I just finished making my own aircleaner.:cool: I wanted to let the engine breathe easier, with unrestricted, cooler outside air, so I wanted to increase my inlet size. The intake muffler was off already, but even like that it was 4" dia at the radiator support, going to a 2" dia to fit the 2"x4" oval in the factory aircleaner.

Since the 2"x4" oval aircleaner inlet was maxed out with the factory setup, I had to go bigger. Was decided that I could stack (2) 3" filters, with the orginal size diameter of the orginal 4". So with 6" filtration, I could increase my inlet from 2" height to a full 4" diameter opening.

I didnt want to cut up my old base, and I had free sheetmetal to use. I used the old base as a model and just increased the height of the sides really. using the base as a model was key, since its designed to fit over the 2 cdr tubes that go to the intake. Also, I was able to use the original cover, and i painted it all glossy black.

So while making it, I remembered that there was a second air intake opening on the radiator support, located on the drivers side. Because of the longer HD radiator, it is partially blocked by it, as well as the aux battery. But I thought I could still get to it, and besides it cant be any worse then the orginal factory air intake. So instead of cutting 1 4" circle in my new air cleaner, I cut 2 for a dual inlet setup.

the truck orginally had the inlet box which seperated air and water. It looked pretty restricting, so i went to the junkyard and bought 2 of the standard straight through design inlet connectors, the kind that roatates in. they are a tad larger then 4" diameter, so that worked out as well.

I had to make 2 new cover bolts, since with the increase of height they became shorter. I just cut a 6" piece or rod, threaded the one end for the orginal wingnuts and wielded a bolt to the other end. worked like a charm.

for new intake hose i used 4" aluminized clothes dryer duct. unrestricted, flexable and its fire resistant it worked great. hose clamps on both ends.

like imagined, the second intake was a real pain to install. I couldnt get the hose on with the radiator in the way, so its partially past the support but its still in there tight. Plus with alot of bends... going down and around the battery tray, then back up and over the ac compressor. One of the bends is pretty tight. but from what i can see its still holding a 2"-3" diameter. the dryer duct helps hold that shape, and its stronger then imagined, on more the one occasion I thought it would get cut.

So even though the secondary is not true 4" and its got a few bends, it has to be equal to the factory setup, and even if it helps breathe alittle, then its worth it in my opinion.

let alone, it looks really cool to see dual inlets go into that aircleaner!

One problem I imagined would happen, but didnt. the orginal aircleaner has a detent in the front to clear the fuel return line on the IP. I didnt add on to my design, and it just clears it. Possibly the new cleaner sits a tad taller of the intake manifold. Just to be sure, I added a piece of hose there to protect it.

one small problem was that i was a bit off on my new height for the sides, the filters didnt stay in place. a solid clean piece of cardboard fixed that problem.

being recently finished I havent driven it around much yet, but on my one drive it seems the speedometer likes to move up faster then it used to, especially in the higher range. there also seems to be a difference from standstill takeoff. I will update on differences when they come, plus I might have to tow a boat soon so that will be interesting to see if any improvments.

most people I asked about stacking airfilters, was that it was pretty noisy. I have not experienced any of that yet and I doubt I will. besides, if it does happen....the louder the better! :ro)

the cost was barely any. sheetmetal, the rod(for the bolts) and the means to weld it was free. dryer duct was around $11, and it came in 8' lengths, which was enough for both inlets, but not by much. 4 hose clamps, about $1.25 each. and the paint. the 3" filters are about $5.25 each.

What does everyone think? Any questions, ask and I will get back to you.

Got Pics??

Yes, I forgot to mention that. I will have pictures when it stops raining.

Rain? Sure would like some of that!!! Damn its hot.

picture number 5 is the one showing how tight the secondary inlet is, with the battery holder and the radiator in the way.

Looks GREAT!!! :ro) :ro) :cool2:

You did a great job!!!! I would suggest that you replace the cardboard spacer with a solid rubber spacer. The cardboard will eventually collapse enough to leak air. The air filters come with a rubber mounting so one or two glued together if necessary might work.

Thanks guys!
I was trying to figure out a easy way to do better then the cardboard. A guess would be that im only off 1/8". I tried to get it so with the lid pushing everything down, it would smash the cardboard solid and make a firm seal.

What are these rubber mountings that come with the filters?

I believe my measurement is off due to making the lip for the cover. i took in account for it, but being first time metalworking, some of the finished product isnt really 100% accurate.

I think I still have a drawing and measurements for anyone who is interested.

Sure am!!

Mike, cool. I will find it and post it soon as I can.

I drove her today. To me, there is a difference. unlike what i heard and thought would happen, driving around 50-55mph its quieter then it used to be. like its not struggling for air anymore. also easier to mantain speed as well just cruising is smoother.

also seems to be a difference on quicker response with higher throttle. i expected that as well.

i know its not a dyno but I tried to keep my old driving habits to have a base to compare to.

going to look into turing my fuel up, if its not already..to get maxium benefit.

will be towing the above mentioned boat thursday. will update again then.

I towed the boat and there was a difference. it just ran better. but, while trying to get going on a major road she had no power in lower rpms at high throttle, like when it shifted. yuck. halfway in the gear she caught and had power again..then shifted and it was gone again. and im not talking about overdrive.

thats never happened before.

turned up the fuel today, 1/6th increase:cool: . was a pain but worth it. and I bet it fixes the above problem...seems to me just not enough fuel at wot with a load on it. coming back home empty there was no problems again. another tow will sort things out.

I really like your setup on the tubes! I have often wanted to do something like this with a K&N or like type filter and run a tube to there filter housing mounted in the engine bay.

My air filters have a rubber base on the top and bottom of the air filter to seal the filter to the air cleaner. I suspect that each one is about 1/8th in. thick. I thought it might be about the same thickness as your cardboard and it would not disintegrate with moisture and vibration.

@TFLundyB275
looks great what you did. i am working on a similar thing.

i am living in a rainy area so an important thing for me is how did you prevent the rain coming into the air cleaner while letting the air in ? yes, you described it but did not really figure that out.
do you have a pic ?

Thanks for the compliments everyone. Im still looking for that piece of paper I had the measurements on, for mangus and anyone else whos interested.

Laster, im not sure why some trucks have them, and some dont. maybe it changed after a certain year for the 6.2L.
orginally I had a factory water/air seperator box attached to the rad. support. looks rectangular, with 3 openings, 2 air at top, 1 water at bottom. the air has to go down, then back up to get to the engine. the water will go down, and come out the hole at the bottom. seemed air restrictive to me.
other trucks have a simple circle type plastic thingy that you just insert, and turn into the rad support. the front is solid so water is blocked. behind it is 4 openings on the side for airflow. hard to explain, i will get pictures of both types for you.
I went to the junkyard and grabbed 2 of them, one for each side. they were a plenty.
how is the system on a military 6.2L truck? never seen it.
hope this helps. feel free to ask for further explanation.

I have often wanted to do something like this with a K&N or like type filter

I would guess that a K&N or other type of free flowing filter would be even less restrictive in this case. but now Id have to by two of them. I looked into it pre production, but they didnt make a filter the stacked dimensions. 6"x 11"R i think.

no hard facts of course, but I wouldnt be surprised if my stacked filters are the same airflow to a single free flowing filter, not including the second inlet.

sorry the one set is dark. I hope this clears things up.
what do you guys think about the new and old style, about restriction?

ok now it's clear to me.
i've never seen something like that, the military truck has just the air cleaner case with the eliptical air intake, getting hot air from the engine compartment.
for the old separator i am wondering why the air that is pressed by the speed of the car should not go the easier way to leave the system at the water outlet. ok the engine draws it in but maye a part of the aif low might be lost.

the newer one does not give the air the choice. however it looks to me that it puts a higher resistence into the air stream.

well water separation will probably always be a tradeoff.

i have an alternative in my mind with the cover of a ventilation intake.
over the weekend i will do some measurements and post it.

for the old separator i am wondering why the air that is pressed by the speed of the car should not go the easier way to leave the system at the water outlet. ok the engine draws it in but maye a part of the aif low might be lost.

the newer one does not give the air the choice. however it looks to me that it puts a higher resistence into the air stream.

I had the same thought, that some outside air will just flow out the water outlet. at the same time, the thought of hot engine compartment air could be going in. neither is good.

I picked the "new"type because of simple install, plus had the 4" diameter needed. if your support has the cutouts, it would be simple to go to that. Im not exactly sure how that military setup is, but sounds not so efficent. please keep me posted about your alternate way, im interested and open to see what you got in mind.

as far as the "new" one, I dont see how its higher resistance. the old one has a maze to travel. on vehicle movement Im thinking there is plenty of forced air against the radiator support section, where the 4 openings on the "new" type would breathe it in. from there on in, its a straight run.

what do you think?

by the way, I was in washington state for a good while with this same truck, but before this modifcation. I would not hesitate using this system there during the rainy season at all.
plus I have found the new kind of inlets on diesel and gasoline trucks from 1983 up to 1988 until the style change. if it had a big water problem, I would think gm would get rid of them.

ok, i think i've got the point now. the round plate and the four openings are outside and just the short tube is inside the engine compartment and there you can attach the hose.
in that case i agree, the air pressure around it should be sufficient.

i will build such a part out of a waste pipe and compare that, too.

the round plate and the four openings are outside and just the short tube is inside the engine compartment and there you can attach the hose.


thats it exactly. and I believe the plate would stop most if not all incoming water. let me know how it goes, and pictures if you can. good luck.

Still working on drawing the plans up. Sorry taking so long.

ok, it took a while for me to take the pics.

the way i tested the air stream and the water blocking:
i made a big panel with a round hole with 4 inch diameter.
i put a huge fan in front of it and measured the air velocity behind the hole.
then i took a hosepipe and splashed water onto the panel.

i did the same with an assembly similar to what you got from the junkyard. i made it out of waste tubes. (see pic of the front grille)

then i took a cover from ventilation tubes and tested it also. (two pics with part on cardboard)

the result:
no cover: air stream 20 m/s (meter/second), water: really wet
waste tube: air stream 18 m/s, water: just a litte hazy
ventilation cover: air stream 17 m/s, water: really wet !

bottomline: as you said, GMC decided for good reasons to keep that design.
so i followed the advice.

now i can continue to build the second tube to the air filter.

TFLundyB275, would it be possible take grab two of the new separators next time that you go the the yankyard and send them to me.
on the yankyards here there are no pickup trucks.
i pay for the shipping, of course.

Sounds good. interesting test. i was able to go today and get you a pair. woudl like to see the results of your mod and compaire to mine to see just what kind of differnce is made.

from your picture, looks like you will have to move the drivers side horn over to make room.

you have a private message inbound.

Laster, your air intake set-up looks almost identical to the Banks 6.2 Ram Air Intake system that I have installed in my '86 K10 Regular Cab Long Box. It's the same cold air intake set-up that they sell with their Side Winder Turbo system. Here is a link for it here:

http://bankspower.com/System.cfm?appid=AC02&sysid=SC02# (http://bankspower.com/System.cfm?appid=AC02&sysid=SC02)#

This plus a decent free flow exhaust really makes a noticable difference in the old 6.2's, giving you better performance and increased gas mileage.

There are two different part #'s for this air intake. 49019 is for 82-85 model years, and 49017 is for 86-89.

:grd:

heres the measurements. i hope they are close to correct. I cut everything slightly bigger just to make sure. the actual base on mine is a tad to big..I had to put a spacer inbetween it and the return line on the IP. any questions ask, comments please post.:cool:

sorry about the drawings, the forum wont let me post them any bigger...these drawings are available for use by any and all diesel place members.:ro) pm me and i will try to send full size to whoever really wants them.

Hi TFLundyB275, finaly i can send you the pictur of the setup i come with ,each side are oversize to 2 1/4"I.D.to match the exaust manifold diam ,same volume capacity in/out.

Hi TFLundyB275 ,as you ask i joint some picture of my setup on the driver side just need a air/water separator , very rare nearby i tink make two from aluminium sheetmetal if cannot find shortly . I move my horn on driver side to a lower location :bumper level.

As you see on the pictures the radiator is HD 4W from 86 ChevyVan 2500 , minus 2 inch wider, so i clear the factory air inlet,

Yes very good, thank you. that explains how you made that happen. the stock 6.2 radiator blocks the second passage..but your radiator clears it, nice. thanks for the pictures and the engine looks pretty good all painted up!

tigman ... very sharp looking

how many turns did you (anyone who has turned up their pump) turn up thiere pump after modifying thier air intake set-up??

I hear most should only go about 1/8, anything more is a waste of fuel. but those are for guys that only really just take the air intake muffler off or something.

I turned it up 1/6th of a turn. but I did a radical modfication. i actually couldve done a little more. I know D. Cam has ran some fully turned up with no problems(I dont remember any problems..)

best way to tell is to have a hint of smoke at wide open throttle.

and having a opened up air system is only good if you have a good open exhaust. more air in means more exhuast out. as a rule at least dual 2.5" exhaust.

i also change my aircleaner, but i modify the baseplate of the original aircleaner, i use the toyota land cruiser 4.5 air cleaner. it is about 20cm high and 35cm in diametre. the engine goes very well now it dont smoke black any more under load, and it goes. between robots in town the 6.2 out perform a ford ranger 4000i v6

between robots in town the 6.2 out perform a ford ranger 4000i v6

Robots? :confused: :D

ok,
between stop streets about 300 meters inbetween

Was thinking of doing something like this by just taking a pair of air cleaner housings and stacking them up. Did all the 6.2L engines have the same air cleaner housing, or do I need to search the salvage yards for a specific year range?

I cant speak past 1988 or so year trucks, but at least 1982-1988 has the same air cleaner assembly. you can find them kinda cheep on ebay once in a while if you have a hard time finding them.

when I started looking into doing an aircleaner mod, it was mentioned to me to stack 2 aircleaners. i considered it, but eventually did custom.

it would help alot if you could do it, a pain for the full custom was designing/building the bottom to match the curves for the intake and CDR hoses.

besides not having any junkyards with 6.2's around to grab 2 aircleaners, since I didnt want to cut mine up....if you stack 2 orginal air filters, the hood wont close..or if you get it closed it will bulge. original filters are 4" each. so if you stack 2 aircleaners make sure the sucker fits..you may be forced to use 2x 3" filters like I did...then make sure the sides are the correct height so there is a good seal between the top lid and the filter.

mine was a bit off and I have to really put the lid on tight to have a good seal. Ive also had to add a spacer under the filter to build it up slightly. i still hope its tight enough :rolleyes:

I like it... looks mean ;-)

Cool mod 2 air inlet thanks for the idee i have my own idee use my stock air bold and cut the second one from a other one and weld it together and cut a matching hole same size as a stock one and make a safari Snorkel

Hey Guys,

I have been reading along throghout this entire thread and would just like to say that it has been extremely interesting and helpful. I am building a dual intake system with Tigman's help and together throuhg him and this thread, i am 100% more educated.

Thanks for your ambitious minds,

Grizzly

FYI, as an alternative to total fabrication -

When I was discussing this concept with TF, I suggested that he locate a pair of Olds or Buick or Pontiac 455 air cleaners for the modification, as they use the similar diameter air filter element, but taller, and usually have dual intake ducts.

Easy to section and pop-rivet two together, using RTV as sealant, and much more workable for those with little access to sheetmetal tools.