Sandy 0 Posted February 13, 2004 Hello Folks What would be the maximum boost in bar you would get from a standard charger & pulley on a g60 ?? What would be the maximum boost in bar you would you get from a stage 4 charger & 70mm pulley on a G60 ?? Sandy Quote Share this post Link to post Share on other sites
LowG 0 Posted February 13, 2004 not sure but on a fully ported flown charger with rsr outlet,front mount IC and 68mm pulley no cam or head porting i get 16-17 psi cant remember that in bar. Quote Share this post Link to post Share on other sites
h100vw 0 Posted February 13, 2004 I think VWs service limit is 8PSI for a std setup. 0.5-7BAR. a 68mm pulley and port job would get you 1BAR as a rule maybe a touch over. 1 BAR is 14.7 PSI if memory serves me correct. Those figures are taken at fairly high revs too. In excess of 5K..... Gavin Edit.. Like LowG says, cams and head work lower the 'boost' as boost is more a measure of restriction than 'flow'.. FLOW is all important in making power. Quote Share this post Link to post Share on other sites
beavis 0 Posted February 13, 2004 A healthey stock charger, on stock pulley will kick out around 9-10psi on a accurate gauge. 1 bar equates to around 14 psi, so you should be looking at 0.6-0.7bar. With a 70mm pulley and S4 12-13psi. Quote Share this post Link to post Share on other sites
LowG 0 Posted February 13, 2004 boost at about 4k rpm will be about the same as at 5k rpm as after that you wont get any more boost due to belt slip, no matter how tight the tensioner is set up it will always slip in higher revs, only solution is a toothed belt system. Also the stock intercooler and stock piping is not very freeflowing so you will loose some boost there due to resistance before it goes in the engine. Some intercoolers are known to flow pretty well even at high psi. But i should say a 15 psi figure should be abuot right for a ported charger on 68mm pulley rgds migs Quote Share this post Link to post Share on other sites
Sandy 0 Posted February 13, 2004 Cheers Sandy Quote Share this post Link to post Share on other sites
beavis 0 Posted February 13, 2004 Little more to the equasion than purly belt slip alone. The Management on the G60 actively bleeds boost off as a safty net if it detects pinking from the knock sensor and anomolies from other senders, so although belt slip is a major issue which is addressed by toothed belt systems, belt slip is not the sole reason that causes boost presure to plateau. This is a issue Myself Liam and Darren are reseaching at the moment. Certain cars bleed off quite drastically, others not at all, regardless of set up. Quote Share this post Link to post Share on other sites
Sandy 0 Posted February 13, 2004 How much would it be for a toothed belt system for my G60 ?? Sandy Quote Share this post Link to post Share on other sites
LowG 0 Posted February 13, 2004 Thats why you should have an isv reroute, at 15 psi i believe the iddle stabilising valve bleeds boost off, so for high psi an isv reroute kit is a must, that way you will worry less about the faulty isv valve as if any air is lost at any time its just dumped into the intake tube. rgds Quote Share this post Link to post Share on other sites
beavis 0 Posted February 14, 2004 Reroutes do not solve the problem of boost bleeding off as you are just feeding the bleed off boost back in to the manifold pre throttle still creating a open circuit. Check valves stop the boost bleading off physically, but they do not stop the ECU retarding the ignition timing which it also does when it enters the 'overboost cycle'. In some circumstances they exagerate the problem as the ECU detects no drop in boost pressure when it is trying to bleed what it sees as excess boost off via the isv, so retards the ignition timing even more. So although you maintain boost pressure, the car is not maximising it as the ignition advance is severly retarded. The ISV's are not faulty, just doing what they are being told to do by the ECU. It is a managment issue and cannot be addressed by just rerouting/bunging the ISV. We are addressing the anomoly by adjusting the management so that the cycle does not begin in the first place, therefore boost pressure will be maintained as the ISV will not bleed off and ignition timing will not retard, both aspects are then addressed. More to follow. Quote Share this post Link to post Share on other sites
W3RKD 0 Posted February 14, 2004 to save this going off topic i have started a new thread on idle stab valves.. :D "much achievment made! little bit more but not to much!" :D click here ... http://the-corrado.net/.archive/forum/viewtopic. ... 4664#74664 Quote Share this post Link to post Share on other sites
PhatVR6 0 Posted February 14, 2004 I've got a 68mm pulley and chip for sale if you're intersted. 1bar = 14.4 PSI. Quote Share this post Link to post Share on other sites
LowG 0 Posted February 14, 2004 just wanted to say that not all g60 have this bleeding off feature, on some american g60 iv heard this feature doesnt exist,i havent done much research on this myself but if you are returning the boost back into the intake pipe and assuming that you have removed the return boost pipe runing a bit extra rich might be a solution for saving you from pinking on high revs. Quote Share this post Link to post Share on other sites
W3RKD 0 Posted February 14, 2004 just wanted to say that not all g60 have this bleeding off feature, on some american g60 iv heard this feature doesnt exist,i havent done much research on this myself but if you are returning the boost back into the intake pipe and assuming that you have removed the return boost pipe runing a bit extra rich might be a solution for saving you from pinking on high revs. why ???? how would this work as if your running a re-route kit how will the ecu know this ??? its the ecu that triggers the isv to bleed. and so there for its the ECU that needs not to bleed the re-route will NOT solve this from happening please read the other thread explaining this to save this thread going off-topic. Quote Share this post Link to post Share on other sites