What difference did you guys notice when you put on the BHAF? Truck is stock except what's in my sig.Thanks.

Turbo whistle was louder.

* Filter last up to 135K miles* Turbo sound is louder* Turbo and air system stay clean

No MPG increase? Not till I do something with the exhaust too, I suppose.

No MPG increase? Not till I do something with the exhaust too, I suppose.

Exhaust change not required. I'm still running 3" pipe. Remember the only time exhaust upgrades are needed for reducing EGT's and increasing flow is when your WOT going down a 1/4 mile strip. If your driving with economy in mind then there is very little boost and very little EGT's anyways so increasing exhaust is not going to change MPG's. There is a lot of market hype for large exhaust and intake tubes. But for MPG mode its not needed. But now if your doing quarter mile or dyno queens then yes it would be best for a upgrade.

Thanks Mopar. Mostly the truck carries the camper. So I drive very easy. Once in awhile it gets a short errand run empty. I worry about it sitting most of the time. I do remember to start it each week.

BHAF pleated paper surrounded by metal mesh. Prevents mice damaging filter.

An "Outerwears" filter cover is nice. It filters down to 5 microns. You can get it water resistant. It's already heat resistant. It's especially good to cover paper filters. I noticed more low end torque. I added a Banks twin ram and that made another difference in the mid range that was noticeable.

I put one on my truck because It had a K&N gauze one on it when I bought the truck and I know of a few people who have had issues with the filter coming apart and tearing up the turbo. As big as the filter is I don't think you will ever exceed the amount of air flow that it can provide.

i noticed slightly faster/easier spoolup as its not working hard to suck air through a small filter...because it has so much more surface area the suction has less pull on debris and the filter is much cleaner.

There is enough reason to get mine installed and quit letting it sit on the workbench. Yeah I'm a lazy ole' dog on weekendsThanks everyone. BTW I have the outerwear cover for it. Vulcan performance is cool honest folks to do biz with.

Made more noise, basically turbo whistle was louder.My 4 inch exhaust made it louder again, did nothing for mileage but did run cooler when towing heavy. Changed to a Scotty Air and made it quieter and did lower EGT's a bit when pulling the same heavy loads.Best thing I ever did was drive it like a human being and keep the revs under 2000 rpm, mileage gains prove it.Jeff

Made more noise, basically turbo whistle was louder. My 4 inch exhaust made it louder again, did nothing for mileage but did run cooler when towing heavy. Changed to a Scotty Air and made it quieter and did lower EGT's a bit when pulling the same heavy loads. Best thing I ever did was drive it like a human being and keep the revs under 2000 rpm, mileage gains prove it. Jeff

Thank you Jeff and all others too, for the information.

i would highly recommend the outerwears filter cover, very easy to clean and saves you from replacing the filter

i would highly recommend the outerwears filter cover, very easy to clean and saves you from replacing the filter

Yes I did get the outerwear cover when Eric at Vulcan performance recommended it . Still it's sitting on my workbench not installed. Just doing my winter hybernation (rest) for now. Actually lazy..... that is the word

I didn't waste my money on an outerwares... not that they aren't nice but the BHAF has a wire mesh to keep the mice from damaging it. The same mice that trashed all my under hood insulation... would destroy it.

I'm with Russ. Save the money to another filter when required. They look nice but mine started to die long before I. Would have gotten through the filter

I'm not going to bother with an outerwear when I get a BHAF. Waste of money IMO. . .

I'm not going to bother with an outerwear when I get a BHAF. Waste of money IMO. . .

I wouldn't go that far... But I will admit that washing them are a pain in the butt and then trying to protect them from rubbing holes in them another pain in the butt.

It's a BHAF thread, but there is a little discussion on exhaust. Let's look at a few things. While most of use don't run at full power most the time, the engine needs to have all of it's components sized correctly. A HX35 is capable of flowing about 800 CFM, which at 1200° is 2000 CFM of exhaust. That is barely going to flow thru a 4" exhaust with acceptable back-pressure, let alone a 3" exhaust. Specs from Cummins put the QSB 480 turning 3400 rpms at 932 CFM of intake and 2174 CFM of exhaust at a manifold temp of 1301° and 35 psi of boost (boost isn't as relative as CFM as we don't know the cam profile). RPMs aren't relative either, its an equation of intake CFM and exhaust temp. There truly are very few applications where a 3" exhaust is acceptable on a ISB over 250 hp. The 3" exhaust was barely enough on a stock 02 HO, with any sort of mods a 4" is needed. Guys will put 4" intake tubes on their air filters, and leave a 3" exhaust. The exhaust flow is roughly 2.5x that of the intake at 1200°.

Makes a lot of sense to me