I am currently running a Forge VTA dump valve on my 99UK Impreza. I run my car at Crail when I can but I have been told that,not only am I a tart for wanting the chuff noise but it can actually make the car slightly slower! Is this right? Is a recirc valve better for standing quarters? Cheers all

 

Does Nobody know?

 

There's certainly no advantage... the best is no dump valve at all, of course

 

the VTA will only have marginal loss compared to a recirc.

the idea of a DV is to release excess pressure on the turbo when you rev down. As the engine butterfly closes all the air that the turbo (that is spining like mad) has no where to go. it will end up pressurising the system and making the turbo work harder, stalling the turbo. a VTA releases this pressure to tha atmosphere, letting the turbo wind down at its natural rate.

a return valve reflows the air before the turbo. this creates a higher pressure before the turbo, and acts as the exhaust gasses do on the other side, spinning the turbo up.

so, if you understand what i route (which i barley do) then a return valve keepd the turbo spinning at a higher rate, alowing the turbo to spin up quicker... hence the little more performance...

no BHP difference tho (but better curve)

 

...unless you slam it between the gears (like I'm guessing you would be with what you're talking about), when the boost shouldn't actually have a chance to drop - the effect is that the car keeps pulling when you take your foot off the power. Works well - but not much fun in traffic!

 

judge the vet to atmo bugger up the mixture so you get worse pick up after gear change CAR run rich I run reci FORGED with soft spring very very good.still get a good sound to.

 

If you're quick with your changes it doesn't seem to be any different. Of course, I've got the dawes which gets the turbo active very quickly so it feasible this is hidding any Forge disadvantage. Well worth if for the noise

 

Saxo Boy
You finally fitted it then?
Even after the good Dr.s advice..........Still. Hope you're enjoying it.
Steve G.

 

I bought a Forge VTA before Christmas. Sold it just after, following a discussion with Dr J.B.

 

SG72..

He fitted it all by himself and didn't even need a hand from anyone
Sounds cool anyway

 

All I needed was your tool sipie.............can I say that?

 

Sg72 - see 'scotland forum'

 

Ooh I'm such a nasty man stopping all you Rice Boys having your tunes

 

LOL at rice boys - last I hear you DV sounded the gayest of the lot

 

Kenny

Only winding you up mate...... sure you would have got there in the end