just fitted a gfb stealth bov to moy 06 wrx but have no idea of the spring tension on it and what setting have the main valve set for 50/50 atmo but get a small backfire when i back down on the revs any ideas

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such is brake dust

Don't think there is much you can do .. The whole point of the 50/50 Hybrid design was to try to prevent the issue you are having. Best thing to do would be to tighten the spring so that it opens for the shortest period of time, but still allowing it to vent properly - Not forcing air back in the opposite direction.

I think it may be a tricky battle to win though. Make sure that the BOV is fully closed when the car is idling - Tighten the spring up. I've got a GFB WRX Hybrid and have it as tight as it will go.

I get the occasional pop on mine, but not enough to warrant removal.

Richard

Id set it for the tightest spring tension. New WRX dont like venting BOVs. Massive overfuelling on throttle lift off causes the backfiring.

A tighter spring tension will mean slightly less air will pass through the bov, but you will still get over fueling and your overall fuel economy will drop also.

I have a GFB hybrid. Used to have it on 50/50 then full atmo, but now full plumb back.

My fuel economy has already improved significantly since going back to full plumb back.

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RS Liberty - Because WRX's are only good for parts...

thats what i thought fuel economy has dropped easy 80k's at tank at the moment

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such is brake dust

2nd that motion.

Mine's set on full atmo, nothing but a pain in the ass. Backfires like a blabbering bitch and fuel economy is significantly reduced also. Unless its for wank factor, take it off and revert to stock

If not, then aim to have it close just prior to reaching idle. Mines set to about 3 turns off full I believe. Start at the lowest spring tension and tighten it up slowly. If its at full tension and the valve stays open at idle, then you're probably gonna need a stiffer spring.

Please correct me if I'm wrong.

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TD06 - Oink.

Feral, I ran with turbosmart full atmos bov for a few months, got crap fuel consumption, ran rich as and backfired plenty. Unless you just love the sound then I would suggest you ditch it and stick with the stock bov.

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Funny looking German Subaru

run the stockie mate... it makes the car run like a pig