my Tial external wastegate has a red large spring in which is 10psi. iirc this dont mean 10psi of boost it opens? what boost would this spring handle as im going to be running about 2 bar?

 

pretty sure it does mean that the spring can only take 10psi of pressure before it gets compressed!like any set up you just beeld off the excess boost until u get to ya set boost then allow the actuator to see 10psi

 

The harder the spring, the less duty you run on the boost control valve.

If you ask me, you want to keep the deficit between the two as low as possible. My Tial 'gate is sprung to 1.5 bar, however that does mean it's the least boost you can run.

 

ok so i can still run my 2 bar but the least i can run is 15psi?

 

Well, I can't comment on Cossie gay boost control, but take my setup for example. My 1.5 bar spring results in a minimum pressure of around 1.4-1.45 bar of boost. I can then use a valve to allow more boost on top of that. So, valve off is 1.4 bar, valve at around 40% duty makes around 1.8 bar.

If my wastegate were sprung to 1.0 bar, it might take 80% duty on the valve to achieve 1.8 bar and the more you ask the valve to do, the more it can become unstable.

Thats my take on it.

 

so you must have a large and a small blue spring in yours. i need to get a stronger spring really as ill never want to run anything under 20psi. it was a pain trying to get the red spring in and bolting it up at same time let alone a stronger spring

 

your min boost would be 10psi i would say as that your spring rating

 

im running air injectors but would prefer a stronger spring in there so i dont have to use a lot of duty to get to 2 bar

 

ah ok i am running twin airs as well but running a 14.5 spring -34 are u on oe ecu?

 

The more duty you run, the finer the resolution, the better the control... as long as it's mapped properly..

 

the spring rates you require are more to do with exhaust back pressure when running high boost

 

im running Emerald on a MSD Single Air injector setup

 

If I want to run the minimum of 6psi and maximum of 14psi with an external wastegate do I use a 6psi spring and use a manual bleed valve stop the wastegate opening to allow 14psi?