Supercharger/Boost Question

[bennyx_o]

Quick question for you regarding boost. What does the Cooper S boost to as standard? Had a quick (ok, very quick) look and couldn't find much info on it. It's a pre facelift S if it makes any difference.

Cheers.

[MINIAC]

According to the FAQ boost is 0.8 bar [11.6 psi].

[bennyx_o]

*facepalm*

Thought I saw it somewhere a while ago alright. Confirms my suspicions that theres at least a reduced pulley on the one I got. Boosting to ~15psi at about 5,000rpm

[Richard Crofts]

15psi sounds like a 15% reduced pulley. From what I hear and have seen on many cars the JCW with right aftermarket equipment and the 15% can get around 14-16psi. 17% pulleys tend to boost a little higher and can hit the traction switch off point of 18psi on a nice cold dense day if they have optimised bypass valves etc

[r1_kde]

MY JCW reaches 10psi give or take as an S it reached 8 psi. still got to sort the bypass though

[bennyx_o]

Right, I did some more "testing" today and according to the Boost gauge it slowly creeps up to ~15psi, but it's at about 5.5-6k RPM. I'm going to go out tonight and measure the pulley if I can find it, IIRC the standard pulley is 65mm?

[R56]

I have a -15% pulley on my MCS and have seen nearly 19.5 psi boost on the gauge,even in ermmmm normal driving 15 to 17psi is normal,the little bugga really flies

[bennyx_o]

Not too sure what I get normal driving, the guage is down under the toggle switches so it's not something I like to look at when driving around town.

It certainly feels faster than the other S I drove, mind you It was over a year ago when I drove it. Both the same, both pre-face-lift. Friend of mine drove it on Saturday and said it's quicker than his friends which he drove earlier. I'm not too concerned if it has one or not, but it's something I can knock off the to-do list if it does.