I have been having a problem lately holding boost. It all started with my profec b I thought it was broken cause my car would not hold boost but apearently it was not the problem. My car can handle 11psi but that is all, anything over that and the boost will fall back to the 11psi mark. I tried using my old 5lb actuator today thinking that maybe the 10lber was broken but it did not help. The only thing I can come up with is that I have a leak somewhere. I am repalacing my 2 elbows tomarrow to eliminate them and all of mt other couplings look to be fine. All my vac lines are squared away too. Could I have a crack in the I/C? How can I pressure test it with high enough pressure to see if it leaking? I am out of ideas as to what could be causeing my pressure loss. Does anyone have any ideas cause I am out?
Patrick
96 GS
14.14 @ 96.5 mph on 8psi 8 Nov.02
HRC kit, S20G, FMIC, Howell bottom end 8.6 pistons, S-FMU, Blitz BOV, P&P head, SS valves, lots more little goodies

build a boost leak tester. Go to your local hardware store and get a short piece of PVC tubing, around 2" or 2.25" in diameter, an end cap for the pipe, and an air compressor fitting to put in the end cap. Glue it together with PVC cement, and RTV the air fitting in the end cap. Use a coupler to mate it to your piping coming right off of the turbo compressor outlet, and pressurize with around 15 psi of air or so. Be sure not to put tons of pressure into the piping, like without using a pressure regulator on the aircompressor. Its normal for there to be very small leaks at the BOV, and the throttle body throttle plate shaft. You should be able to hear any other leaks, and even feel around for air leaking. Start here, and see what you can find. Leaks are usually the cause of boost fade, esp if you use the compressor nipple on the turbo as a boost source for your boost controller. Using an intake boost source for the boost controller, can help get rid of this issue, since it senses pressure in the intake, rather than at the turbo, which accounts for pressure loss from small leaks, and even the intercooler.

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)

Could I use the nipple coming off the top of the throttle body for an intake boost source to the b/c? If so what do I do with the nipple coming off the turbo, just cap it? I will also try to build one of those leak testers. Thanks as usual Matt
Patrick
96 GS
14.14 @ 96.5 mph on 8psi 8 Nov.02
HRC kit, S20G, FMIC, Howell bottom end 8.6 pistons, S-FMU, Blitz BOV, P&P head, SS valves, lots more little goodies

I jam an unopened soda can in the turbo intake, clamp it back down, and connect my air compressor to the nipple on the S16G. Easiest boost leak tester evar. Just watch out for flying coke cans if you pressure test over 10psi.

400whp or bust.