ninoG60 0 Posted December 16, 2006 Hi Just wanted to know if I could possibly pick your brains about 2 matters. The 1st one is , do standard chargers have a steel pulley or did they have Aluminium ones? reason Im asking is that i noticed after removing the belt from my charger that it was an Ali pulley, tried measuring it and it was round the 68mm diameter, but as space was limited, i couldnt tell properly to get an accurate measurement. The 2nd one is the belt number, IF it was a smaller pulley then it would have a smaller belt, the one that was on my car had this number on it 68417. It was a Gates belt. Can anyone let me know if this would suggest that I have a smaller pulley and therefore if it is so, then would this also mean that I would have a chip inside the ECU. Sorry if this is a long post but I just wanted to know as my charger makes about 8 psi and if it has a smaller pulley, this would suggest that it needs a rebuild (Gwerks) Thanks Quote Share this post Link to post Share on other sites
2jesper4 0 Posted December 17, 2006 If its an ali wheel then its an aftermarket thing, the original one i made from steel and is 72mm. So I would get in tuch with G-works if it was me. Best of luck Jesper. Quote Share this post Link to post Share on other sites
Supercharged 2 Posted December 17, 2006 Yeah - thats a 68mm pulley then, it may not have a shorter belt, Jabba used to modify the tensioner... 8Psi is not good and altho it's always a good idea to get the charger checked out if you don't know the history, it could be just a boost leak maybe at the baffle box or one of the plastic intercooler pipes... As above - well worth a trip to Gwerks for a check over and tune up Quote Share this post Link to post Share on other sites
ninoG60 0 Posted December 17, 2006 the tensioner is standard length too! just cant understand it! it does however go very very well so maybe the reading from the boost gauge may be wrong? its tapped into where the pipes go to the carbon canister( which was binned) front of inlet manifold near isv small 8mm(?) pipe that comes out the front.i put a boost gauge pipe to take boost from there. Quote Share this post Link to post Share on other sites
flusted 0 Posted December 18, 2006 mine only shows 12psi with a 65mm pulley. This is because the more breathing mods you make,the less resistance there is to cause pressure. You prob have a cam and flowed head Quote Share this post Link to post Share on other sites
ninoG60 0 Posted December 24, 2006 right , the small belt was changed( thanks to Rob at Gwerks for the speedy delivery) and it gave me chance to take the pulley off. Measured as best as i could and it is an aluminium pulley and measures 70mm from crest to crest on the ribs. I saw a post somewhere that said that a guy had a 70mm pulley with a standard belt, which makes sense to me now as the shorter belt is a different number. The tensioner is the same length too . Soooo does that mean that my car will be chipped too? Just curious as to what the standard pulley size is too. will check for boost leaks as it only shows about 8psi on my gauge, but i suppose the gauge could be wrong. Quote Share this post Link to post Share on other sites
willg60 0 Posted December 24, 2006 Standard pulley is 78mm. You should see up to 11 psi with a standard pulley, so with a 70mm you should be getting somewhere nearer 13 psi. My old G60 ran a 68mm pulley and made approx 14 - 15 psi. I ran it with a 70mm pulley with standard chip for a few days once and other than being a little flat, it still made a big difference to the performance. Ideally you ought to have the thing re-mapped whether it's chipped or not, as chances are it's a plug and play chip which if I remember correctly are normally pretty bad. I think at that time I was using the original belt too before I moved on to a Bahn Brenner extender jobby. I think your guage might be out. Quote Share this post Link to post Share on other sites
ninoG60 0 Posted December 26, 2006 cheers 4 the response guys. Quote Share this post Link to post Share on other sites
Rob_B 0 Posted December 26, 2006 mine only makes 8psi on the guage 2 Quote Share this post Link to post Share on other sites