RDR Intake Pressure Tester for a Turbo 3000GT or Stealth

• Why Do I Want To Do This?

  • Ideally, your intake piping should be completely airtight. This eliminates vacuum leaks (where air is sucked into the engine other than through the air-flow sensor) or boost leaks (where air escapes after it has been measured by the air-flow sensor). Neither boost leaks nor vacuum leaks are good for engine health or performance.
  • This pressure tester is a little different than many of the ones that others have currently created. The difference is that this intake pressure tester does not pressurize the bypass valve outlet or the breather hose from the rear valve cover. As a result, it allows you to test your bypass valve for leaks, and it allows you to verify that your PCV valve and cylinder rings are preventing air from passing into the crankcase.




• How Often Should I Do This?

  • When you first buy your car.
  • Whenever you take apart significant parts of your intake piping or intake manifold.
  • Probably every year or so, depending on the heat and humidity of your climate. Hot or dry climates tend to cause the rubber parts of your car to become brittle more rapidly.




• How Long Will It Take Me To Do This?

  • The first time, including making your tester, plan on an hour or two.
  • After you've made your pressure tester and know the process, you should be able to test for leaks in 30 minutes.




• Anything I Should Do Prior To Attempting This Procedure?

  • Make sure you have all the tools/supplies you'll need.
  • If you don't have an air compressor, make sure you fill your portable air tank.




• What Mitsubishi Parts Will I Need?

  • None.




• What Other Parts Will I Need?

  • (2) 2" ID Rubber Pipe Couplings
  • (1) 9" Section of 2" OD PVC/ABS Pipe
  • (1) 1/4" NPT Male quick-disconnect air hose fitting with male threads
  • (1) Tube of RTV or other silicone sealant (optional, but recommended)




• Where Can I Get the Stuff To Do This?

  	Part	Company/Contact	Part Number
  	2" ID Rubber Pipe Coupling	Lowes Hardware	N/A
  	9" Section of 2" OD PVC/ABS Pipe	Lowes Hardware	N/A
  	1/4" NPT Male quick-disconnect air hose fitting with male threads	Lowes Hardware	N/A
  	RTV or other silicone sealant	Any Auto Parts Store	N/A





• What Tools May/Will I Need?

  • Air Compressor or Full Air Tank
  • Air hose with female quick-disconnect fitting
  • Valve or regulator for air hose
  • 10mm wrench, nut driver, or socket/ratchet
  • Drill
  • 1/2" Drill Bit
  • 9/16" Open or Closed Wrench
  • Hacksaw or something to cut PVC/ABS pipe

The Procedure

	Gather Your Materials
	Here are the pipe couplers, the pipe, the NPT fitting, and the RTV sealant.
	Cut PVC/ABS Pipe to Length
	You'll need about a 9" section of pipe. I trimmed mine down closer to 8", but anything 7" to 9" should work.
	Drill a Hole in PVC/ABS Pipe
	Pick a spot in the middle of your pipe and drill a 1/2" ID hole in it. It doesn't have to be perfect, but try to get it straight. A drill press is nice if you have one.
	Partially Thread NPT Fitting Into Pipe
	PVC/ABS is soft, metal is hard. Therefore, just shove the fitting into the hole and start turning. The metal fitting will cut its own threads in the plastic pipe and seal quite nicely.
	[optional] Apply RTV Sealant to Fitting
	If you want to be extra sure you get a good seal, you can apply some RTV sealant to the threads and the base of the NPT fitting at this point. Just goop it on there before you fully seat the fitting.
	Fully Tighten NPT Fitting
	Tighten that fitting down all the way with your 9/16" wrench. Once it stops, don't turn it much further since you don't want to damage the plastic pipe.
	Slide Couplings Over Pipe Ends
	Slide the couplings over the ends of the pipe. Loosen the outer hose clamps (that will attach to the car's piping) and slightly tighten the inner clamps (so they don't fall off the pipe).
	Allow RTV to Dry
	Technically, you should let it be for 24 hours. If you're in a hurry and are pretty sure you drilled a clean hole with your drill, then a couple hours should be sufficient.
	Admire Your New Intake Pressure Tester
	A few minutes' work and $15 isn't that bad, is it?
	Remove Your Air Filter and MAS
	Disconnect your air filter or OEM airbox lid and your MAS housing.
	Remove OEM T-Pipe
	The pipe that the MAS housing attaches to is shaped like a "T" - it has an inlet for the MAS housing and two outlets, one for each turbo. You need to remove this pipe. There are two hose clamps, one on each end, for the pipes leading to the turbocharger compressor housing inlets - remove loosen these clamps. There is a hose clamp where the turbocharger bypass valve (BPV, or BOV) connects to the T-pipe; remove that, too. Finally, disconnect the breather hose on the underside of the T-pipe and it should just come right out.
	Attach Pressure Tester
	Attach the hose couplings on your pressure tester to the two intake pipes that used to attach to the OEM T-pipe. Securely tighten the hose clamps on both the OEM pipes and the new PVC/ABS pipe on your pressure tester. You don't want that popping off around your garage. Now, connect your air hose to the NPT fitting on the pressure tester.
	Slowly Pressurize Intake Piping
	Slowly open the valve on your air hose or increase the pressure setting on your regulator. Some noises from your rubber intercooler hoses stretching is normal. Listen for any hissing sounds from your engine bay - those are generally leaks.
	Fix Any Leaks You Found
	Some rubber seals may need to be replaced, and some hose clamps may need to be tightened.
	Pressurize Intake to 15psi
	15psi should be a good target to make sure you have no leaks, as that is the maximum boost most BPU cars run. If you run more boost than that, then test it up to that pressure, too.
	Be CAREFUL!
	Overall, be careful while testing your intake system for leaks. Even at 10-15psi, a hose blowing off can have considerable force and cause injury to you or others. Always increase pressure slowly and check for any connections that seem insecure.