I am thinking about getting a CAI to increase gas mileage and HP for my xA. I will be doing almost exclusively highway driving, if that makes a difference.

The question I have is do I also need to upgrade my exhaust if I get a CAI? or can I use the stock muffler? What benefits would a bigger muffler pipe give me with the CAI?


Sorry if this is the wrong forum.

 

You don't need to upgrade your muffler, no. It won't damage it or anything if that's what you're thinking.

To fully upgrade your car's ability to breathe though, yeah, you need to upgrade your exhaust system (headers and cat-back or axle-back).

I noticed a difference even after just doing a SRI though. My MPG went up and was more responsive at higher RPMs.

 

What short-ram intake are you using, cid_mcdp? I'm looking for an intake and was just curious since you seem to have good results with whatever intake you have.

Thanks!

 

Thats a yes & no kind of thing. You dont need to, but by even getting a precissionmuffler.com axel back exhaust, you would gain a little more milage. Most would say this is wrong in logic as More Air In + More Air Out = More fuel needed. Yes that makes sense, but the engine can become more efficient at some RPMs because of this, & in fact would use a little less gas because it would not need to work as hard to maintain the speed. As for short ram vs CAI, not much of a diff. Both would probably show the same gains when it came to mpg added.