iceburgslim

Hey all, I need assistance in figuring out what is causing my boost problems....the car is a 97 Civic EX with the greddy SOHC turbo kit, Type-S BOV and the realy small Greddy intercooler. Stock clutch, exhaust and fuel........I am using the blue box for fuel managment. I am running the stock boost, and the wastegate vacuum hose is run off of the nipple on the turbo compressor side. Now onto the problem.....after installing the intercooler today, the car runs great and will boost about 5psi, but as soon as the RPM's reach about 5500 rpm the pressure drops to about 2.5psi. It is pretty consistent with engine speed, and doesnt matter which gear I am in. Also, now at idle there is air being released by the BOV, it makes a very deep (annoying) noise. I can feel the air rushing out when I put my hand over it, and if any throttle is applied the noise goes away. If I pinch off vacuum to the BOV the noise also goes away. I have the vacuum line for the BOV t'd off of the line for the fuel pressure regulator. I think the boost drop could be caused be a slipping clutch, but it doesnt realy feel like it's slipping when it happens, and the loss is too consistent. I am at a loss and would appreciate any helpful input. Sorry about the long post! Thanks !

turboD16

take the vacuum line off the actuator and tap it to a manifold source...and use the port on the turbo and hook it up to the bottom port on your BOV..it will hold boost to redline after.

turboD16

for the idle air through the BOV..just adjust the nut on the BOV to where there is no air coming out at idle.

iceburgslim

Thanks, I will give it a try. I adjusted the BOV before, but the spring was too tight and the BOV would not open, causing compressor surge. I'll let you know how it goes. Thanks.

falcongsr

yup. thats pressure loss for ya. the intercooler might be hurting (flow) more than helping at some point (probly near redline) cause the temps are gonna get hotter just to push air thru that restrictive IC.

iceburgslim

Okay, well I ran the wastegate signal off of the mannifold instead of from the compressor housing, and it now holds a steady 5 or so psi. However I still get the annoying air coming out of the BOV vent noise. I can feel the air come out, and I can tell that the valve is opened a little bit allowing air from the intake to flow through. It closes as soon as any throttle is applied though. It's like the spring got weaker all of a sudden.I cannot tighten the adjustment screw, b/c if I do I get compressor surge. It also seems like I am pulling a little more vacuum at idle than I did before, 22-24 in/hf instead of the 20-21 before. What do you guys think this means? Thanks.

reignofchaos

so doing it on your manifold helps the pressure dropping???

ok i gotta try this

CLUNKER

the reason you bov is slightly open is cuz blow off valves open using vacuum thats why they open when you let off the throttle cuz your car stops seeing boost and goes back to vacum. it should be normal. someone correct me if im wrong.