tial wastegate question

[1fast97gsx]

I just noticed a picture of 98tsiawd's setup and liked how his tial wastegate is mounted:



Well I have a tial 38mm wastegate but I thought it had to be mounted reverse so the flange that has the dump now goes to the runner on the header and the flange that's on the header now has the dump coming off of it. That's how mine was mounted at least but if I could do it the same way as 98tsiawd that would save me some room under the hood.

Here you can kind of see how my wastegate was mounted:

[DSMJim]

The gate will acctually work in that position however here is the thing. The pressure of the exhaust will be fighting against the valve from opening. The wastegate is vaccum regulated (or boost) to open at say 10psi. If you also have 6psi of pressure in the exhaust manifold then going to delay the opening on the gate likely causing creep. It will likely have an effect on the operation of the valve because there will be a pressure differential from the valve having to pull open under pressure vs. opening easily with the pressure pushing on the bottom against the spring.

Another thing to note is your wastegate doens't really open at 10psi it starts to open at 5 and slowly creeps open fuly at 10psi to hold the boost at a particular level. It continues to open more and more as exhaust pressure and volume rise with RPM to keep boost at the desired level. If the gate is fighting to open you may see creep in the beginning as well because it will have a delayed reaction because of the extra pressure on the valve.

One other thing is the design of the valve is really only ment to have the heat from the exhaust on the bottom of the valve. Having it this way will have that whole chamber filled with exhaust swirling around inside and the entire stem of the valve will be getting really hot all the time. That may cause the valve to fail early as the heat is directly on the stem which will cause the diaphram inside to get a lot hotter. The other way around the exhaust is only in the camber when the gate is open which is not very often.

[1fast97gsx]

ok thanks for the quick response. 98tsiawd actually pmed me and said he switched his around now. Thanks.