First off I have two ‘05 R53 Minis, one is for work and the other is a low mileage jewel. So today I changed the oil in the jewel and after I finished I took it for a drive. Only mods for this one is a Miltek Exhaust a CAI and a 16% pulley. For some reason this car pulls hard and gets 18# of boost. Well today I stayed in the throttle to redline and hit 20# of boost on the gauge then acted like someone turned it off and smelled rubber big time. Check engine light came on with the two bottom lights in the main cluster and would not rev over 1800 rpm and limped it home at 12 mph. Put the scanner on it and came up with Cruise and throttle body something. I figured it slipped a belt but was still there. I cleared the codes and took it for another drive. Runs the same but can’t get over 10# of boost and can hear a squeal hear and there. I just removed the belt and looks fine do I don’t know what happened?? Please help.

 

Sounds like your crank pulley gave out. Very typical on these cars. The rubber dry rots, and causes the pulley to separate the two halves

 

+1

See this thread and check out the video for diy replacement, including footage of the pulley separating in two pieces at 6:50.

https://www.northamericanmotoring.co...ing-maybe.html

 

oh I didn’t think about that yeah I bet that’s it. Thank you!!

 

+1 on the crank pulley. Do yourself a favor and replace with a fluid filled unit, either PRW or ATI. It's a much better part and should provide a smoother idle.

 

Yep that was it.

 

I have a 2% ATI on my other one and will buy another one but whether to keep it stock or go 2% as well??

 

I would of you don't plan to track it. Otherwise you will probably need a little extra too cool it down on high RPM

 

yes true as I have a Airtek 60 mm on my daily. Yeah I’ll just keep it stock.

 

A “Stock” ATI is actually about .8% bigger due to the minimum size of their damper assembly/core if that makes any difference in your decision.

Either way, an ATI is a solid choice for a crank pulley.

 

well on my daily driver I have the 2% od and have charging issues around 6k rpm and don’t want the same thing.

 

thanks so it’s actually .8% overdriven?

 

Yes, according to post #22 in this thread, and by using the diameters from the ATI website in calculations.

https://www.northamericanmotoring.co...ml#post3468157


What charging issues are you having? I have a 2% waiting for install and now I’m curious if it will cause a problem.

 

Well it’s not supposed to do this but for my car when I get above 5k rpm I loose all gauges but will come back as soon as I’m under that. It varies anywhere from 5-6000 rpm. I hate it!! So I think the voltage regulator can’t handle it so I had my non oem alternator rebuild by a local company and took care of the problem but in return has my power steering pump running non stop??weird! So I bought a reman from Advanced and took care of the power steering issue but back again everything shuts down around those rpms I mentioned.

 

Dang, you make 18lb of boost ? My setup with my 17% only makes 15lb

 

Like I posted I have two ‘05 R53s and this car pulls extremely hard for some reason where as my daily R53 has many mods much more and more aggressive than this one and average 16#s of boost unless it’s cool or cold then I can hit 18#s.