i want to fit a dump valve to my :99 turbo but my brother inlaw who has a evo 6 was told they sound good but thats it.They told him it has no advantage on performance etc so your advice if you have one or no someone with one would be very helpfull cus im wet between the ears when it **** to this stuff thanks in advance for your help

 

Your mate is correct, no performance gains at all and can cause problems.
Stick with the OE valve and leave well alone.

The VTA can cause overfuelling causing borewash (excessive fuel in the cylinders) which has to go somewhere normally into your oil causing poor lubrication which can then drag a piston skirt and cause piston slap.

Zippy

 

[QUOTE=ZIPPY]Your mate is correct, no performance gains at all and can cause problems.
Stick with the OE valve and leave well alone.

The VTA can cause overfuelling causing borewash (excessive fuel in the cylinders) which has to go somewhere normally into your oil causing poor lubrication which can then drag a piston skirt and cause piston slap.


cheers zippy thats that put to bed then your a star

 

I had an HKS dump valve on mine and decided I didn't like the sound so sold it. When I took it off the car and put the old one back on, the car ran much better. It was so much smoother. I hadn't realised how lumpy the HKS had made the car.

I have however lost the pops and bangs.

 

I'm lovin it....hhahahaaaaa

if ya get chance follow this one through......

http://bbs.scoobynet.co.uk/showthread.php?t=421974