I agree..hot air is no good..the cooler the better....the pic below is my AFE..that rubber strip on the top edge seals against the under hood mat and keeps the engine heat out..there is no side against the fender and nothing in the front..all the cold air that can get into that whole front corner under the hood makes it to the filter...I have a very nice whistle..was just a little better when I had the early 99 turbo on there..but its still good..when truck is at idle..that filter sounds like a vacuum cleaner..

 

Well, not trying to be an instigator, but so many folks are running the 6637 that if "hot" air was a problem, we'd know it by now. If you read this thread about under-hood temps, you'll see what I mean. I think it's not as much of a problem as the folks who sell "cold air intakes" indicate. He did the testing with a 6637 installed...

 

Thanx Izzy...I think. Great, so now I gotta change out the filter and explain to my wife why I'm taking pictures of the S&B system to add to my pic's of the TruFlow and K&N filters I'm trying to sell....great.

 

Don't change a thing. Izzy posted a link to an old thread which I've thoroughly refuted in several subsequent threads, but I'm on a plain cell phone connection now and it takes a good 3 min or more to load a page, even without pics and graphics, or I'd go find my threads and post the links here. I'll do just that next week when I get to a WiFi spot. If you want to search for them, look under my user name ernesteugene, and look for cold whether towing report, cold air intake, etc.. to find them.

 

I found the exact titles in my email files, so if you're interested in some of my thoughts, analyses, and experimental measurements on heat, hot air, and PSD efficiency, search for the following titles with my user name, ernesteugene.

Cold air mod for my AIS and estimated HP gain.

Cold Weather Towing Report and HP Analysis!

HP & Torque... the REST of the story!

203* Thermostats, Heat, and PSD Efficiency....The REST of the story!

 

Thanx Ernest. Likewise, I am pulling last year's issue of Diesel Power to re-read the article about how the differing after-market intakes performed.

I'm sure now I will leave the system "closed", but go ahead and add a tube to gain air from my previous zoodad cut.

 

Check my recent temp measurements here in post #5 https://www.ford-trucks.com/forums/641522-alternator-temp.html and the one in post #7! The link that Izzy cited (this is from memory) was a couple of measurements while on a routine half-hour drive, running empty, on a cool afternoon (or evening) with a 60 F ambient air temp, and with a few hard acceleration runs thrown in. Completely different conditions than the ones that I'm talking about.

On the subject of the 6637 filter in general, I think anyone considering switching to one should take the time to read this thread first https://www.ford-trucks.com/forums/636009-kwik-mod-damage-turbo-9.html#post4993642 Below is a quote that I just happen to have in my email archive.

The following is some data on air filters. I think the 6637 is the Baldwin filter in this report, and at 16 inches of H2O, the 7.3L AIS flows an additional 200 CFM. I don't think anyone can go wrong with the AIS because it gives the best combined performance when both "dirt holding" and "restriction" are considered.

Flow Restriction: This report presents flow restriction of a clean filter resulting from an increasing airflow. The differential pressure restriction across the filter is reported in inches of water (IN H2O) versus Air Flow in cubic feet per minute CFM.

The Donaldson filter (6.0L OEM) at 775 CFM gives 4.9 inches of H2O
The Donaldson filter (7.3L AIS) at 700 CFM gives16 inches of H2O
The AC Delco filter at 350 CFM gives 6.25 inches of H2O
The AMSOIL filter at 350 CFM gives 6.0 inches of H2O
The Baldwin filter at 350 CFM gives 5.75 inches of H2O
The Baldwin filter at 500 CFM gives 16 inches of H2O
The K&N filter at 350 CFM gives 4.6 inches of H2O

 

I am planning on doing the ZOODAD mod on my stock 2000 7.3 psd. Of all the pictures I have seen on FTE I don't recall seeing one that had the space between the cutout and the intake tube sealed up (approx. 1' to 1 1/2". This, to me, would give a smoother air flow and wouldn't allow any under the hood air to be sucked in. But I have to wonder, since everyone reports no water getting into the filter element with this mod, does that unsealed space give the rain water, etc. a point where in can leak out before going into the tube. What do you guys think? The seal could be easily done. Please give me some feedback before I do the mod. Any and all suggestions &/or opinions will be greatly appreciated !!

 

Oh for gosh sakes.... The 6637 is a fine filter. Nobody has had problems with it (except for maybe that one person that apparently got a bad one and it came apart).

I think Gene has a serious bias against the 6637, but I don't know why. It works very well, and the intake temps after the intercooler are very telling. Another person took a look at the under-hood temps by placing two digital thermometers in the cab with the sensor of one under the hood and the other outside. Can't find that thread right now. While under way, the under hood temps dropped to within a few degrees of ambient. When stopped, they rose, naturally.

I know there are a lot of folks that run the 6637, and perform equally with folks that run the so-called "cold air intakes". It's your call in the end. Look at some of the other dyno numbers. I'd like to hear more about the thing quoted by Tenn, though. Something's not right. Don't forget that running on a dyno, the truck is sitting still. Not a real "apples to apples" comparison. You can run your own comparison -- make a run with your stock filter, then install the 6637 and see if you can tell a difference. I'm pretty sure I could, but it's been a while since I've done the swap. I'm a bit skeptical that an air filter (a clean one) can make a 25HP difference. Sounds like K&N marketing numbers, honestly.

People can get their hackles up over air filters, apparently as much as oil choices, so I'll leave it there. I'll let the raw numbers of folks running these speak for themselves.

 

Like you Jim, I was concerned with the space between the cut-out and the intake tube. Thus, I paid a visit to Home Depot and found a rubber sleave to fit over the end of the tube and fit tightly up against the cut-out.

As for the cut-out and the large bug collection I was building, I decided to take some 1/4" wire mesh to cover the hole. It worked pretty well. I also painted it flat black to blend in with the surroundings.


It is this same cut-out that I am now going to plumb to my exiting S&B filter box. I think this should do very well in allowing the intake to draw air in thru the grill...as well as gain a little bit of "ram air" affect when at speed...and perhaps some increased intake whistle???

 

Thanks crosbo! What was that rubber sleeve originally designed for, so I will know what to look for at Home Depot? Sounds like a good idea! Did it seal it off real good? Thanks again for the tip!

 

You know Jim, I don't recall. I think I found it around the toilet section. It is a ribbed rubber seal that is about 4-6" long. I had to heat it up to be able to stretch it over the rectangular air intake tube, but it did seal well. I could really tell the air being pulled thru opening.

 

If you want to do alittle more research on crosses, look up satch's thread 6637 cross reference. I found mine for 40.00 at car quest , part number 88637. No one is going to make me change my Sig are they?

 

I'm pretty sure that you've read some or all of the threads that I gave the titles of in my post #20 above, so you should know that my bias is not against the 6637 as you claim, but rather it's against ALL OPEN filters that pull hot under the hood air into the turbo, but since you claim you don't know why I'm against these types of filters, I'll briefly summarize my reasons. First, you should read the recent temp measurements reported here https://www.ford-trucks.com/forums/641522-alternator-temp.html , I reported under the hood temps of 200 F in post #5, and the guy in post #7 reported 300 F! When you tow a grade ANY OPEN under the hood filter will pull that hot air directly into the turbo at the rate of about 400 CFM! I won't repeat here all of my previously referenced analysis of how this hot air reduces HP by at least 7% or more, but I will give yet another reason why this hot air is detrimental. It increases the turbo operating temperature, which in turn increases its rate of wear, but my "wear out model" for the turbo, piston rings, etc... is still a work in progress, and not yet ready to be posted.

The quote from Tenn about the 25 HP increase on the dyno when the 6637 was removed, was from this thread https://www.ford-trucks.com/forums/636009-kwik-mod-damage-turbo-9.html#post4993642 which as you know, discussed possible differences in air flow characteristics for ANY OPEN filter (including the 6637) versus any filter with a conventional air box. Tenn's quote was referring to this discussion, and I don't believe he intended anything negative against the 6637 in particular?

Do you (or anyone else) know if the restriction vs CFM data I cited for the Baldwin filter is the same as for a 6637? If not, does anyone know what the correct data is?

 

Real quick Gene, quick summary, you are against the open filters 1- vortex created ( theroy ) causing Turbo's to blow
2- hot air intake

Are the cone filters better then the stock box's with an aftermarket filter. OR do you leave the stock filter in, unitl you do the 250.00 AFE intake system? I ask, because I bought the 6637 for better filtration, based on everything here about leaky stock boxes, I dropped my K&N only because it was in the stock box. But I believe they are fine if you maintain them.