Sorry guys I hate when topic titles are generic like that just to lead you in to read but couldnt really think of a concise titles.

Anyway I have an AFE intake and it is an "open" design where closing hte hood effectively seals the top of the new airbox. Well my rubber stripping that was around the heatshield/box ripped the other week and for the past few weeks It has been without this and I didnt think it made a big diff considering the hood will still cover the thing but maybe not create a true seal

BUT after waiting weeks to get a new part-they messed up the first time and low and behold today I got TWO of them-anyway I put the rubber seal stripping on and go for a ride and WOW-I am not naive and not gonna say I got 10 hp or something but I DEFINETLY noticed a difference. I mean I cannot see why this would happen unless I was thinking without a sealed airbox would air be "escaping" out the box and into the rest of the engine bay instead of getting funneled into the intake pipes?

I have no clue if this could affect performance but sound also improved. I really think it was not sealing and not creating that closed space to give it the true sound and performance.

By the way if anyone needs an AFE rubber stripping piece for their intake let me know and its yours!

 

Ya I think the vacuum it creates and tunneling the air into the intake at only one place is more effective.

It also could be that hotter air is getting into the intake so you get less air... hence less A/F ratio mixture so less power.