[Guest]

Sorry Andy I can't see those diagrams but no doubt its what I was thinking (sorry but it got too late last night to do mine).

To test if the reversed dump valve does open how about temporarily disconnecting the return pipe from the valve to the intake, blanking the hole in the intake end and then tape some tissue paper over the valve end. If the dump valve does actually open when reversed then you will hopefully find the tissue paper ripped after testing. Just a thought for some basic home engineering, not very scientific but it will at least prove if the dump valve is opening.
Actually thin tin foil might be better than tissue paper (Kit Kat wrapper springs to mind) as at least its gas tight but easily tearable (and you get to eat the Kit Kat )

I think I have been watching Scrapheap Challenge too much

 

[Guest]

That ought to do it HH6! Who's going to try it then?

 

[Guest]

dont know as much as you guys but heres my 2p worth,
Tried reversing the valve,stopped the standard noise got a fluttering sound instead,didnt notice much difference in performance however did feel slightly more responsive. I think the sound is caused by the wastegate because it sounds the same as the actuator on my dads cossie only quieter and wastegate actuators make that fluttering noise,with valve in standard position or hks valve on noise is gone,get dump valve noise instead.however when the hks was fitted noticeable increase in throttle response and boost held at a higher level and dropped off less quickly,with sandard valve reversed no noticeable difference in boost.for all you sceptics to test wether the hks valve really made a difference i refitted the standard valve in standard positon and reversed on my dads evo and it was DEFINATELY slower through gears and less responsive. hope this is of some use. BTW this isnt an advert for the hks valve and im not recommending you go buy one just passing on my experience.
i'm really tired so excuse any mistakes

 

[Guest]

err.....NOT ME !

Seriously guys, it would be great to put this issue to bed,
atleast then we can offer proven advice to people who ask
this question again.

The only reason I can give for why you should invert your valve is.....
if it was so safe, Mitsu would have done it in the first place !?!?!?!?


I may just un-invert my recirc valve at the w/e to see if there is any
difference, ive also got an HKS SQV in stock, may just have a go
at that too.....then I can spit flames and turn my yellow bumper orange and amp;lt;VBG and amp;gt;

Justin

 

[Guest]

Bu99er, im tired too, that should have read

The only reason I can give for why you should NOT invert your valve is.....
if it was so safe, Mitsu would have done it in the first place !?!?!?!?


zzzzzzzzzz Justin

 

[Guest]

Original Post:
The only reason I can give for why you should invert your valve is.....
if it was so safe, Mitsu would have done it in the first place !?!?!?!?

I tried it for a while early this year, did notice a definite difference in spoolup but no noise difference, although that's maybe because I've not modified the induction setup.

What I did notice was that the car became harder to drive smoothly coming off the throttle, for that reason alone I could see Mits going for the more linear 'normal' arrangement. It's certainly why I reverted back to standard, there being no concrete evidence to suggest it does any damage.

I've heard this fluttering noise being variously explained as compressor stall, wastegate pulsing and the dump valve itself opening and closing rapidly - I'm going to get to the bottom of this

 

[Guest]

HH6,
You've definitely been watching too much scrapheap challenge but I think I'll give it a go if I can find a suitable plug for the intake.
I think that just to be on the safe side you should use lots of KitKat wrappers (or is that because I'm a fat b******)
I probably won't get around to testing it until next week due to moving house at the weekend but I'll let you know when I do.

Andy