A technician I know has suggested that there MUST be a way to modify the stock CAI box and exhaust on my 05 MCS to improve performance without spending the exhorbitent amounts for aftermarket products. When inspecting the car he said that the stock exhaust system seems inefficient and the shop could install one muffler and some nice tips decreasing resistance and back pressure for MUCH less than buying a Milltek or Borla.. He also wondered if anyone here has done a simple mod to the stock CAI box and if so, what it was. He's an honest guy and I have to admit that paying over $200 for a piece of stainless and larger filter seems like a rip off to me, as does the pricey exhaust systems.. I'm not cheap, but I also don't want to throw money down the toilet.. Any feedback folks?

 

You can get either a stock replacement foam air filter or a higher flow panel filter to go in the stock air box.

The "one ball" exhaust mod is pretty popular and there are many threads on here about it.

 

Seems like it COULD be a good deal. Some shops will do a 1 ball exhaust for $50-$75 a filter will not cost too much. If there are other shops then call them and get other prices. If you don't want to spend the time calling and doing homework then this is the way to go.

 

OK.. so I guess a K&N filter for the CAI box then? Not sure what the "one ball" exhaust mod is though.. Any chance you guys can explain so I know what to tell the exhaust shop? When I called there today, he basically said doing a custom modification would be more than the Magnaflow or Borla.. However, I was reading about the Volt system, http://www.detroittuned.com/products...20070701203913 which looks and sounds great though it says it was engineered for an 02-03. .I can't imagine it taking much to customize for an 05 since they're all R53's. I was hoping to spend even less than this, but it might be a good solution.. Let me know about the "one ball".. Thanks again!

 

Your best tool for the job is not even the phone it's the search tool button on this forum. All your questions will be anwsered if you only type: One ball mod

 

There's also the swiss cheese mod to the stock filter box...

 

Thanks much guys.. VERY helpful.. I printed out the photos/diagram from one of the threads and can now take it to a muffler shop.. I think it would be sweet to change the exhaust tips, though the OEM Gen 1 round tips to replace the beer cans are $100.. major rip off! Any suggestions there? And would it be fair to assume that most dealers (I go to Mini of SF) will make a fuss over the one ball? Will they also make it over the swiss cheese mod? Just wondering since I have 2 more years of warranty.. Thanks again.

 

Well just ran the search on the swiss cheese mod and there really isn't much.. Mostly there are threads from guys who built their own CAI (HAI??) or modified an Alta or other CAI.. Any other suggestions on how to search for this? Thanks again.. it's not easy being a newbie.. DOH!

 

Hey there fellow newbie,

the swiss cheese is basically drilling a formation of holes into either the stock airbox (top, bottom,or both) and the backing panel behind the airbox in order to take advantage of the airflow coming in from the vents just under the windshield. This can be done one of two ways; either using a dremel tool and drilling many little holes (hence the "swiss cheese" reference), or simply cutting out a large area. I did the latter and it made quite a difference. Easy to do, takes a bit of time but well worth it. Also, Mini Madness sells the backing panel with an enlarged precut hole for $40. but if you have a drill, a wrench, a screwdriver and a couple of hours... you'll save the cash.

 

I'm looking to sell my ALTA cai with the lid and like new filter. To buy this it would cost about $250, I'm looking to get $150. Not's not much for 10hp. Let me know if you're interested.

 

Do a search on HAI. It's basically a K&N filter strapped directly to your TB. I've tried this setup - it works great! Echoing what everyone else has said, the one ball mod is the way to go to save $$. I've you're willing to drop a few more bones, the Volt catback looks promising.

 

Jay, do you still have the intake for sale, and if so would it fit on my 02 MCS ?

 

Here's my thread about "honeycombing" (or swiss cheesing) the stock airbox:
https://www.northamericanmotoring.co...ight=honeycomb

 

I tried a few filters in the stock box and settled on a foam Unifilter (looks just like the Alta filter). It's in the stock box, which seems to resist heat pretty well. I had an aluminum box with heat shielding around it, and it was WAY too hot, even inside the box.

Ken