N12 Turbo Forums

Hey guys i mounted my turbo and wastegate up, had to drill some holes in the CHRA for bracket but silly me didn't think to test the wastegate pressure before doing it all. I tested it now and it seems to be a 12psi spring that only really has a nice full opening at 17ish psi onwards. Will this be bad on a stock ecu? I don't really feel like leaning out my brand new engine. Its meant to be one of those adjustable wastegates with the winder but the turns don't seem to do anything.

Would keeping the wastegate partially open be an effective way of lowering spool and preventing overboost? I don't mind buying a new one that has a lower pressure spring but just want to sus out any options before spending 100+ bucks.

Cheers.

stock ecu will not like anything over 14psi thats for sure. even with higher fuel pressure you will be on the lean side.

Cheers shane, i guess running it straight is a no go then.

But fortunately i think i just found a great solution! With a couple of washers and nuts you can use a compressive spring to aid with force required to open the wastegate like so:



Brilliant! ill have to sus out a spring and give it a go next weekend.

rubixcube101 wrote:Hey guys i mounted my turbo and wastegate up, had to drill some holes in the CHRA for bracket but silly me didn't think to test the wastegate pressure before doing it all. I tested it now and it seems to be a 12psi spring that only really has a nice full opening at 17ish psi onwards.
Cheers.

Is this testing done on the car, or with a air supply and pressure gauge?

I was taught to state wastegate pressure at the pressure it takes to 'crack' the valve itself. That is, we used to dial up the pressure until the wastegate flap was able to be spun by finger against its seat, at that was the pressure it was 'rated' at.
If the wastegate cracks at 12psi, that is all the engine will see give a psi or 2.


Damo

Car isn't running just yet so testing was done with air compressor and used a boost gauge to regulate the pressure while testing. I'll have to check whether the gate spins or not, but 12 psi is the pressure at which the gate begins to open. If that's the 'crack' that your referring too, +/- a few psi then this is good news!

I haven't had much experience with a turbo car so wasn't sure exactly as to whether the turbo can continue to gain boost once the gate is remotely opened.

Found this off an ebay site and i'd say the spring is similar to this one rated at 0.8bar/12 psi. Obviously the spring will continue extend with the increase of pressure as there is greater force being applied, but why do they bother to give data then for a 1mm extension and a 5mm extension of the actuator rod if the engine won't see anything past the inital pressure for extension? If the pressure will not increase past 12psi then this is no issue at all... obviously don't want to be overboosting to 16psi though.


Cheers guys.