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Hi all I have ad 2003 cooper s with 110k miles, got a 15 percent pulley Alta intake and a Detroit tuned bypass valve. From what I have seen and read I should be getting roughly 15psi of boost at WOT. I am at altitude so a tad less would be expected. However I am only seeing on my ultra gauge and a quick data logging app that I am only seeing around 9.28 - 10.2 psi of boost max. I did not have ultra gauge till after pulley install so boost with OEM pulley is unknown. The belt is new, tensioner is new, bypass valve is new, supercharger was serviced roughly 10k miles ago has new boots and a brand new black intake tube and green gasket not that that would matter but just throwing it in there. Have already tested for vacuum leaks using soapy water and brake cleaner, no leaks at all. Also no codes car runs great idles great. Any ideas what is leaking or wrong.
As reported in my (sig) thread topic recently, I too have what I suspect is a 15% pulley. My buddy and I did prox 125 miles roundtrip mountain run from town base at 5k' elev to prox 7.5k' elev at which point we turned back home. During the 2nd leg, my buddy drove and I took a few pics of various "virtual" gauges displayed from OBDLink MX+ dongle and tablet dashboard display. Didn't do any wide open full throttle runs but close to that just briefly uphill while I drove where we saw ~ 10 psi max boost. At what elevation(s) did you record those readings? I too would like to validate what I saw vs what I think I should have seen, i.e., related to elevation or lack of correlation with displayed values to what amount of boost was actually being produced.
As reported in my (sig) thread topic recently, I too have what I suspect is a 15% pulley. My buddy and I did prox 125 miles roundtrip mountain run from town base at 5k' elev to prox 7.5k' elev at which point we turned back home. During the 2nd leg, my buddy drove and I took a few pics of various "virtual" gauges displayed from OBDLink MX+ dongle and tablet dashboard display. Didn't do any wide open full throttle runs but close to that just briefly uphill while I drove where we saw ~ 10 psi max boost. At what elevation(s) did you record those readings? I too would like to validate what I saw vs what I think I should have seen, i.e., related to elevation or lack of correlation with displayed values to what amount of boost was actually being produced.
So these were taken at around 5000 feet so fairly high for sure.
At the point I was "on the boost", we were north of Pine/Strawberry driving uphill nearing 6500' elev. Other times at moderate throttle bursts not near wide open throttle, we saw ~ 2-6 psi...
At the point I was "on the boost", we were north of Pine/Strawberry driving uphill nearing 6500' elev. Other times at moderate throttle bursts not near wide open throttle, we saw ~ 2-6 psi...
I think I have something similar as well. I was thinking it might be the map sensor on the intake manifold being dirty or being bad. Considering I have fairly low mileage and no boost/vacuum leaks that I am aware of. How many miles do you have at the moment?
Oh I completely did not realize you are the dude who bought that stunning low mileage mini. Gorgeous car by the way, I would hope no parts are worn out yet but it is a 16 year old car that I assume has sat for a while. I'm no professional tech at all but I am stumped. Why does everything have to be so hard with these cars.
Update. Did some more vacuum leak testing and still found nothing. I also replaced the MAP sensor on the intake manifold and still nothing has changed. I did recently learn though that peak boost should come on at about 4800 to 5200 rpm. My peak boost is coming on at redline. Any more ideas?
