line. So my question is where should I hook up the vacuum line for the boost controller and the boost gauge? Thanks for your help. If anyone has pics of their setup that would be great!

[Tyler_240]

Your wastegate/boost controller only needs to see boost, not vacuum. Your Boost Gauge can be T'd into your FPR (Top Left), BOV (Top Right) and there should be another connection underneath the Throttle Body that is before the Manifold (Boost Only). I would get your Boost Source there. Or, you can tap your turbo compressor for a fitting, or your hotpipe for a fitting, and get source there.

I have my stock FPR Tee'd into my MAP Sensor and Boost Gauge with ZERO problems. My BOV run to the Top Right, and my boost controller run to the lower nipple on the Throttle Body.

[derass]

Just tee the FPR like the instructions say.

http://www.rx8club.com/attachments/series-i-major-horsepower-upgrades-93/147265d1256162064-need-greddy-profec-b-spec-ii-help-ebc_install.jpg

[street-racer18]

Thanks, I'll give that a try. I have the boost gauge hooked up the the FPR right now, the boost solenoid hooked up to the compressor outlet and the wastegate, and had the bov and boost controller T'd into the top right nipple and it didn't work right. I'll try switching the boost controller to the bottom nipple.

[derass]

Leave the solenoid connected to the compressor, that the right spot. Don't use that bottom port on the TB. Sounds like you have everything connected right. Why do you say "it" didn't work right?

[street-racer18]

It's bogging down under throttle, and boost gauge is only reading vacuum.

[Tyler_240]

Sounds like your wastegate is wide open. If your boost gauge is reading vacuum, then it has to be able to read boost because the TB only does vacuum/boost or boost...

Do you have an internal gated turbo? If you do, I would double check the wastegate pre-load and make sure its adjusted correctly. If you have a fitting on your compressor, then i would get your boost signal from there for the boost controller like you have it.

[Kingtal0n]

the line that goes to the back of the profec B should be DEDICATED, have no T's on it, and should run straight to the throttle body or intake manifold, preferably intake manifold. It is CRITICAL you get this one line correctly routed this way, with no kinks and no T's for the boost controller to work correctly.


#1 cause of people complaining about their profec's performance is that line

[derass]

I do agree that the vacuum line should be free of kinks but it doesn't to be a dedicated. My MAP sensor is tee'd off of the FPR, the EMS uses this as the primary load source as well as the reference signal for electronic boost control.

[street-racer18]

How do I test the wastegate? Now that I think about it, it could be the wastegate. When I bought the car the previous owner put a t28 on it and when I drove it home I noticed it wasn't build pressure well, the turbo bracket was loose and it moved around a lot. I took it off and put a new bracket on it and put it back on. It never ran well after that. I just assumed it was because he never had anything tuned after installing the bigger turbo. That's why I installed the 550 injectors, z32 maf, boost controller and gauge. I had the ecu reflashed by rs enthalpy.

[Tyler_240]

I would remove the wastegate, see if there is a serial # on it and look it up and find out what its rated for. It should be a 6.5~7psi, but it would be best to verify.

Then, you can give it air pressure and ensure it doesn't bleed before that. Afterwards, mount it securely to your turbo. To get the actuator arm correct, adjust the keyway until it just barely goes on the flapper on the turbo fully closed. Then, give it another 3 turns or so tighter. Use a pair of pliers or if you can grab ahold of it, and pull it so that you can secure it to the flapper. This should give you the right amount of pre-load give or take.

[street-racer18]

Thanks, I'll give that a try.