Herrin811

I thought said filter was for a gas turbine engine?? Needs big air

HOHN

The flow spec that the Donaldson rep gave me was 1000 CFM @ 8" water. 8" water is a restriction of .28896 PSI. Not too bad.

HOHN

The P/N is PCD100028 but it's not yet on the market, supposedly. Donaldson is developing this filter to meet a requirement given to them by a compressor manufacturer (not gas turbine, as I mistakenly thought). A 50hp compressor is still a lot of air.

I posted on TDR an anecdote about how well this filter filters-- I had some 20 miles of off-road on a SUPER dusty road. The entire engine bay was buried, and you could barely make out the letters on the valve cover. LOTS of dust getting stopped, and NONE getting by that I can see. Inlet tube is perfectly clean. Turbo looks perfect. Even when I could POUR the dirt out of the filter inlet, I had no increase in EGT or other negative impact from severe dusting.

I can't believe that an oily gauze filter would have trapped all the dust that this thing did.

pitr

Is this a firm no go due to production costs or is there still a chance the compressor version will be made that we can mod up?

NHDiesel

First, I have to warn that i tend to be "Johhny Skeptical", and do my best to examine info myself. I'm not trying to start a flame war, or tick anyone off, just doing my best to add info and other thoughts.

What I don't see people pointing out, is that bigger isn't always better. True, the filter can flow 1000 cfm, but how much can the turbo take in? Its limited by the inlet diameter, and other than the filtering surface itself, you don't need any tubing larger than the turbo inlet diameter. I haven't measured it, but for the sake of an example, lets say its 4". That means the filter doesn't need a 6" outlet, just a 4". And if you were to fully enclose the filter for a true cold air intake, the tubing running down to the grill area doesn't have to be any larger than 4". Yes, the filter area itself does need to be larger than 4" because the airflow through it would be less because of the filtering media than through an unobstructed equal size opening. But before and after the filtering surface doesn't need to be any larger than 4". A comparison would be to eliminate the filter from the equation, and run a 4" hose from the turbo inlet. You would be at max airflow, and even if you were to add a 10" diameter hose in front of it with a reducer down to 4", you aren't going to flow any more than the 4" turbo inlet.

If someone wanted to do some real testing on filter flow rates, install an air flow meter inside the turbo inlet tube to measure the inlet air speed. Test it with a straight tube with no filter for a base test, then add different filters to the system to see if any affect the airflow rate. If the airflow slows down, then you know the filter is a restriction.

On our trucks, a small airflow increase can't be judged by driver feel. You just won't be able to feel a couple HP increase. You also can't judge it by how loud the turbo whines. Turbo whine is cool, but it doesn't mean you are making more power, you just changed the harmonics. A good comparison would be to attach a 6' length of straight 4" hose to the turbo inlet. Run it to the front of the radiator, and you probably won't hear much, if any, turbo whine. But run it through the firewall and it would drive you nuts. You aren't making more power, just changing what you hear.

Jim

Ph4tty

II tells me to look for a filter that flows 1000 cfm, but there isn't one made for our trucks as far as I can tell. After reading the long AFE vs BHAF thread I looked at AKRam's solution of a radial seal donaldson filter. I started looking though some of Donaldson's filter info and there's a lot of good options that could work. Looking at those has me thinking I should try to fit a longer/narrower filter with a reducer and a shorter peice of tubing.

Any negatives to the shorter tubing if the filter fits??? Will the turbo burn up a paper filter if its too close? Basically it'd be a bigger BHAF in an semi-enclosed housing which could help with heat sheilding.
Here's an example of what I'd like to try- this is $30 on ebay and it flows 1600 cfm. There's lots of different dimension filters like this with high flow, but most aren't that cheap:

trailtoy1993

The 6" to 4" reducer with the hose duct taped inside is not the highest flow option. There is a phenomenon called a "reversion wave" that occurs when flowing air hits a ridge in the outside edge of its flow path. Basically the air reverts backwards off of the ridge and slows the flow of the air column trying to flow through. The perfect induction is a continuously tapering tube, due to the effect of flow speed versus volume through a tube. As the air sqeezes through the neck of BHAF or whatever into the intake tube as long as the transition is smooth the air actually speeds up to fill the area behind the narrower area improving intake velocity and density. Ideally a continuous smooth taper from the 6" outlet of the airfilter to the 4" turbo intake could be found.

BoostdCTD

My new (to me) BHT3B turbo on the way will outflow that, but since you asked;

Turbo_______CFM____Racing HP_____Daily HP
HX35_______600________420________330
HX40_______800________560________440
HX50_______1000_______700________550
HX55_______1050_______735________578
HX60_______1600_______1120_______880
H2E________1000_______700________550
HT3B_______1100_______770________605
HT4B_______1800_______1260_______990
HT60_______1400_______980________770
T66________800________560________440
T76________1350_______945________743
T88______1450-1750__1015-1225___798-963
T91________2000_______1400_______1100
T100_______2600_______1820_______1430
T105_______2900_______2030_______1595
Big Brother__1900_______1330_______1045


KSB1B (KSB1-2) - 400
KSB1 (KSB1-1) - 450
B1B (B1-2) - 425
B1 (B1-1) - 475+

Also it isn't all about how much air it can flow, it is about the ease it can flow it. If the turbo has to make a 12" vacuum to flow 1200cfm versus a 4" vacuum then surely the one that is only 4" is superior.