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Tunnel ram air cleaner

fletcherson

Well-Known Member
i like the hilborn type air cleaners and recently tried one that was described to be basically the same size as all of the mainstream brands. My carbs are inline on a weiand tunnel and are 10.5" apart center to center. The one I tried was advertised for blowers, tunnels up to 9.25" so I asked the seller about it and was told they could be opened up and adjusted to fit. Not so. At least not without major modification to the casting and making a new plate. Do any of you have a similar setup? If so, what cleaner are you running? I have looked at them till I am bug eyed, nothing seems right.
 
hahaha....I really feel your pain on the dual aircleaners....I've fought with just about every dual quad setup ever made over the years....they get some strange spacing sometimes. You can go to the K&N book for reference, I usually get a top thats the way I like it, with the spin on fancy wing nuts. And I look at the chart to get a filter thats at least 3 1/2 " tall. Anyless, and you get restriction.
This next part might make you wince a little, but its what I do.
Get the bottom that came with the dual quad filter that YOU LIKE, Cut out the 2 necks that fit the carbs on the baseplate. I usually measure 2" off the carb throat dia.'s, cut there with the plasma cutter. You now have 2 circular adapters that will sit on the carbs. Go by Tractor Supply OR Lowes, go to their metal rack, get a piece of 12 to 16 ga. sheetmetal, take it home.
Trace the bottom of the cleaner base onto your new metal, and trace out your circular holes that you cut, f at theor you carb adapters, BUT, TRACE THE HOLES 1" smaller the holes you actually cut.
Now, put on the gaskets, the 2 adapters, your newly cut base plate, the small piece of the origional bottom thats felt with the lip that fits the filter.
Twist, hit, bend, eyeball, measure to your hearts content, getting it all straight, level, get all the metal pieces to fit up exact and really as flat as you can get them. Get your MIG and tack things really light, while all this is sitting on your intake. Now, I do this without the fuel in the carbs, but if theres gas in there, be careful. Get a couple of soaking wet rags and stuff them into the carb throats and be syre to cover th bowl vents, too. Do the same for the bowls and the throttlebodys.
Tack it. making sure to get everything good and flat. Tack a little more.
Take it off, I usually TIG it at this point, but if you MIG it, Pulse it. AKA....stitch weld it, tack the whole thing completely around all the cuts, etc.
Put it back on, doublecheck the fit....it shouldn't pull unless you tried to run a bead all the way around it.

Wirebrush it really good, powdercoat it, Paint it black, dark gray, whatever, put all you stuff on and enjoy.
And that new filter you looked up and fits that base....write that Part# down in a little notebook and keep it in your toolbox.
I keep a cheatsheet in my wallet, with the oil, plugs, filter#s, for all my vehicles in there, so if I need to pick something up, its always with me....
 
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They DO MAKE a base that has these adjustable collars that seem to float around so you can adjust them for about any combo, but it HAS these little nuts and bolts that tighten down into the base.
Those little cheapass screws can come loose and get sucked into your motor, so be careful if you go that route. IF you do, just adjust it to fit, tighten everything down good, take it off, weld her up, pull the screws and bolts out, weld the screw holes up, then install.
Make everything a good seal, you don't want sand, dust, or dirt in your motor....
 
You can throw 2 small round filters between the oblong halves you find or make. If you make them, cut the end semicircle to match the filters. If you prefer the oblong filter and get in a tight, sub in the the small round filters to get you by.
I like the two round independent filters out to the max that will clear each other.
 
Here ya go.....
http://www.classicindustries.com/product/mopar/parts/215650.html

I Believe Billet Specialities makes them also....
Thanks, guys. That is what I was going to do, but the one I just returned would have required a lot of carving on the bottom where the base mounts to get it to clear the carb throats and I didn't like the fact that the ends, especially the rear would have no or very little support between the new base and the plenum, or top, or whatever you want to call it and the rear of the base would be very thin behind the carb neck, leaving very little room for the element. The carbs are Holley avenger polished carbs with full metering blocks and fuel bowls and are in line as standard carbs mount, not much gap. 10.5 inches on center. I think most of the cleaners are designed for small blocks with the carbs mounted 90 degree or crossways so the centers are closer. I just need to be able to put my hands on a few variations and measure to find one that allows some wiggle room to work with, enough material to make it strong. I don't want to modify a 2-3 hundred part and create a pos that moves around, etc. I could just throw a couple velocity stacks or the like on it, but it's like the cherry on top. It needs to look good. Nothing is easy, it seems. lol. Oh well, men from boys or whatever. Come spring, there will be some car shows and swap meets and there will be vendors there so I will be able to actually see the parts and find one that I can make work. I was just hoping someone knew of one that was actually made for dual inline carbs, they aren't rare... Speaking of carbs, when I bought the car, the guy had just put two brand new carbs on it and the old ones were laying on the floor, he offered them with the car, so being the pack rat that I am, I grabbed them. I went out to the barn and was looking at them, and they are really in pristine condition, no wear, no corrosion, still have the ink stamped part numbers on the air horns. I looked them up and couldn't believe the result. They are actual Holley factory replacement carbs for 426 hemi cross ram. 780 cfm. I was pretty stoked about that. Not that I will run them on it, but a cool find.
 
If you want a real cherry - build some! I didn't like any of the offerings on my '27. I probably bought and sold 4 different air cleaners (even had a bug catcher!). I finally bit the bullet and made 2 finned air cleaners to fit my mid-rise dual quad setup. Tops are machined from 6" billet aluminum and then machined for the fins. After machining, I filed and sanded them to get a less machined and more cast look. I ended up ceramic-coating them like the intake and valve covers to give a polished aluminum look. The first shot shows one as machined, and one smoothed out. The second is on the car with the rest of the engine candy.


 
The scoop I have on my tunnel ram is 19 7/8" long.... my carbs are 8 3/4 " o.c...... looking underneath I'd say you could get another 1/2" w/o modification... then there's room to trim the mounting plates quite a bit more....This is a generic swap meet chinesedeum scoop I bought about 10 years ago.. IIRC I paid $ 100 then.
dave
 
The scoop I have on my tunnel ram is 19 7/8" long.... my carbs are 8 3/4 " o.c...... looking underneath I'd say you could get another 1/2" w/o modification... then there's room to trim the mounting plates quite a bit more....This is a generic swap meet chinesedeum scoop I bought about 10 years ago.. IIRC I paid $ 100 then.
dave
Cool, I really do like stuff that's different. I'll figure something out. Maybe I will find an old air raid siren and chop on it...
 
Cool, I really do like stuff that's different. I'll figure something out. Maybe I will find an old air raid siren and chop on it...

Anything will work as long as you like it/ make it yourself. Just part of building a Hot Rod as I say. Look back at the early AMBR shows and you will find all sorts of [innovative ideas] that helped in winning.
 
The 10.5 CL is whats gonna give you trouble finding the Hilborn looking unit. Hill Performance makes one that adjusts out to a 9.625 centerline....it will actually go just a tad longer in fact. Most of the others go to about 8.5.
Its simple enough to make a adaptor plate for those things....OR make your own unique one totally from scratch....

Here's a listing of MFG'ers, dig thru these and look around, might find something that will float your boat, so-to-speak. I find this list handy when looking for things like that. Its a good source for digging for parts, maybe Mike would even want to post it....
Anyway, Hope it helps....

http://users.erols.com/srweiss/parts.htm
 
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Also, just a thought, Try
www.racingpowercompany.com
they have all sorts of good stuff there...I Love their adjustable timing tabs....along with the other stuff....
Might try some offset adapters for the Hilborn scoops also....
 
I know this sounds a bit wild, but have any of you ever considered using a fiberglass race car scoop, and using the biggest air cleaner you have fit inside the scoop? Everyone wants big cams, big ports, big runners, big valves, big intakes, big carbs and then they use wee, tiny air cleaners. :confused:

Although I still have an untested theory about using a completely unique scoop design to help establish swirl before air enters the carbs (see where I am going with this, @Screaming Metal?), anything I've ever seen indicates that large volumes of calm air is the best bet, when it comes to making power. Everything the race car ever showed me was that smaller scoop designs would fill with high pressure air, at speed, to a point where air was no longer entering the scoop. We opened up a couple of holes in the base of a scoop and, with no other changes, picked up .7 MPH. Before that, the car was pretty good at sending scoops 20 - 30 feet in the air, when he would step off at the finish line.
 
Hahaha....Mikes totally right! You can only put so much water into a dead end bucket....But with a gas, (breathable air) you can snooker more airflow by venting just a tad off, and letting a wee bit more ram on in!;)
Those NASCARs are still using cowl openings to feed those motors....
Aerodynamics and windtunnel testing shows up some strange and interesting results in various places....
Race teams search for those elusive .02 to .5 results anywhere they can, especially if and when its free.
 
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What I LIKE to do is on a tunnelram, I put a 1/8 alum.plate below the carbs have all the cutouts for the fuellines, linkages, cables, dedenbears, nitrous lines, whatever....in that plate.
Next, I get a econo-dragster scoop, I cut it down in ht. so it will sit on said alum. plate, top of scoop just a touch higher than a normal aircleaner would be. Make L-brackets and are attached to alum. plate.
Now, go get a Big Ole HONKIN' Oval Air cleaner that will go over both carbs, make a single top, and fasten it down Paint the top black, and get a black filter if you can.
Before you fasten your scoop on, drill some 1/8th holes or make notches at the bottom rear of the scoop to drain off water, or condensation that might accumulate....AND to help flow a little extra air that Mike Spoke about....
This will look trick, keep the guys guessing whats under there, and keep all your carbs nice and clean, and keep all that talk going on.
Yea, kinda, sorta the way the Pro-Stockers do their Hood Scoops....But....You never heard it here....:cautious::devilish::sneaky:
 

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