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New owner first mod

Featured Replies

Hi, I pick my 60 plate wrx-s up on Friday and I would like my first mod to be a dump valve.

I know! Sorry!

I know people mention the vta ones can cause problems, so am I better off with an adjustable one like the TMF respons one, so I can have it 50/50.

Has anyone got any experience with the Collins Performance dump valves? They are just down the road from me and back in the day (cossie era) they along with Turbo Systems and Castle Performance were the daddies!


Wotcha and welcome - nothing worng with the mod, the collins performance option looks like the forge model.

 

Replace the recirc valve with the dump valve and see if it works - it will run rich as the valve operates but only momentarily - post some pics and let us know how you get on ;)

  • Author

Cheers Jay, would a performance panel filter help to prevent rich running?

Thinking probably not as the extra air will still be metered, and then missing during blow off.

thats exactly it ;)

 

but on a positive note if you ditch the catalytic converter the extra fuel can ignite in the exhaust and gives a lovely orange glow in the end pipes :D

  • Author

Think I might look for a hybrid one so I can adjust it to not run too rich


Gambit has one for sale at the mo not sure if it meets your requirements

  • Author

Thanks but I don't think it'll fit mine. Mine is a (shark eye?) new shape hatch

  • 2 weeks later...

Does running a VTA cause lean running for a split second when the throttle is reapplied? I would have thought when you vent to atmosphere, thus not pressuring up the turbo intake pipe via recirc, then air still being sucked in by the Turbo (that is being metered and fueled for off throttle) will be getting built up in the empty intercooler.

  • Author

Yes, I'm lead to believe it will go rich for a very short moment.

I managed to get one on ebay, it's an ex-display model from Scoobyclinic.

Turbosmart, which can be 100% vta, 100% recirc, or anywhere in between, so I'll just wind it to be mainly recirculating, to get a small dump noise

I run my VTA with a stiff setting on the spring so it mainly vents back through the Turbo. I've read that this also causes a moment of rich running but I don't understand how it's different to venting to the intake from the recirc valve. 


  • Author

Not too sure but I think if the pressure goes back into the turbo that's not very good for the turbo?

Someone else may know more though.

Not too sure but I think if the pressure goes back into the turbo that's not very good for the turbo?

Someone else may know more though.

The TD05 I run is a strong Turbo and at higher boosts the DV vents to air anyway. 

 

As far as a few of us worked out on another site air entering the turbo intake pipe from the OE recirc DV creates a pressure that blocks new air entering past the MAF which confuses the ECU. 

  • Author

Ok fitted my Turbo Smart Dual Piston BOV

image_zps192ecbf6.jpg

  • Author

Not convinced yet! It rests on the TMIC bracket (see pic below) and even on 100% recirc it's not! If you give it a bit it vents to atmosphere still. !Removed! loud on 50/50 lol. Not tried it all the way vta yet.

image_zps99c899c0.jpg

You have to run it fully closed then fully open and tell us if you notice a difference in running or pops and bangs etc. 


  • Author

Ok will give it a run some time this weekend

  • Author

Doesn't seem to make any difference to how it runs. No pops or bangs. When turned to softest setting it just vents at lighter revs, where as on hardest setting it only vents when you let off from higher boost levels.

Actually doesn't seem any louder between the 2 extremes. If you gun it then both settings vent to atmosphere just the same.

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