Originally Posted by Hobbymanbill
A look under the hood of ANY production street vehicle. NOT ONE comes with a K&N filter. Over the years many products have been adopted by OEM's, but ONLY those that work.
Hobbyman, I have to agree with you when you say don't expect much more than 2% increase with a "smooth" vs the "accordion" style intake tubes that our XFs came with. But I think the Viper is still considered a "production" street vehicle, albeit, a "limited production" street vehicle, and it's been offered with K&Ns since 1998. 1st. on the GTS-R, then in '99 on the ACR versions. I think they're standard on all the new Vipers since 2003.
In '98-'99 Dodge claimed it added 10 hp, but that's on top of the standard Vipers 450 hp which made it about as close to 2% as you're going to get. Personally, I think most of the increase came from the "smooth" intake tube that automatically comes along with the K&N "package"...Mike