drewiee99 0 Posted May 11, 2007 are these any good on a slightley moded engine will it cause running probs? http://www.autotech.com/prod_engine_g60hp.htm SportTuned Boost Check Valve Quote Share this post Link to post Share on other sites
flusted 0 Posted May 11, 2007 Most people on here will say you need the isv to bleed off excess boost, fitting one of this prevents that. Im running without an isv with no probs. If your isv is prone to leaking when it shouldnt, you will lose boost Quote Share this post Link to post Share on other sites
Henny 0 Posted May 11, 2007 if you need one due to losing boost through the ISV, then you need to find out WHY you need one, rather than bodging a valve into the system to stop the boost bleeding off... I don't think that Bosch would spend all that money developing the Digifant system when a simple ball bearing in a conical tube would have done the job do you? ;) :lol: Quote Share this post Link to post Share on other sites
flusted 0 Posted May 11, 2007 but bosch dont expect you to stage 4 your charger and run smaller pulleys :wink: Quote Share this post Link to post Share on other sites
Henny 0 Posted May 15, 2007 wanna bet... The system was designed with the Rallye in mind which was a full on rally car running silly small pulleys on motorsport chargers... the system can happily deal with much, much higher boost levels than the standard charger can deal with simply by using a different MAP sensor... ;) Quote Share this post Link to post Share on other sites
Andyrado g60 0 Posted May 18, 2007 Hi guys! OH MY GOD! I think i can stop worrying. I have recently been to our friends at g works for an rsr, sns chip and 68 pully. The manifold started blowing on the way there so all the way back and untill i got the manifold replaced i diddnt give it much throttle. (well diddnt take it above 3000 to be honest because i had heard 1950's tractors sounding better) anyway new monifold and sounding sweet again. I was very impressed with the gains that the chip, pulley and rsr gave me, i have a boost gauge fitted and im seeing a touch over 1 bar of boost in third with foot on the floor at about 5000 prm, thats just over 14 psi isnt it? Is that good? Well occasionally (about 30% of the time) when i put my foot down the gauge will hit 1 bar for 3 or so secconds, then drop down to about 0.5 bar (with the pedal still all the way down) it allways drops and rests at about 0.5 bar and has been puzzeling me, thought it was a boost leak somewhere or the charger was ready to go! allthough it was only stage four'd 10'000 ago and all those miles it was on standard pulley. I hoped it was the boost leak! But with the cpu being down for the last few weeks i have not been able to get on the corrado forum for any length of time to have a look and make a post. So can i put this down to my isv being a bit dodgy then? and would you advise getting this check valve mod or a new isv? And is just over 1 bar good for a charger with 68 pulley, rsr and sns chip? Thanks very much guys! Quote Share this post Link to post Share on other sites
DanVW 0 Posted May 19, 2007 An important point to remember regarding these ISV check valves is that as far as your ECU knows it hits a set value for boost and assumes anything over is being dumped via the ISV it cant measure the boost and add extra fuel required for boost above the set value (just under 1 bar iirc), this could mean your engine running lean at full chat.... Not good! :onfire: Have a word with the guys @ Gwerks am sure they will give you all the pros and cons Quote Share this post Link to post Share on other sites
flusted 0 Posted May 19, 2007 Good luck to my isv for bleeding the boost, i dont have 1 lol Quote Share this post Link to post Share on other sites
Andyrado g60 0 Posted May 19, 2007 ahh right i see, so your saying that the isv check valve could cause the engine to run lean? I havent got an isv check valve on, so could my boost loss 30% of the time after a few secconds of full chat be due to my isv being a bit dodgy? Quote Share this post Link to post Share on other sites
peteTDI 0 Posted May 20, 2007 is the boost loss at the same rev range ie 3 to 4 k? Quote Share this post Link to post Share on other sites
Andyrado g60 0 Posted May 22, 2007 No i dont think so, when its "happening" it happens after a few secconds on full boost, but allways drops to the same place of the boost gauge. Then other times it will be fine and stay at just over 1 bar all the way up! Strange, i home its not my charger showing signs of it being ready for a re-build, it was only done 10k ago and all that time it was on standard pully, only recently fitted 68mm. Is 1 bar good for a charger with a 68mm and rsr? Quote Share this post Link to post Share on other sites