Afe restricts flow and robs HP, the 6637 or tymar intake systems preform better by roughly 10hp.

Gene, when I stated open element filter I meant to say, open intake(no filter)

Cowboy Steve

 

I was quite willing to let this sleeping dog lie, but you had to go kick it and wake it up again! If only you hadn't called me out by name throughout your post, the poor dog could still be napping peacefully. Now I've got to explain all over again why I think an open element filter that draws in relatively still air from under the hood makes a turbo more prone to developing a vortex. The same reasons apply to any under the hood filter, including the K&N cone that I towed with for several years before it finished off my poor turbo.

BTW, I never said that a 6637 is too restrictive. I quoted CFM ratings from the WIX web site, and I mentioned that they didn't give any restriction data. If you look at my chart which is based on the data from the DONALDSON site, the red 6637 curve is slightly above that for the AIS, but this might reverse as soon as the filters start collecting some dirt.

Whether a vortex was a contributor or not when I towed with my K&N cone remains to be determined, but the type of surge I'm all too familiar with occurred when towing a constant grade at about a 75% power setting. I could find a specific range of throttle settings that if held long enough would produce the rattling noise, clunk, clunk, clunk, type of surge that's most damaging to the turbo bearing. My main point here is that it took a very specific, steady state condition to illicit a surge.

Here's my THEORY to possibly explain my above observations. I'm using this analogy again mainly to save typing out a lot of words involving air molecules, air flow patterns at the compressor wheel, etc... In order for a vortex to form in a sink drain, still (relatively undisturbed) water is required on the surface above the drain. If you've ever watched a vortex form, it requires drawing water into the drain in a symmetrical manner around the entire circumference of the inlet. If a vortex does form, and you ripple the water surface with your finger tips, you destroy the vortex, and the water begins to flow down the drain in a more conventional manner.

Compared with the direct RAM air flowing through an air box inlet, the air in the vicinity of an under the hood intake is relatively still because it's confined to the region of the firewall and fender wall. This allows the air to be drawn into the inlet in a symmetrical manner, with an approximately equal flow around the entire circumference of the inlet. This drawing in of still air in asymmetrical manner is a prerequisite for forming a vortex. This doesn't prove that a vortex will form, but it's a necessary condition for one to form. An air box with a RAM air inlet eliminates this necessary condition. I'm not claiming an air box eliminates surge, but only that it eliminates (or at least drastically reduces) the possibility of forming a vortex.

 

 

^...................BWHAHAHAHAHAHAHAHAHAHAHAHAHA

Cowboy Steve

 

DANG IT!! I want a pic of *MY* truck on a dyno!!! -SIGH- Some day...

BTW, the industrial fan is probably a pretty fair simulation of wind just after first starting off. Nice touch...

 

LOL at Kris

 

LOL!!!!!!!!!!!!!!!!!!! Ah Hell Kris! I needed that laugh!

 

Filters debates =
7
everytime...

 

deleted post

 

I'm responding to this in a separate post because they're no technical issues that I can counter here, except to say that this seems to be boarding on a personal attack by suggesting I've been using "fuzzy math" and "theories that make no sense" to manipulate my calculations for some particular reason, which you don't bother to mention. I don't know who you've seen hopping on my "bandwagon", but there's still plenty of room on it, so I won't have to worry about getting a larger one anytime soon.

I guess all I can say is that if anyone finds a mistake with any of my calculations, please call them to my attention ASAP, and I'll review your concerns, and correct my work as is necessary. As Clux can testify to, in the past I immediately posted a bold faced banner retraction after I finally figured out he was correct and I was in error. The retraction was issued this way to try and make sure that anyone who had read my argument and looked at my calculations, and had gone away thinking them to be correct, would have the best chance of getting the information that was actually correct.

BTW, my retraction would make interesting reading on this thread, because it had to do with the 7.3L AIS element. I would've put a link to it here, but for some reason FTE limits me to only being able to see my previous 500 posts. Evidently, anything you post longer ago than that is gone forever. This is probably a good thing because I can't count the number of times I've seen incorrect information posted in this forum, but I can count on one hand (maybe two) the number of times I've seen a retraction.

 

Gene, if you want to see a post that you written thats past your 500post search limit, type your name into the search box, and type in the Title of the post. It will show your posts only that have what you wrote in it.

 

Tony Hunter (Fred Astaire) is a film star who's way past his prime. He decides to return to the place where his career began.

Sorry guys I couldn't resist. This thread has worn its self out.

 

Actually I wasn't attacking you with that statement, I was making fun of a few others with jumping on the bandwagon because of fuzzy math. Seems that some consider real world trials and experience with the 6637 filter as utterly useless and nonsense babble.

But, I did mention particular calculations and theories of yours that I considered completely off target but you never responded. One in particular off the top of my head without looking at the 11+ pages is your idea of water and the 6637, and how you would be concerned about using the filter even at something like 50% humidity.

 

Gene, without quoting some of your above post.... if I still have my Zoo-Dad, stock ram air tube, and then my 6637, doesn't that mean my filter is recieving more than stagnant underhood air? I mean it is flowing from the zoodad hole through the engine compartment and I assume down and out under the truck right?

 

Ok, there's some factual and technical issues here that I can refute, and I'll be happy to do so. I'll take the "valiant effort" as a compliment, but it's really just a hobby of mine. The wife does crossword puzzles to help keep her brain alive, and I do calculations. I calculate anything and everything, just for the pure enjoyment of it all, and sometimes I wind up getting some interesting results that I share with others. BTW, sometimes I get interesting results that I decide not to share, mainly because it'd be too much hassle for me to handle all the negative response. Case in point, the top 5 reasons why exhaust stacks rob performance! You can bet that I'll be keeping that analysis to myself! The only reason I mentioned it now was because mech's pic reminded me of it.

Lets talk about "Like the other calculation at the beginning of the thread with humidity and the air intake." You should've seen the complete set of these calculations, and the resulting debate concerning them, because you posted several times here https://www.ford-trucks.com/forums/633697-want-to-lower-egts-2.html on the very thread where they were presented. First CSIPSD posted that I was wrong, then the water injection sponsor weighed into the fray with several posts, and he was supposed to have his technical people check my work and get back, but no one ever posted there again. Well I guess I've already mentioned my heartburn regarding retractions, and I'll just extend that to lack of follow up posts. That's why I always try and follow up when someone posts that I'm wrong, because I think my failure to do so could possibly convey to others that in fact I was wrong, and then they might wind up believing incorrect information due to my lack of response.

Lets talk about "the 6637 is a paper filter" and "Stock trucks come with a paper filter". I'll stipulate those facts as a given, but when it comes to "They have the same filtering characteristics, respond the exact same way to water, dirt, whatever." I disagree on several grounds. The stock filter has a 496 gram dirt capacity. What's the dirt capacity for the 6637, and how quickly does the H20 restriction of the 6637 increase as it accumulates dirt?

I've used both types, and I know for a fact that any under the hood open element filter responds differently to water and dirt compared to one that's in an air box. I'll just quote reasons 3) and 4) from my own thread concerning why I don't use an under the hood open element filter for towing.

3) An open element filter is subjected to all the dirt and dust that gets into the engine compartment. It gets coated with oil fumes, dirt, and grime, just like everything else in a typical engine compartment. A filter in an air box with an inlet leading directly to ambient air, only has to deal with the dust that's in the air actually being used by the engine. I can wipe the top of my air box clean, and after 2 or 3 hours of towing pull into a rest stop, and the air box is dirty again. The way I see it, that's an extra amount of dust that would've wound coating my filter if it hadn't been protected by an air box.

4) Condensation! Yes, I mean inside the engine compartment as well as all over the outside of the truck and RV. It's happened to me many times when camped out near the ocean and gulf. This might not be a big problem for an oiled type element but it's not good for a paper one. Even high humidity has made papers inside my RV so limp that I've had to hold them with both hands to read them.

I quoted SolidGround whose 6637 collapsed and got sucked all the way through his turbo. I also gave a link to Heavy-Duty Diesel Engine Air Filter Collapse that mentions moisture and possible water intrusion from just washing the truck as a possible cause. Everything considered, I don't think your statement "Name one single instance where that has ever happened in real life." was deserved, and it's certainty not accurate.