Right now i have an open air filter on my truck. Do you think this could be hurting performance cause it might be sucking in hot-air? I like the JLP intake and thiking about getting one. Also, i have the R.E.M. intake tube and some say the JLP kit wont fit with the REM tube inless i have a cowl hood. Anybody hear anything about this as well?

 

I personally don't believe you gain anything from them. Maybe you do when you make big HP, but not for the average Joe.

You need to run them at the track side by side to see. I saw a consistent 0.15-0.2 better ET with stock box w/K&N over my open airkit on my old truck. That was a sealed airbox. On my 03, I am running a modded, non-ramair box.



I see 15# with this box and my Apten + 4# lower. So it seems to be working great thus far

 

A closed box, like the JLP ramair will feed the engine cooler air. We have checked this with the Predator on three trucks. JLP: IAT 1 was same as outside air when moving. The open filter trucks were 15 to 20 degrees higher.

 

I lost 8hp when I switched to an open air filter on the dyno. My truck is mostly stock - stock pulleys, exhaust. I have a ported Eaton and a modified stock airbox with a K&N panel filter.

1st pull - 368hp - modified stock airbox
2nd pull - 360hp - REM Power Tube and 12" open air cone filter
3rd pull - 369hp - modified stock airbox

Like other have said, unless you are running alot more boost than stock, I don't think an open air filter helps at all - in my case it hurt.

 

Yeah, I would tend to agree that at stock boost, the factory air box works fine.

Above 12psi boost, I think cone filters start to help a lot. Especially ones that have a filter on the end like the AirForce 1 to pull cold air from the fender area.