Modified Air Cleaner Design, Would It Help?

[LastFbody]

So I saw this in a video awhile back, what it looks like is this guy cut the sides of his air cleaner off so the filter is exposed on all sides instead of the normal 3 or 4 inch wide hole, kinda like how air cleaners were on old muscle cars. I'm thinking of copying him, but I've never seen anybody else do this and I've barely seen any conversation about it.

Is there any reason not to do this? It seems to me this would give the motor a little more air, even if its still engine bay air. Also unlike the image I don't have a turbo.

 

[ken]

You can do a test to see if it would make enough difference for you. take the lid off, turn it upside down and tighen it down. You will notice the drone noise will get MUCH louder. I noticed a seat of the pants difference in acceleration. Yes the engines are starving for air. This was done to detune the engine. I am using a civi filter housing from a 93 model with a ram air set up. Much quieter and more seat of the pants power.

 

[LastFbody]

I thought about that, but the factory air cleaner has a 2 or 3 inch step down in the bottom plate, the studs aren't long enough to take up that distance if it were flipped over. I guess I could try putting in longer studs just to test it and see if the noise level is tolerable, rather than buying a 2nd air cleaner to butcher.

I like your newer civi air cleaner, thought of making something custom like that, but I'd have to use a smaller group battery like you have to make it work. I have the original style mega batteries that fill the whole battery tray, no space for a snorkel.

Not necessarily looking for more power, just better thermal efficiency. I've always had somewhat of a black smoke problem and I've turned the fuel down once which helped a bit. I figure it's easier to add air than take away possibly too much fuel, then have to take everything apart again and bug a friend to turn the crank to change fuel delivery again.

More power isn't a bad thing though.

 

[Two Stroke Madness]

The pic in the first post... did anyone else notice the odd turbo setup going on there?

 

[LastFbody]

Yeah it looked pretty wacky to me too. The video its from shows he has his motor tuned pretty badly too, it smokes like a tire fire at almost all rpms higher than idle, and thats when its in park. My truck with its initial dangerously high fuel delivery rate and no turbo would only smoke when it was under load in gear. In park exhaust was invisible at all rpms.

Only possibly worthwhile idea he had is the filter assembly, and even that might just be too darn noisy like ken said.

I'll get some longer studs and test it out this weekend and report back.

 

[1StumpJumper]

The turbo setup is not too odd, it is an ATS.

 

[ken]

I thought about that, but the factory air cleaner has a 2 or 3 inch step down in the bottom plate, the studs aren't long enough to take up that distance if it were flipped over. I guess I could try putting in longer studs just to test it and see if the noise level is tolerable, rather than buying a 2nd air cleaner to butcher.

I like your newer civi air cleaner, thought of making something custom like that, but I'd have to use a smaller group battery like you have to make it work. I have the original style mega batteries that fill the whole battery tray, no space for a snorkel.

Not necessarily looking for more power, just better thermal efficiency. I've always had somewhat of a black smoke problem and I've turned the fuel down once which helped a bit. I figure it's easier to add air than take away possibly too much fuel, then have to take everything apart again and bug a friend to turn the crank to change fuel delivery again.

More power isn't a bad thing though.

You can get some metric all thread from Fastenal and using a hack saw cut the length you need. Or just for a quick test, run it with the filter off just for a short test run. I used the newer housing and the ram air because the drone noise got on my nerves after a few hours . It's is way quieter now. I plumbed it into the knock out opening between the rad and the battery. So fresh air is being rammed up the tube. I seriously dout that it is enough to provide any boost pressure. But I would think it is providing a lot more air than the engine having to draw it in through that small hole.

 

[Russm]

You can do a test to see if it would make enough difference for you. take the lid off, turn it upside down and tighen it down. You will notice the drone noise will get MUCH louder. I noticed a seat of the pants difference in acceleration. Yes the engines are starving for air. This was done to detune the engine. I am using a civi filter housing from a 93 model with a ram air set up. Much quieter and more seat of the pants power. View attachment 745217

Is that one of those rain gutter extenders that you used for the intake tube?

Do you happen to know what model year Chevy stopped doing the round filter housing with your larger opening? 50 mile drive to pick a part I want to be sure they have it.

Sent from my LM-G710 using Tapatalk

 

[Keith_J]

There isn't any measurable restriction through the stock snorkel. At 3600 RPM, the air flow is less than 500 CFM making for a velocity through the snorkel of under 30 MPH. Compressibility isn't a factor at that speed.

Drawing 120°F air from under the hood is more of a performance loss than the restriction. So put a hose from the core support baffle to the stock air cleaner like the non CUCV had and you will be better.

The CUCV was designed to fight in cold climates so this hose was omitted.

 

[ken]

Is that one of those rain gutter extenders that you used for the intake tube?

Do you happen to know what model year Chevy stopped doing the round filter housing with your larger opening? 50 mile drive to pick a part I want to be sure they have it.

Sent from my LM-G710 using Tapatalk

The hose is from LMC truck. It is the same one for a stock CIVI 350 gasser. I used the GM factory plastic connection at the rad core support for it to attach to. I just removed the knock out and instelled it there. I believe GM stopped the 6.2 in 1993. So a stock air cleaner housing from a 88 through 93 should be the same. I also used the single plane intake manifold and passenger side valve cover for the CRD valve. A lot cleaner with less piping.

 

[ken]

There isn't any measurable restriction through the stock snorkel. At 3600 RPM, the air flow is less than 500 CFM making for a velocity through the snorkel of under 30 MPH. Compressibility isn't a factor at that speed.

Drawing 120°F air from under the hood is more of a performance loss than the restriction. So put a hose from the core support baffle to the stock air cleaner like the non CUCV had and you will be better.

The CUCV was designed to fight in cold climates so this hose was omitted.

Agreed. I don't think there is any boost pressure going on here. The opening for the 93 housing is much larger than the CUCV one. The sticker on the housing reads the engine was rated for 175 HP that year. I assume the larger intake hole helps that. So I wonder how much flow is changed if the intake velocity is 30MPH and I am traveling 50MPH? But my main goal was to quiet down the drone of the engine at 50MPH. This helped a lot. Now the loudest thing is the tires. And I can carry on a conversation with the wifey now, much better.

 

[Gunfreak25]

I did the cut up air cleaner mod some years back. Immediently blew my rear main on the way home from the increased air flow ( I suppose an increase in crankcase pressure from better burning ). It did make a seat of the pants difference but the noise was awful.

 

[Keith_J]

60 mph is a static pressure of 1.75 inches water column which is 0.036 PSI. That is about equal to 200 feet above sea level . You get more pressure change from temperature change of 20°. Remember, only two intake valves are open at any given time and this is a low speed engine.

 

[LastFbody]

I tried flipping the bottom plate of the air cleaner, it actually won't sit flush on the air intake that way as it hits accessories around the top of the motor.

Took a closer look at where I could run an intake hose, it looks pretty straightforward actually, even with the huge batteries. That's probably the route I'll go, and probably explains why nobody bothers with the open air filter design.

So an intake hose from a similar year gasser fits up perfectly to the 6.2 air cleaner inlet?

Edit: Should I try and at least track down a factory air inlet (plastic part that goes through the radiator core support for the hose) to deflect rain? Or would covering the end of a hose with screen door material be good enough? I do drive in the rain sometimes.

 

[cruzer747]

I was going to post in my own thread but saw this post was happening so figured I would share a couple of pics of something I found on a civi 6.2 in the junkyard. Looks aftermarket and fairly cheap but it would easily press on to my air cleaner and after reading the thread it looks like it might be worthwhile to clean it up and install it?

 

[Keith_J]

I was going to post in my own thread but saw this post was happening so figured I would share a couple of pics of something I found on a civi 6.2 in the junkyard. Looks aftermarket and fairly cheap but it would easily press on to my air cleaner and after reading the thread it looks like it might be worthwhile to clean it up and install it?

View attachment 745901View attachment 745902View attachment 745903

Nice, cyclonic precleaner. Useful if you travel dusty roads.

 

[LastFbody]

Jury rigged a prototype intake out of hardware store parts, gotta say I'm very satisfied with the results. It takes a lot more pedal before the motor bogs down with too much fuel/not enough air, and throttle response is more crisp. Generally just seems a lot stronger and happier. Noise level is a hair lower than stock, but not much. I suspect I'm still overfueling a bit, but now the motor is getting enough air to make better use of the fuel at least.



Now that I have a good proof of concept I'm gonna bolt the inlet in proper (the green thing in the 2nd image is just the right size and shape to do that) and make a rectangular piece of plastic or metal to jb weld inside the grille in front of the inlet to deflect water like the original correct part. Whatver I use I'll hit with camo black spraypaint so it blends in nice. The rain baffle will probably decrease performance a bit, but I'd rather be safe and less powerful.

 

[LastFbody]

So I made the 2nd version of the intake. This time using rubber plumbing adapters and more hose clamps instead of tape and swearing to hold the rig together. Added plus is that it's a lot easier to take on and off now. Made a rain deflector out of an old battery box I had laying around and JB Weld holding it onto the grille. It's subtle enough where it's hard to spot even if you're looking for it. Green thing on the end of the intake is just sorta sitting there again, it can't be bolted in nice and flush unless I switch to normal width batteries. Since batteries are expensive, I just said "F that, I'll do it next time"


Performance is down a bit from straight up ram air, but it's still a lot happier on the freeway.

3 inch inside diameter drain tile is about the right size. It's a couple millimeters shy of fitting onto the air cleaner nicely though, as I found out after a half hour of swearing at it. 3 inch rubber plumbing adapters can be made to fit reasonably well with hose clamps instead.

 

[Glockfan]

You can do a test to see if it would make enough difference for you. take the lid off, turn it upside down and tighen it down. You will notice the drone noise will get MUCH louder. I noticed a seat of the pants difference in acceleration. Yes the engines are starving for air. This was done to detune the engine. I am using a civi filter housing from a 93 model with a ram air set up. Much quieter and more seat of the pants power. View attachment 745217

I can personally attest to the noise. I modified my housing thinking about maximum air intake and ran it until I got sick of the noise. I now have a factory housing installed again. I will likely try Ken's idea.