Engine/Transmission (1998.5 - 2002) Request input on air filter experiment.

[CumminsFarmer]

Hey guys,



Im still running a stock airbox on my ought 2. I have two friends (one with 99 24v, and one with 97 12v) that are running a straight cylindrical tractor air filter, with no box whatsoever. I apologize because I dont have part numbers. Its fairly simple to picture though. They simply removed the air box, and hooked the intake tube directly onto the end of the cylindrical filter. Neither has built a heat shield or anything, and just lays the filter on the fender where the oem box was. Im considering installing one, but will build a heat shield. Could anything bad possibly come of that? Thanks.

 

[JOdell]

The filter you are most likely talking about it the Big Honkin' Air Filter (BHAF) This a very common filter used in the diesel world. What it does basically is let your turbo suck in more air. Other guys (me included) use the AMSOIL 4510 Nano fiber filter. Same princable as the BHAF but get more air to the turbo and is cleanable and is not a oiled style filter like the K & N style filters. Here is a picture of the BHAF & the AMSOIL 4510 filter side by side. -Jason

 

[rweis]

Right off the bat I can think of about 4 to 6 "manufacturers" of air filter systems. Some are oiled, some are washable, some are dry. I use an oiled, but purchase a new one every year and do not mess with the oiling.



There are several threads of heat shields. Do a search, some are "TDR member basement enterprise" and are generally very well made.



I use a Scotty II (not even obtainable anymore). Its selling point was it drew outside air, not air from under the hood. I cut the cowl hole, and it is a little noisy (turbine whine), but I (myself) like it.



Some of the newer air boxes get their air from only the fender oval and try to minimize the under hood air.



Some drill large (2") holes in the OEM box under the filter for more air.



If you are under 350 hp, you probably do not need any of this. Just make SURE (SURE) your filter is air tight (stock OEM box is iffy on the air tightness unless you do something to make sure it has a GOOD seal (filter) to the box)



Lots of possibilities,



Bob Weis

 

[Forrest Nearing]

Bob, I'll buy your old filters

 

[Joseph Donnelly]

Airflow of different filters and horsepower on the Dynojet dynamometer were discussed in TDR #37, p. 26. If your engine is below 500 horsepower, you probably won’t notice a gain in power or reduction in egt from a non-stock filter system, unless it draws in cool air instead of warm underhood air.







Air filter—brand, part number Flow in cfm @ 6” water restriction Dynojet measured horsepower

Fleetguard AF25541 in Dodge air box NM 549

Fleetguard 25090 550 NM

Fleetguard AF1752M in steel air box 812 558

Fleetguard AF1752M No air box 812 570

Donaldson B105006 (BHAF) NM 568

No air filter, box, or hose on turbo 1050 570

Fleetguard AH19037 (BHAF) 687 NM

AFE 60-90037 filter and 50-10071 housing 820@1. 5" 574

Fleetguard AH19002 fiberglass media 470 NM

K&N RE880 on Dodge hose 1400@10" 569