I have recently installed a M7 16% super. pulley. Now the question, does this change the boost? or simply add more air to the system Also, what is the boost psi. on a 03 MCS. Thanks for the info.

 

Stock boost is about 10.5psi and now you are about 16psi. More boost equals more power plus the boost comes on quicker. You really should get a cold air intake, it helps with throttle responce, hp and makes a cool sound. I have an Alta with the silcon hose.

 

It spins the S/C faster, which increases the air pressure (boost) and gives you more air, however it raises the temp which is why we have intercoolers (or if you prefer "aftercooler") any why high reduction % pulleys bring temp concerns. I'm a little mixed up on the #s now, but I'm sure someone will be alnog withthe answer to that shortly.


(You may find you get better answers with a more detailed title as well)

 

The stock IC will handle the 16% pulley fine unless you track the car and even then it won't be that bad. If it's a street driven car you're probably on boost less, well serious boost anyway, than 10% of the time.

Mario's figures are a good baseline for what your real boost will be.

 

couldnt he loose power if he tracked the car from too much heat? :impatient

 

Road course he probably won't loose any noticeable power (@16%) as he is constantly moving, at a drag strip beteen runs MINIs suffer from heat soak, even witht he bonnet open, Not-So-Red has a great how-to of an inexpensive and effective mod to help. It is also the reaosn some vendors have sprayers of aftermarket ICs to help cool things down. A larger IC will increase density and result in some boost loss, however if it can cool it enough, then the lost power from slightly lower boost can actually be more powerful if the air is cold enough.

A 16% isn't enough to cause any real heat worries. but there is a reason that 17, 19 and addtion of crank oulleys to those #'s are not reccomended for track use, as a constant high heat on boost situations they can get the oil too hot.

 

perhaps a bag of ice ontop of the IC inbetween runs would solve it?

 

Yes it will, as long as the hood is open & the ice is removed seconds before the next run. It doesn't take long for the stored heat catch up with the IC.