Charge Relief & Blowoff Valve

[bnaellis]

Gday folks,

While talking rotaries and staring at each others engine bay the othe rday my mate recognised that my charge relief valve and blowoff valve are the wrong way round. Needless to say I checked with about another 5 fd\'s right he was. Is this detrimental or doesn\'t really matter. It\'s been like this for over a year now and more than 13,000 miles.

rgds

[richrx]

ye your loosing 250bhp:rollin

only jokin, i dont know

no help then sorry:cool

[Fish]

And how long have you been driving the FD??? :p

Dan

PS. Dont know the answer to this one.

[John Yorke]

Hi Brian
I do know that when I first fitted my dump valve I had both pipes plumbed into it - what happend? I had a very hesatant 2nd turbo. Are you having any boost issues? if so would recommend re-plumbing your valves.
Hope this helps
Regards
John

[DRAGON]

They are both the same, they do exactly the same thing, which is open when vacuum is applied to the top nipple, its just that they do it for different reason.
Charge relief is designe to pre-spool 2nd turbo and the dump-valve pre-vents the compressor blades from stallling when you back of the throttle.

[bnaellis]

Cheers Ross,


Nah John boost is perfect. I thought maybe it was a cheap mod or something that got me a little more boost than go faster stripe would of:mad:

rgds

[richrx]

go faster stripe?  no way. i found the best is a max power sticker 10"X10" 240bhp+:rollin

[db2boy]

Hi Brian, everyone,
      I would look into this a little further! The valves are not the same and have different operations at different pressures. I have mentioned this to doubters in the past and can be proved with a simple vacuum tool.

The way I always think about this to make it simple is one is open or shut to prevent compressor surge, i.e. BOV or ABV - the other (CRV)  has a couple of variations of opening to bleed air from the secondary to control spool up.

I also have thought in the past Mazda kept the colours different between the 2 seemingly identical valves so as to avoid mix-up when the system was being worked on. Additionally the workshop  manual specifies a check for the CRV but unless I missed it Ive not seen one for and ABV - why would one have a check procedure and not the other if they were identical?

Just my thoughts.......

Rgds

Ant

[bnaellis]

mmmm,

Cheers Ant, interesting. I will check on my pfc commander over different kinds of driving conditions my boost, and shall swap the too valves around and do the same again and then play spot the difference. I guess I should be losing out on a bit of boost they way it is set up now, we shall see.

rgds