I was reading Alta's site about their CAI system that shows a 10 HP gain. My question is how does this compare to the JCW intake? I have not seen any numbers referring to the increase gained from the JCW intake over stock.

Just trying to decide which route to take.

 

There isn't HP in intakes on an R56. If there is any gains in intakes it's like 3hp or less which is hard to dyno prove. Don't buy an intake trying to get power, buy it for the sound.

 

Stock JCW and MCS air boxes are the same from the factory. The JCW stage one is said to flow more air though.
The Alta is a different design all together. The advertise 10hp, I lost about 15mph from my top speed running the Alta. It sounded great but didn't help me at all. I put the stock box back in and got my 15mph back.

If you plan on getting a tune, Jan at RMW has stated the stock box will make more power than the CAI.

 

Thanks guys - that is EXACTLY the info I needed.

Way, were you able to get that stock lower air box bottom out yet?

 

I have a new JCW and was thinking about intake. I would like more sound.
I heard just K&N drop in will flow more air and give some sound. I like the look of the DOS and the reports are good. The ALTA system I like because you ipen up the scoop which should cool the engine compartment some. I live in rainy Seattle so I have fear of water getting under the hood etc. The DOS is kind of cool because you can quite it down. Is there a good way to get more sound with a stock JCW Box. I do not think just a K&N drop in would give me the sound I am looking for. Thoughts?

 

I put the K&N drop-in and there was very very very little change in sound if any.

 

The stock S intake is a cold air intake. It draws air through a duct that takes suction from the front of the car, behind the left side of the grill. I'm thinking that a foam drop in air filter in the stock location, and maybe a larger diameter intake duct would give you more cold air than you could use.

Dave