I know this may have been covered in the forums already, but I couldn't really find the answer through my search so I'm posting the question again.

I have a 2010 Mini Cooper S and am looking to add a bit more power than what I currently have: intake/cat-back. I have heard the downpipe (high flow sport cat - not gutted) may throw a check engine light.

I'm looking at the Milltek Hi Flow Sport Cat. Would this cause overheating and also a CEL?

Thanks in advance.

Denny

 

You shouldn't have to worry about any overheating as long as you keep all the heatshields in place. Check engine light is almost a guarantee.

 

yep, I think OEM is atleast 400Cells maybe 600 or 800 and most HI flow are 200 , not enough cleaning. That's why I just live with it, I'm not swapping out the DP every year for emission testing. I have a can tool and would not see a code but that also gives a not ready emissions state.

 

Not to hijack here or anything but I've been trying to find out the OEM flow rate and this is the closest I've come to someone mentioning it. Like rckrzy1 said, most aftermarkets are 200 cell or less but can anyone confirm what the OEM is rated at?

To answer the OP's questions though, overheating shouldn't be an issue with the heat shields in place as Griz said and CEL is almost guaranteed.