Air Cleaner Advice

[ClydesdaleKevin]

Just put in the new Edelbrock 1411 carburetor, and while I now have all my hill climbing power back, I'm still getting the same lousy 6mpg the malfunctioning Rochester Quadrajet got.  The RQJ when it was running correctly was giving us over 8mpg on average, then when it malfunctioned went down to 6.

To eliminate it from the equation, I'm putting in a new EGR valve this week.  I'm also going to simplify the vacuum line routing and reroute and eliminate a lot of them.

My question is about the air cleaner housing. 

We are very rarely in super cold driving conditions.  Usually we are driving in moderate temperatures, and sometimes in very hot, but with all the cooling system mods I added to the rig, the transmission temp never gets over 150-200 anymore, and the engine stays a constant 185 for the most part, and never gets over 220.

Our RV is a basement storage model, which means the engine isn't as boxed in as a lower height model where your doghouse encloses the whole top of the engine.  There is much room around the top of our engine, and as much airflow around it, as any early model muscle car.

So my question is this...would it be a bad idea to replace the stock air cleaner housing with a non snorkel type open element air cleaner, like an Edelbrock?

From everything I've read, Edelbrocks get the best mileage and performance from full air flow.

Our 89 has a snorkeled air cleaner housing, and then has a carbon filter, very clogged, permanently installed in the air cleaner housing.  I'm thinking an Edelbrock open filter will get better airflow, and ergo better gas mileage and power.

I would have to cap off a few lines and add an breather to the valve cover, but that's no big deal.

Also, with an Edelbrock filter housing I wouldn't have to use the crappy plastic spacer that doesn't make a good seal with my new carburetor.

Do any of you foresee a problem with this plan?  I'm thinking that because my engine sits so low in our chassis and has full air flow all the way around it...only the high profile air cleaner sits inside the doghouse cover...that a full flow filter housing would be the best bet in ensuring maximum airflow to the carburetor.

Yeah, it wouldn't be cold air intake from a snorkel, but there is a LOT of room around the engine...its not like an old Dodge motorhome.

Gonna tackle this project on Monday, so any input before then will be greatly appreciated!

Kev

[ClydesdaleKevin]

I'm going to tackle this project on Monday and Tuesday, so if anyone else has any advice on my air cleaner options, I would be much obliged.

So far I have a few choices. 

One option is to remove the stock air cleaner and replace it with a 14" open element Edelbrock air cleaner.  Since my coach has basement storage, the engine rides lower in the chassis relative to the coach above it than a non basement model.  In other words, its open to the air on both sides and isn't nearly as enclosed as a coach built lower to the ground.  The entire engine lives below the coach floor level, and the only part of the motor that sticks up in the doghouse is the air cleaner...and with the stock air cleaner, there is plenty of clearance above it.  What this means is that the engine heat isn't trapped in the doghouse and around the carb as much as in an older lower motorhome.  I would imagine the heat around the carb is comparable to the heat any muscle car would trap under the hood, and a snorkeled system isn't necessarily needed.

The above option would require a valve cover breather, which is just as well, since the breather hose going into the stock air cleaner gets oil all over the paper filter, even though its got a filter. 

I would also have to remove several other lines and cap some of them, and cap some vacuum lines and reroute some, but now that I understand the vacuum system on this engine, I'm not hesitant to do it...and because I'm not worried about emission (both legally and ethically...a more efficiently running engine is going to put out lower emissions), it seems like a viable option.  The AIR hoses would have to be removed from the equation, at least the ones that go to the air cleaner,  but that's easy enough to do.  Just pull the hoses at the pumps and let them blow air into the engine compartment.  It won't hurt anything, and eventually I could even remove the air pumps, cap off the metal lines going to the exhaust manifold, and get shorter belts.  I could leave them in place for now though and just let them blow air into the exhaust manifolds...and if I understand the vacuum line going to the AIR valves correctly, if I disco the fulltime vacuum lines going to them, the valve will close and they will only blow air into the manifold.

What the above would mean is WAY better air flow to the carburetor, and very few vacuum lines.  The distributor would be the only thing attached to the ported vacuum, and just the EGR valve, the PCV valve, the transmission control, and an accessory line would be attached to fulltime vacuum (and of course eventually a vacuum gauge on the dash!).

Option 2:

A heavy modification of the stock air filter housing.

This would involve removing the charcoal filter from the stock air cleaner housing.  Not sure how to get it out, but I have a hammer and a grinder with a new cutting wheel, and I'm not afraid to use them!  My charcoal filter is getting pretty clogged, and according to everything I've read, they are only designed to last about 100K miles, and then the whole filter housing is supposed to be replace...and its NOT a part you can get anymore!

Because of the fitment of the stock housing on an Edelbrock, in order to clear the fuel line (tried the Edelbrock banjo fitting and still had clearance issues), I have to use a 1/2 inch air cleaner spacer.  The only one I could find in a hurry was from Mr. Gasket or Specter.  I went with the Specter because it was slightly thicker plastic than the cheap Mr. Gasket, but I still don't trust it.  Even the Edelbrock brand was cheap thin plastic.  I did find aluminum thicker versions at Summit Racing, but don't have time to order them.

So what that means is that if I use the stock air cleaner, I'll have to get a high heat epoxy, and epoxy the spacer to the bottom of the stock air cleaner, since it makes a lousy seal, even with a spare air cleaner gasket being used.  Doable, but another step.

Next I'll have to put caps on all the lines that come into the stock air cleaner that I won't be using.  Including the breather intake.  I would still go with an Edelbrock crankcase breather.  If I keep the stock air cleaner on the Edelbrock, then I would just leave the AIR hoses attached to the air cleaner, but eliminate the other lines that come into it, like the preheater (already eliminated anyways), and the other hoses that aren't AIR related...otherwise the vacuum routing would still be simplified as if using an aftermarket air cleaner.

Its actually way more complicated to keep the stock air cleaner.  The only advantage I can see to use the stock air cleaner is to keep the snorkeled air intake, but after a lot of reading on 454s, they don't seem to mind warm or hot air...its the cold they don't like.  Fortunately, we don't usually travel is cold weather...usually mild weather and occasionally hot weather.

This second option would also involve a K&N air filter in the stock air cleaner housing, to compensate for the reduced airflow of the snorkel system.

Expense wise, I think it would be as or even more expensive to keep and modify the stock system as getting an aftermarket open element filter system, and it would be way more involved time wise.  K&N filter, oil for the filter, caps for the unused lines, high temp epoxy, breather (same for either option)...and then all the additional time involved to knock out the carbon filter neatly, clean the stock air cleaner housing around the base thoroughly, epoxy on the spacer and let the spacer epoxy cure completely, cap off the lines not being used, etc.

The third option is to leave it alone and drive.

This isn't an option, since I am SO not satisfied with 6mpg!

What do you guys think?  I'm thinking option one would be my best bet.  Pretty chrome too...lol!

Option one would also be a not very expensive experiment.  If it failed and I had problems with it, I could always go back to the stock air cleaner!  I'd keep it around a while, stowed in the Jeep, until we got to Arizona.  See how everything was running with an open element air filter.

Another thing I was thinking of doing was either replacing the EGR valve and making sure it was clear of carbon build up, or else capping it off completely with one of those aftermarket EGR eliminators.  That would get another vacuum line out of the equation and get a possible current or future vacuum leak out of the equation for good.  Eliminators are cheaper than new valves, so I'd probably swing that way, IF I can get the part in time.  Otherwise I'll leave the EGR valve alone until San Antonio and only replace it if I'm still not seeing a significant improvement in gas mileage.

The last thing I'll do, which will be done no matter which option I choose, is to loosen up the electric choke a bit on the Edelbrock.  Factory set a little to rich in my opinion.  It takes a LONG time to open all the way.  There is a lot of spring tension on it when its cold.  I don't think it has to be as tight.  And while I'm at it, I want to lean out the idle mixture, not too much, but just set it according to the way they do in the video provided with the new carburetor.  Its easy on an Edelbrock. 

I'm thinking either option will improve my fuel economy and power, but option 1 seems to be the easiest and at least AS affordable option as option 2.

What do you guys think?

Kev

[bluebird]

Cold air kits maybe the way to go on carburated engines, but on a fuel injected  engine will cause a decrease in fuel economy. I lost 1.5 mpg on my corvette when I installed a cold air kit on it last winter, but it sure does run better. I would NOT use an open air cleaner on the coach. 1 you will have a LOT more intake noise, 2 you will be using the HOT air instead of the cooler air it now uses. You want to pull the air from in front of the radiator not behind it. You will be hard pressed to find a carb to deliver the fuel economy the a properly tuned quadrajet can deliver. Although it's very hard to find a GOOD quadrajet  guy anymore, but they're still around, you just have to find one. Make sure the distributor is right, plugs, and wires. I could never get over 8 mpg on my old Itasca, usually 6 or a shade over no mater what I did. When I was pulling my race car with it and over 55 it'd be a little over 5 mpg. That's why I traded up to a coach with injection and overdrive. It made a huge difference. I can pull 9 to 12 depending on wind and speed I drive.

[HandyDan]

   
This is the way my HR came from the factory.  It had the propane, gasoline option and the propane was fed through the air cleaner.  As you can see, it isn't too much different from the Edelbrock.  I removed all the propane systems and replaced this air cleaner with an Edelbrock.  It seems to run just fine but there is a lot of intake noise that I doubt you would have with a snorkel cleaner.  Not sure if this helps any, but I don't think you would have any problems with option one.  Even with the Edelbrock there is a large hose on the bottom that goes to the PCV valve in the rocker valve cover.  You have to position the air cleaner just right for that hose to clear all the spaghetti under the air cleaner. 

[ClydesdaleKevin]

Thanks for the advice so far...still not sure which way I'll go with it, so I added a poll to the mix...lol!  Let the voting commence!

Kev

[ClydesdaleKevin]

Keep the polls rolling in!  Even though I found a cheap deal in an open element Edelbrock housing and filter and matching breather, none of us know how it will turn out in the end, so I can still modify the stock air cleaner if needed as we progress on our journey.

I could even go with one of the modern cold air intakes, since they make adapters for carburetors.

Keep 'em comin' folks, and I'll let you know how my experimental mods work out on the road out West!

Kev

[tiinytina]

When we put the Edelbrock on we put on a KN open filter system.  and yes in cold weather we got 3.2mpg... on flat 95S.... our mileage dropped to 6 hauling empty over all... so.. that came off, the old snorkel went on and we put a KN filter into the old snorkel.  Our original snorkel fit right around the Edelbrock  no mods that I know of.   

From Ace mechanic the 454 LOVES hot air intake,  Even when just warming up.  (The banks system has the intake for the snorkel on passenger side. We have a RAM intake in front passenger side top left of the radiator.  The snorkel hose is kind of pinched stuffed in between engine and doghouse but seems to get enough air head on into the wind.   

From another forum (P30 Yahoogroups) also got advice to make sure that there was a cowling in the wheelwell (ours is missing) It should hang/attached between wheelwell and engine... so you can't see the engine through around the tire. Since the engine tends to run on the warm side...  this cowling directs more air over/around the engine vs this being open... though the logic is somewhat confusing

Tina

[ClydesdaleKevin]

Thanks Tina!  Our coach is kind of a weird mutt though.  Since we have basement storage, the coach itself sits way higher over the engine than most vintage rigs on P30 chassis. 

From either wheel well, I can see the entire side of the engine, and it has lots of air flow.  Lots above it too...

I'm thinking I should try the full flow system first and see how it goes without modifying the stock intake, in case I want to use it later if it doesn't work out.

Another option that I haven't priced out yet...and since its involved I don't have time for NOW but might implement later on...is the cold air intake systems available out there with conical filters.  They make them for carbureted engines, so you can get adapters and whatnot to do pretty much anything you want.  But with the 454 they sort of LIKE warm air, so I'm not sure.

I'm going to go with this experiment first and see how it pans out.  Worst case scenario I could always sell the parts on eBay and not be out too much money.

Kev

[ClydesdaleKevin]

Getting excited!  Parts should be here early on Tuesday!

EGR will be blocked off, there will be VERY few vacuum lines, and the Edelbrock will have full air flow.  And the idle mixture screws will be set on lean, the choke will be set a bit leaner to open earlier, and the distributor will be directly fed by a ported vacuum, and be the only thing on the ported vacuum tube on the carburetor.

I might even advance the timing, just a little by ear.

If this all works out, then say goodbye to the AIR system as well in the future!  Shorter belts, no pumps, and blocked off fittings at the manifold.  We'll see how it goes.

Kev

[ClydesdaleKevin]

Got all the parts today, and after finishing the headlight project, started and finished this project, start to finish.

The first thing to do was get rid of unnecessary vacuum lines.  Turns out all the lines to the main huge port on the back of the carb had to do with cruise control.  Removed and the hole on the back the carb plugged.  Glad I saved the plug from the carb install kit!

EVERY other fulltime vacuum line that was plugged into the fulltime vacuum port on the carb went to emissions stuff and valves and whatnot, nothing to do with running the engine.  Most of the vacuum lines going to the transmission were ported into the manifold directly.  There was ONE line coming out that was full time, leading to a steel line routed along the left valve cover that disappears under the rig, that I was uncertain of, and it might have to do with the transmission, so that is the only line I left attached to the fulltime vacuum port on the Edelbrock.  The only vacuum line left on the ported vacuum is a new direct line to the distributor advance.

Patti's eyebrows sure kept climbing higher and higher as I kept increasing to the pile of unneeded vacuum lines and emission parts and valves and plugs and housings and whatnot! 

So now I only have 3 vacuum lines going to the carburetor...the mystery fulltime lead that might lead to the transmission, the ported lead that goes to the distributor, and the fulltime big lead to the PCV valve.  There is another vacuum line, and pair of lines actually, that lead directly from the manifold and down in the direction of the transmission and thing below, so I left those alone.

Most of the AIR hoses were removed as well.  I still ran a direct hose from each pump to the AIR valve housing on each side to keep the air flow going.  The housings suck air, and the hoses blow air, but without the hoses, there is too much noise and exhaust smell coming from the valve housings.  A simple hose rerouting solved that problem before it even began.  Eventually I want to remove the pumps completely, install shorter belts, and block off the ports to the exhaust manifold.  A future project!

Next was the removal of the EGR valve, the cleaning of the gasket surface, and and the install of the block off plate.  I put a very thin coat of RTV red gasket sealant on both sides of the gasket.  There sure was a lot of carbon deposits on both ports!

The next step was to replace the breather o-ring where the breather hose used to be, and push in the Edelbrock breather.

Next, I checked the fit of the new Edelbrock aircleaner, and while it would have fit tightly over the stock arrangement with the fuel line coming straight out, it was a hard fit requiring a tight wingnut setting to get the aircleaner to seal completely.  Since I already had it, I installed the banjo fuel fitting, and the air cleaner fit like a glove!

Started the engine and it started right up.

Let it warm up completely.

Kicked it down and the idle was way higher than before!

1000 rmp!

I adjusted it down to 700.

Then I decided to adjust the idle mixture screws on the side of lean.

On the Edelbrock, very easy to do.  Warm it up and start turning one screw inward until the idle drops, then back it off 1/2 turn.  Do the same for the other screw.  DONE!

Even the screw heads ended up in the same position...gotta love Edelbrock!

Gonna leave the choke adjustment alone for now, and see how it goes...gonna be cold in the mornings on our trip out west!

Let the engine run for a while, reving it now and then.  This is the first time since I've owned this couch that it dropped immediately to idle with no fluctuation!

And a perfect 700 RPM.

Long story shore, eliminating as many vacuum leaks as possible, including the EGR, and then setting the idle mixture has seemed to make this engine run better than it ever has since we owned it.

I'll let you all know how the next road test to San Antonio goes!

Kev

[tiinytina]

Next time through MD I may have you stop and do all the above to Gone! LOL....  I ended up giving the $125 KN assembly to a buddy of mine for his work box truck... works fine for the engine in that thing....

I'll have to pull the dog house and see what vacuum lines we still have now that the AIR system is gone. Know the EGR is bad already. We replaced all the vacuum lines though.... and those to the AIR system were plugged.

The 454 do like warm air, known fact... so hope all your mods and the filter work out for you but I was glad I kept all the old snorkel parts etc... because I painted them up and popped them back on after that 3.2MPg drive from MD to NC and back in cold weather... she was drinking through the McD's milkshake straw on that run....

tina

[ClydesdaleKevin]

It should Tina...plenty of warm air under the doghouse!

So here are a couple of  pics of the blocked off EGR, the simplification of the vacuum lines, and all the pretty chrome things...lol!





Sure is pretty!

Actually seems to run quieter now...I was expecting more intake noise and it seems to be less...hmmmmmm...

Gonna hold off on any further adjustments, like the choke and timing, until I see how she runs and what kind of power and fuel economy we get on the way to San Antonio.

Can't wait to see how she performs on the road today!

Gonna keep all the original stuff...took lots of pics so I can put it all back together if I need to later on...but if she runs as well as I think she will, all the original stuff is either getting 86ed or put on eBay in San Antonio!

Kev

[cncsparky]

Good job Kev, I hope it runs good for ya    .  You are doing some of the same things I need to do for mine.  How big is the air cleaner element?   2,3" ?  How much room is there?  I have a leftover 6" air cleaner from my race car days.  Wonder if it would fit mine.

-Tom.

[Oz]

Geeze, the air flow over the engine must be better just from removing that spaghetti mess of vacuum tubes alone.  I remember when Tina had a couple vacuum leaks and I saw the engine compartment under the doghouse.  It looked like someone threw an arm-load of black octopi in there and they just kept breeding!

[gadgetman]

Curious why you didnt replace the egr valve rather than blocking it off ? EGR will actually lower cyl temps and actually improve fuel mileage because it lowers eng vac which reduces load. You can also run higher ignition timing with a egr system.

They really are not bad things to have

Newer vehicles w/o egr valves use variable cam timing to do the same thing.
It is a pretty carb tho

[ClydesdaleKevin]

Decided to keep it all as simple as possible, and 86ed the EGR along with just about every other unneeded vacuum line or possible vacuum leak. 

I'm good at a lot of things, but my mechanical engine skills were all learned on very simple and basic air cooled VW motors.  I got tired of all the headaches associated with the complicated water cooled emissions control smothered engines.

Now this thing is ALMOST as simple as my old Bugs were!

Kev

[ClydesdaleKevin]

Hey Tom.  The air cleaner is 3 inches high and 14 inches in diameter.  I might replace the element with a K&N at a later date, but this is good for now.

Here are a couple of pictures of the OLD way the vacumm lines went.  No leaks or future leaks now!





Kev

[ClydesdaleKevin]

Full power restored, running better than ever before, and getting 8.5 mpg!  Yep, I'm definitely liking the new minimalist vacuum line approach, the axing of the ERG, and my pretty open element air cleaner...lol!

[moonlitcoyote]

Looks pretty Kev


Hubby and I were wondering, since your engine is the same as ours (mostly) how did you know what the vacuum lines went to or what they did before you eliminated them? I mean they were put there for a reason werent they?

[HandyDan]

Not to steal Kevin's reply, this is a diagram on the air cleaner.  It kind of shows where all the lines go.

If you eliminate the stock air cleaner, A.I.R. system, and EGR there is a whole lot of rubber that can be eliminated. 

[moonlitcoyote]

I am terrible at reading those things, I dont even see where the air cleaner is. lol

I have a question that I think would go on this post, my air cleaner has a cable that goes to it from a "choke type" pull/push knob. And from there is moves a metal plate on the air cleaner that allows more air or less air by uncovering screen covered holes in the cleaner housing. Is this a good type of air cleaner, useless, or what? Also any ideas if it should be set for more or less air.

[ClydesdaleKevin]

Sounds like your air cleaner housing has a "divorced choke" type of valve that opens the valve up once the engine warms up...my old one only had a vacuum operated setup that brought in warm air from a hose going to the exhaust manifold.


Kev