I have a 2004 wrx sportwagon and need to know what size blanking plug to get so i can fit my dump valve? Can anyone help?

Thanks

Gaz

 

yes, undo the pipe and measure it for the most accurate answer.
2 minute job that means you wont get it wrong at somebody else expense

FWIW, and I don't advocate this in anyway whatsoever, I used a champagne cork and a jubilee on a reducer

 

if its the same as a classic its 25mm and halfords do a rubber gromet that fits perfectly for £1:80