Reversing the recirc dump valve

[dessimpson]

Hi all,

My car had an HKS SSQV dump valve on it when I got it which sounded like the chavviest (?) dump valve ever. I sold it and got a standard one.
After a few months I reversed it to get the little wastegate chatter noise which is discrete but quite nice

I've actually drove my car a fair bit over the past few months and I've realised I'm only getting about 160 miles to a tank. Is this to do with reversing the dump valve? My old evo 5 was running a lot more power and was getting about 200 to a tank.

Des

 

[richleeson]

if youve reversed it, it might not open as well as it should do meaning you will be slowing your compressor down between gears which might be the chatter noise you are hearing, if you are slowing the compressor down then you would get worse MPG
correct me if im wrong....

 

[fq-craigus]

I reversed my standard one before I replaced it sounded great wicked chatter

 

[bakes fq]

Does reversing it damage the engine in any way . ?

 

[Steve220]

Engine - no. Turbo - yes

 

[sponners]

mitsi turbos are pretty tough so I wouldn't worry about damaging it (unless your running silly boost)

and no it wont effect your fueling.

 

[dessimpson]

mitsi turbos are pretty tough so I wouldn't worry about damaging it (unless your running silly boost)

and no it wont effect your fueling.

Standard boost.
Must just be my heavy right foot then :sad:

 

[bakes fq]

Is it easy to do on the 9 with a standard dv?

 

[richleeson]

sure chatter sounds cool but its not really a good thing is it..., you want that air recirculating as best it can to keep that turbo spooling, the less it slows down the better for performance and for the turbo and for the whole effiency of the engine...

 

[fq-craigus]

That's why you have antilag

Na I turned my dv round ad it was leaking like mad anyway the standard 8 ones are rubbish so I gave it a go before I bought one

 

[richleeson]

have you got antilag on yours craig?

ive replaced my recirc with the metal one from an evo 9 as i heard the plastic ones where shizzle! think they are supposed to be fine at stock boost tho...

 

[fq-craigus]

I put a metal one on too. Yh I had it put on ages ago sounds good lol deffo a must. You can have it put in with your map I think its just some negative timing

 

[richleeson]

Nice! What bhp where you kickin out before your engine got poorly? I bet that antilag is great for when youve upgraded from the standard intercooler

 

[Steveyb_evo3]

Reverse to bov and u stall the turbo on gear change hence the chatter coming through the intake it will damage any turbo long term and higher the boost the quicker it will do it

 

[fq-craigus]

Nice! What bhp where you kickin out before your engine got poorly? I bet that antilag is great for when youve upgraded from the standard intercooler

Not sure on the power if I'm honest hence my Sig lolz. I have the decat boost controller pushing about 1.4 and the antilag which don't add anything, I was gonna buy a fuel pump and get rob to map the car the saw month it went wrong. Cars all working now get to c it tomos can't wait

 

[Ozy]

Dump valves r good recirc is the way forward although I got dual port turbo smart my car but if you WANa hear it then you gona have to bov or dual port but otherwise recirc

 

[tmus]

I took mine off completely and blanked the holes, it drives smoother for me without it.

I don't like the sound of dv, recirc or not.

 

[Ozy]

Every one to there own if you take it off completely what the benefit??? I mean is there any purpose to it???

 

[richleeson]

you have to have something there to relieve the pressure in the power pipe when the throttle valve is closed otherwise that pressure build up is going to act on the compressor, ie stalling it, removing it is not good for turbo life and shouldnt be any good for performance, but each to there own. point is.... yes its there for a good reason....

 

[sponners]

when people refer to the turbo stalling, its not actualy stopping the turbo (its the pressured air stalling across the blades.

imo you have less lag without a d/v as apposed to with.

imo the d/v is fitted as standard to reduce turbo wear and noise.