Hi,
im thinking of replacing my old w/g and im wonder should i go for a bigger size w/g or remain the 38mm size for my 1.6bar of boost?

Pls kindly advise.

Thanks

 

Generally the more boost you run the less need there is for a large WG.

Purpose of the WG is to consistently control boost, so larger gates are used to prevent boost creep or spikes depending on the setup, hence to run a low amount of boost you may need a very large gate.

So in question, what boost are you running now (future is 1.6bar), and do you have any current boost concerns?

 

Yeah I am wondering the same thing as GTijoejoe is. Are you presently running 1.6 BAR and your current gate is controlling boost well. Then why change? Or, are you going to be increasing boost level from whatever it may be presently up to 1.6 BAR? If you present gate is controlling peak boost well at 1.6 BAR ...then why change.

What turbo are you running? Isn't it a 30R? What gate is on there right now? Are stiffer springs available for your current gate? It seems to me that a 38mm gate should be more than sufficient to control peak boost on either the 3071, or the 3076.

 

Do you happen to have a pic of the actual way your WG is mounted on your car? If you go to a larger diameter gate will this require a different weld flange?

 

The opposite holds true as well don't you think? The less boost you run, the less need there would be for any wastegate at all, large or small.

 

Actually, running less boost means you're venting more pressure around the turbo. Venting a greater proportion of exhaust gas requires a larger WG valve to maintain adequate control.

In this case, a 38mm WG will be fine.

 

Less means more?

 

Thank you Guys for sharing.
Im using Turbosmart 38mm W/G and boosting at 1.4 bar at the moment.

Yes, the WG holding boost perfectly with minimal boost taper til now.

Yes, my current wg is preloaded with 1.4bar of spring (dual) rate as im running without the ebc most of the time.

The reason i plan to change the WG is bcos ive been using the wg for more than 3 years now and plan to increase my boost up til 1.8bar.

 

Btw, my current external WG setup is the Profeb B II (NC) port to the pressure source (im taping the pressure source from the intercooler piping just before the intercooler from the compressor side as it is much nearer to the WG) and what i wonder is can i tap the pressure source directly onto the WG without going thru the solenoid since im not using the ebc?
Will this improve the turbo response and holding boost better?

Picture attached.
From the pic you can see that there's a Tee which connecting the pressure source, WG port and to the boost solenoid and after the solenoid back to the WG.

Please advise

 

Yes, less is more. Think of the extreme, if you have a tiny wastegate like 0mm (not having one at all), your boost would skyrocket 40-50+++psi. If you had a giant wastegate or straight up exhaust leak, you would never build boost.

You can bypass the EBC, boost source straight to the WG no problem to run off spring pressure alone, hook to the bottom port of the WG.

 

Thanks GTI Joe,
ok will try taping direct the boost source to the wg bootom port but how about the wg upper port? Do i need to tee off the upper wg port?

Just wonder will it improve boost response?

 

Is your external WG flanged at the manifold collector? That is, is the wastegate flow sourced pre-turbine? Just trying to visualize.

 

I disagree with the blanket statement in your earlier reply that a larger WG is more necessary at lower boost levels whereas a smaller WG will suffice at higher boost levels. That is just incorrect. But, I will not clutter the OP's thread with what would be essentially a divergent discussion.

 

Hi Sparky,
yes the WG flange is at the manifold itself and the WG flow source is taping from the i/c piping just before intercooler (near to the air-con compressor) from the compressor stretch which i stated wrongly on my earlier post.

 

You are 100% correct, its a visualization, that statement could certainly confused misinformed people if taken alone and not in context with the rest of what has been said in this discussion, it really depends on exhaust energy.