How does the stock waste gate solenoid work?

[ngnowner]

stock boost level

I'm confused. How would porting the hole help with this? Does it allow the puck to fit in the hole better or something?

Just wondering....and learning.

The wastegate hole in turbo housing will work well @ 13psi, factory boost level. When we start cranking up boost (and who here hasn't) the exhaust turbine creates more pressure than the stock size wastegate hole can handle, which can create boost creep. It did on my car. So enlarging the hole slightly should eliminate the problem. I also radiused the inner part of the compressor housing for better flow. All done with a basic dremmel tool on the car, not hard to do. I added a RJC boost controller after that as well. Now the boost stays where I want it, and i can watch the road instead of the gauges :biggrin:

 

[mikestertwo]

Does this mean you can achieve more boost for less actuation of the wastegate or just better control over the engine rpm?

....i'm learning too....

It gives you better control. An engine is an air pump. The original setup was designed to control the boost with a certain maximum amount of air flow through the exhaust. When the engine is modified with ported heads, manifolds, bigger cams, throttle bodies, free flowing exhaust systems, etc. the engine is pumping a lot more air for the same rpm. The original wastegate cannot handle the much larger volume of air so more of the exhaust gases are forced through the turbine for a given rpm increasing boost. Opening the wastegate port allows more gases to be bypassed so you can control the boost at these higher flows.

 

["Turbo-T"]

The wastegate hole in turbo housing will work well @ 13psi, factory boost level. When we start cranking up boost (and who here hasn't) the exhaust turbine creates more pressure than the stock size wastegate hole can handle, which can create boost creep. It did on my car. So enlarging the hole slightly should eliminate the problem. I also radiused the inner part of the compressor housing for better flow. All done with a basic dremmel tool on the car, not hard to do. I added a RJC boost controller after that as well. Now the boost stays where I want it, and i can watch the road instead of the gauges :biggrin:

Thanks for the clear up, now if I may ask what are the signs of boost creep?

 

[ngnowner]

the creep

Thanks for the clear up, now if I may ask what are the signs of boost creep?

I started with adjustable wastegate rod and turned the boost up to 15psi. (from 13psi). Then in 3rd gear around 70mph on a WOT run it would start to rise and get to 18psi by 85mph, I lifted at that point. Came on the board and was educated about boost creep and how to fix it. Ported the wastegate hole, and got a manual boost controller.

 

[zeus87gn]

It gives you better control. An engine is an air pump. The original setup was designed to control the boost with a certain maximum amount of air flow through the exhaust. When the engine is modified with ported heads, manifolds, bigger cams, throttle bodies, free flowing exhaust systems, etc. the engine is pumping a lot more air for the same rpm. The original wastegate cannot handle the much larger volume of air so more of the exhaust gases are forced through the turbine for a given rpm increasing boost. Opening the wastegate port allows more gases to be bypassed so you can control the boost at these higher flows.

I get it!
Thanks to everyone here for posting these questions and replies!
This board is great!