Re: way to test wastegate?
 

With fuel line and vacuum line. It's not going to be that reliable/accurate. The best way to do it is with an air compressor and a regulator. Set it to less than 20 psi and guesstimate as the needle moves up.

Re: way to test wastegate?
 

Use an air compressor with a regulator.

1: Turn it to about 15psi (no factory one should be higher really)
2: Hook you WG to it
3: It should be wide open
4: Slowly turn down the regulator releaving pressure.
5: Watch both the WG and you Guage on the regulator
6: Once the WG starts to close find the sweet point where it just opens and just closes.
7: Look at the guage on the Regulator and that is what you WG is maxed PSI at.

You can do it in reverse increasing pressure also. Most Regulators are High PSI (Accurate from 10psi to 150psi) so You may want to use a lower guage. They re only 99cents at a surplus tool store.

Re: way to test wastegate?
 

I used a small airbrush pump to testa few today. IHI RHF55 VF39 (STI) starts at 8 psi and is completely extended at 14 psi. Then I tested my used Bullseye Power that I bought on eBay for $1.00. they retail for $100 but this one had a dent (superficial and was purely cosmetic) that opens at 18 psi and is completely stretched at 30 psi. I'll simply change the armature and be happy holding 18 psi all day.

Re: way to test wastegate?
 

remeber that exhaust gasses are pushing on these things, so im not too sure calculating this way is gonna be very accurate

Re: way to test wastegate?
 

Wrong. Boost pressure from the compressor is what is used for internal wastegates. PSI is PSI is PSI and 8 psi on a bike pump will still be 8 psi on a turbos compressor.

Re: way to test wastegate?
 

Yeah. Mine was off by a pound.

Re: way to test wastegate?
 

i guess its internal then? i was confused because its on the outside of the turbo, but ya its bolted directly to the compressor so...

Re: way to test wastegate?
 

Wait a minute. Are you talking about one of those arcaeic OE recirculating valves? If so there is a big difference between a recirculating valve/bov than a wastegate. Wastegates are found on the exhaust side and internally would mean that the flapper in integrated within the exhaust housing. Externals are mounted in the exhaust tract to stall the turbine.

One works with vacuum and the other works with pressure. Big difference,.

Re: way to test wastegate?
 

you misunderstood me sir...i know how an internal wg works, but what i was saying is not to forget that exhaust gasses are pushing on the flapper and that may skew your results when tesing via a pump, since that element is left out.

Re: way to test wastegate?
 

Fair enough, but that isn't the point. The wastegates actuation would/could be skewed while installed on the car. Using pressure to the wastegate while it's off is going to give you the most accurate account of when it actually opens, not the other way around.