Just curious what you think about an overdrive crank pulley 2% with the 15% under drive SC Pulley? Will this damage the alternator or electrical system? Also, I don't see any procedure for replacing the timing chain, guide rail, tension rail and tensioner. Is this something good to do since I have my Mini S in pieces right now? 2002 Mini S R53. Thanks. Can't wait to get your book for my Boxster!

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This post was auto-generated based upon a question asked on our tech article page here:

I personally wouldn't mix two under-drive pulleys. I'd pick one and stick with it.

If you have the engine apart, it's not a bad idea to replace the timing chain componenets. However we do not currently have a tech article for that procedure. You could grab a repair manual, it would be in it. Give our parts specialists a call, they will help you find the right manual and parts.

- Nick