vw_john 10 Posted August 28, 2012 What boost are you guys seeing at 4,000 - 4,500 RPM? Im curious as im sure mine is far too low! Cheers Quote Share this post Link to post Share on other sites
owen g60 10 Posted August 28, 2012 With a really heavily ported charger and 65mm pulley I see 14psi. Near the limiter which is now at 7500 I saw 23 psi on Sunday night!!! Quote Share this post Link to post Share on other sites
vw_john 10 Posted August 28, 2012 Bother, I am only getting .5bar which is 7.25psi and right before the limiter im getting .9 bar which is 13psi this is on a recently refurbed charger at stage4 had the system leak checked to find nothing, this is really bothering me now! Cheers for your response though and im happy for you getting 23! Quote Share this post Link to post Share on other sites
owen g60 10 Posted August 28, 2012 All depends on your pulley size. My charger was a jabba stage 4 but I ported it more when I did the rebuild. I was seeing similar figures with a 68mm pulley before my rebuild. Are you still running the boost return? Does your isv vent to atmosphere or back to the intake path? Quote Share this post Link to post Share on other sites
JMC 0 Posted August 28, 2012 Very dependant on engine setup mate. I run a 65mm pulley, and never get more that 12psi even with a freshly built charger and wide open throttle. Extensive headwork on mine means the pressure never really builds - it just flows efficiently. Quote Share this post Link to post Share on other sites
vw_john 10 Posted August 28, 2012 Well its running a 68mm pulley and the boost return delete, the other side of the charger is connected to the rocker cover? Its never had any headwork done so i'm a bit annoyed its running so low/slow, the car was dynoed at 160 at the fly before i got it, and that was on the 68mm pulley before the porting, but its never felt any faster after that. Quote Share this post Link to post Share on other sites
owen g60 10 Posted August 28, 2012 Does your isv vent to atmosphere or back to the throttle body?? If it goes to atmosphere you won't see higher than 14/15 psi as that is its leaking point Quote Share this post Link to post Share on other sites
Yandards 0 Posted August 28, 2012 Does your isv vent to atmosphere or back to the throttle body?? If it goes to atmosphere you won't see higher than 14/15 psi as that is its leaking point It's not leaking its designed to do that. The ECU starts to bleed boost air back to the return side from around 5k to enable a smoother cut in for the rev limiter to prevent damage to the charger. As I have said many times before and JMC has touched on, high boost does not necessarily equal good performance, a tweaked head will reduce boost through more effiecient flow and different boost pipework and an intercooler will also have a similar impact. Performance is all about CFM or airflow through an engine, upping the boost pressure is one way of achieving this but it is a little crude. Quote Share this post Link to post Share on other sites
Rustynuts 0 Posted August 30, 2012 How does it drive, does it feel as if it is down on power? Quote Share this post Link to post Share on other sites
vw_john 10 Posted August 31, 2012 i have a non return valve on the ISV but It only goes up to .9bar on redline, and if im honest it does feel low on power ad my mates polo gt (1.3 8v) sticks with it until i beat it in the higer revs, which upsets me. I did purchase a g-lader from ebay but the oil lines were shredded so i couldn't test it out. still looking for another to try! Quote Share this post Link to post Share on other sites
owen g60 10 Posted August 31, 2012 (edited) Get the oip ports re threaded... i took mine to a local engineering place after someone had put the wrong banjo bolts in it and stripped them. cost me £10 for 2 heli-coils to be fitted to it Thinking about it... if youre still not making as much boost as you think you should be on a relatively new rebuilt charger, maybe the internals are starting to show their age. some places use a really hard compound strip on the scrolls when building, this can wear the metal very quickly instead of the apex strip wearing... Just a thought hope its not as thats a complete replacement job Edited August 31, 2012 by owen g60 Quote Share this post Link to post Share on other sites
vw_john 10 Posted August 31, 2012 well, there was talk of retapping, and using heli-coils, but considering i baught a 'fully working charger' and it wasn't I thought it would be best to return it. however im now getting greif from the seller, hah. When i get my money back, i'll purchase another and see if the boost changes. cheers guys Quote Share this post Link to post Share on other sites
G60 CS 0 Posted August 31, 2012 I have a standard charger rebuilt by BBM i bought as part of a 16vG60 kit I imported, its only done 600 miles, I now have a Jabba stage 4 and a Lysholm so if youre looking for a charger ................... Quote Share this post Link to post Share on other sites
vw_john 10 Posted September 2, 2012 ... are you selling the lysholm? Quote Share this post Link to post Share on other sites
G60 CS 0 Posted September 18, 2012 ... are you selling the lysholm? No the Lysholms not for sale but I do have a standard charger that was part of a BBM 16VG60 kit I imported from BBM i used it for the first 600 miles running in my new engine then switched to my Jabba stage 4, The Lysholms for my MK1 G60 conversion Quote Share this post Link to post Share on other sites
DanVW 0 Posted September 22, 2012 If you have checked for leaks in the boost pipework and not found anything I would be looking at checking and then double checking the timing, it can make a huge difference on the G60 if it's even slightly out. Dan Quote Share this post Link to post Share on other sites
