g60 isv boost bleeding function

[steveo29 0]

ive read on a few posts on various forums that the g60 isv serves another function, it bleeds excessive boost that the ecu cant supply fuel for :oops:

 

well if this is the case, whats the point in in having mega boost/smaller pulleys if the isv just vents it off anyway

 

my car currently has a jabba one way valve, which i assume disables that function

[catch_twotwo 0]

The ISV bleeds the excess boost when you come off the throttle I thought. Although it also bleeds at high boost. Although I'm running a stage 4 charger with an SNS chip and 68mm pulley and getting 15.5psi out of that.

 

The ISV doesn't bleed excess at boost until it hits a higher level... For some reason I have the number 17 in my mind, but then again I have memory problems so that could just be the number of Euro's i have in my bank account.... :lol:

 

The ISv only outputs... so a oneway valve would either be A) useless B) venting excess boost ;)

 

Some people reroute this back into the engine, but that's not a great idea (search for info).. Usually it vents back into the charger (warm air.. so not very useful)

[exturbo2003 0]

i think you will find the chip controls the pressure that the isv bleeds excess boost so if you put on a smaller pulley and chip it this will be taken into account

[selbekk 0]

when you're thrashing your car, and suddently want to change gears (and while doing that, step off the throttle and smack the clutch in), there will be a lot of excessive pressure (since the g-lader still keeps spinning). This is vented through a second butterfly in the throttlebody, and is further ducted through the boost return system which recycles it. Or out in fresh air if you remove the boost return system, which gives you that nice wooooooooooooooooooo (you could keep on going here) ooosssssssch sound.

 

The ISV leaks air past the intake butterfly on idle (right?). I've also heard something about the ISV venting excessive pressure on high boost levels (i.e. bigger pulley). That's why you use something like a ISV re-route kit (which I have no idea what does), or even better, just smack on a small air filter on it. Problem sorted. Now you just have to go through mcd's and order some fries and you'll be well chuffed. Seriously though, there are a ton of info on this page somewhere I think. :D

[W3RKD 0]

I added this to the forum some time ago -

http://the-corrado.net/.archive/forum/viewtopic. ... =isv+bleed

[steveo29 0]

hhhm sort of clear it up a bit darren

 

so theres no point in having lots of boost cus the isv will vent it?

 

and have you made in progress in dealing with it

[VR6 0]

Think we can keep this to Darren's existing thread as it's already got 3 pages of info. Unless CC's been posting in there, in which case it's probably 3 posts of info and some milf pics.