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  • 1 month later...

hey mate how do you actuate the screamer?

Poke it in the dump pipe?

Same as a normal wastegate; pressure signal from pressurized inlet tract overcomes spring pressure holding wastegate closed.

Open wastegate releases excess exhaust gas (in this case straight to atmosphere, rather than into the exhaust) reducing the volume of gas available to spin exhaust turbine; thus reducing inlet tract pressure and closing wastegate.

The "screamer" name is due to the fact that the unmuffled wastegate is extremely loud; basically like an open exhaust, while the wastegate is open.

I used a turbosmart 45mm wastegate plumbed in before the turbo, it just dumps excess exhaust gasses to stop the turbo shaft speed from increasing once 26psi is achieved.

I have since plumbed the screamer back into the exhaust which made the boost skyrocket to over 40psi, i dropped the controller down but the tune has changed completely, back to the Dyno again...

There must be a hell of a lot of excess gas from the wastegate!

Is it worth (or can you even fit) a larger dump/ front pipe set up to reduce the back pressure? Does integration angle of the Wastegate pipe into the exhaust cause the boost spiking?

Have you seen BOBBYr34's wastegate venturi set up? That wouldn't take long to fabricate... :blink:

post-49633-0-88438200-1313757661_thumb.jpg post-49633-0-58284800-1310467413_thumb.jpg post-49633-0-41323800-1310467527_thumb.jpg

Not telling you how to row your own boat by any means mate; just curious.

Cheers, Dale

They merge at the 4 inch cat body, not the best flowing setup but more than adequate IMO. The reason for the boost spike is the increased pressure in the exhaust compared to just venting it. Once the controller was setup again the boost level was fine but the tune is still out, especially as the turbo spools.

I will try and get a pic today when I remove the front pipe again.

HOLY FUARK how did i miss this thread!

the epitome of AWESOME!!!

i was just talking to my uncle the other day about getting a gigantic turbo for my stag. so it can just be a lag monster.

i can cruise around as if it was N/A all day and then open it up when i want to! lol

LOVE IT!

getting a gigantic turbo for my stag. so it can just be a lag monster.

I never said 500hp is ordinary, it simply isn't a lag monster with a modern turbo and decent setup. Personally I would prefer a slightly smaller turbo for street use on a heavy wagon.

Bolt an old T88 on a 25 or 26 then you will see what laaaaaaaag city is like.

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