External Wastegate ???

[DSM90AWD]

which one do i go with... and how are these explained ?

Spring pressure denotes the minimum boost level the wastegate can hold. So depending on what min boost level you wan to run will drive which spring to purchase.

Note that Tial springs come in two sizes small and large. Small and large springs can be combined to increase the minimum boost level above 1BAR in the 35/40, 38, 44 and 46mm models.

RRE has a nice chart of the various Tial spring options

 

[BlckTalon]

The Evo III 16g turbo has an internal wastegate correct? And if you add, say a 38mm tial wastegate to the turbo manifold, do you just leave the internal alone? I'm a newbie when it comes to this so be easy on me. But I was thinking about the Slowboy racing equal length turbo manifold with the 38mm tial wastegate on the manifold with the Evo III 16g. Is that all possible?

 

[DSM90AWD]

The Evo III 16g turbo has an internal wastegate correct? And if you add, say a 38mm tial wastegate to the turbo manifold, do you just leave the internal alone?

If you add an external wastegate off the manifold you would need to to have the stock flapper door welded shut as the external would now take over that function of bypassing exhaust gas away from the turbine wheel.

Could then sell the stock actuator for a few $ to offset the cost of the external

 

[WatchItExplode]

Would it be worth the effort to weld in a piece of metal in the turbine housing to completely block off the entrance to the internal gate, so its as if it were never there? Or am I just making a simple process way too complicated?

 

[DSM90AWD]

IMO not worth it, even if it could be done without risk of the welds cracking and metal chunks dislodging into the turbine. Buschur and RRE have been simply welding the WG closed for years when adding an external to the manifold

 

[Turbocharged]

Does your turbo currently have an adjustable wastegate actuator? Try loosening the tension in the wastegate spring. This will help A LOT and nobody ever seems to do it.

Before buying an external wastegate, try driving the car with the wastegate actuator arm disconnected. This will effectively leave your wastegate open at all times and will give you an idea of how low of a boost setting your car can run (do this with the boost controller off). If it still creeps then yes you need an external WG, but I supsect that something isnt setup correctly.

How big is the WG flapper? Was the WG hole ported? Are you sure the WG is opening all the way (actuator too tight)?

I am able to run 13 psi on my internal 50 trim with 3" turbo back exhaust. This is with a tubular O2 housing. This was after loosening the WG actuator to finger tight. You should be able to do better than 24 psi with your O2 dump

 

[lauj2gdsm]

its probably the boost controller. my friend has the same one you do, does the same crap... creep like hell. he switched it with a manuel and it hold boost fine.