Air Cleaner

A relatively stock height engine setup was retained in order to avoid fitment issues with the shaker since I was unwilling to fasten the shaker to the hood as some have done.  This stock style setup included a Tomahawk intake, quadrajet (built by Sean Murphy Induction), and the original 301 shaker.  With all of this there were still clearance problems.  To correct the problem I used a metal shaker base from a ’77 Trans Am and drop air cleaner from Pro-touring F-body.  I went with the EP-401 while using a 1″ air cleaner spacer.  This air cleaner setup looks to be terribly restrictive but it seems to be a fair compromise at the moment.


The faux air inlets of the shaker were cut out to make it functional.  Some honeycomb mesh epoxied in the shaker matches the fender vents.  The drop base shown below is actually the EP-402 which I also tried.  This one however had too much drop and would require a modification of the fuel line to the quadrajet.  If  Pro-touring F-body had setup the EP-402 base for a 2″ filter instead of the supplied 3″ this would be the perfect setup in my opinion.


If I had known earlier that modification would be required for the air cleaner I would have chosen an Edelbrock Performer dual plane intake instead of the Tomahawk.


5 Responses to “Air Cleaner”

  1. I am building my own drop base because I added fuel injection this summer, which required a 7/8″ spacer to be used. Here’s a link of the write up: In my situation, a 7/8″ spacer is not that bad, as the factory Quadrajet used a 1/4″ gasket.

    The Air filter from Pro-touring F-body (PTFB) is actually an Airaid model #801-452. I am going to use this air cleaner, with a 1.25″ drop K&N base and a K&N 11″ filter top #66-1101. Rather than modify a factory air cleaner base, I purchased a 16″ wide pizza pan that is 1.5″ deep. I will be cutting a 11″ hole in the center of the pan to then mount to the bottom of my K&N drop base. This may not work for your situation, but I only need 3/4″ drop, and there’s a good 1/2″ of wiggle room with the shaker. For your notes, Factory drop base is 1-3/4″, with the sides 2.5″. Factory ultimately put the mounting point for the shaker at 3/4″ higher than the carburetor air cleaner mounting height.

    The PTFB model puts extra clearance in their drop, with a 2″ drop, and 2″ high sides. I saw on Max Performance Pontiac forms (previously py forums) that someone made a 1/2″ spacer for between the air cleaner and the base to raise the air cleaner to add a little more air flow.

    I think you may be able to use the K&N filter top to help add a little more air for your setup. I’ve read that the filter tops do not work as well with carburetors, but I think the filter top may help more than hurt with this situation. You may need to cut an edge off of the K&N filter top to prevent it from hitting the shaker, nothing a hacksaw or Dremmel couldn’t fix.

    Blog post of my drop base will be posted in a couple weeks. This past weekend I rebuilt a non-tilt 80 steering column for my Trans Am. It has some special quarks to it due to the turn signal lever being unique to the 79-81 Firebirds only, and most of these years the cars used a tilt column.

  2. Zach says:

    Thanks for turning me on to FiTech by the way. After reading the post on your website a few weeks back I immediately started doing some research. Couldn’t believe the price difference compared to some of the other big players. Mentioned the FiTech setup to a guy at work and the price was enough to put him over the edge as he’s been kicking around the idea of adding efi to his Monte Carlo for a while. He’s working out some gremlins right now but should have it up and running by tomorrow I suspect. This is certainly the route I’m going.
    I think I’m going with a Performer intake and ditch the Tomahawk. I found a carb sealing plate from Weiand on Summit to adapt the square bore throttle body to the spreadbore intake. The plate is only 1/16″ so I think this will put my shaker at nearly the same height as I have now since there is a monster of a gasket under the quadrajet.

    Definitely interested to see your custom air cleaner assembly. I’ll be checking your website for the post. I’m just not crazy about my setup now. Might just go back to the PTFB EP-402 with the filter top you mention since I won’t have the hardline going the quadrajet to worry about soon. It works now but I think it could be much better. Which part number is the K&N base you’re looking at?

  3. Just wanted to leave a comment here regarding the ” This air cleaner setup looks to be terribly restrictive” as the manufacturer I feel that the proper perspective need to be highlighted.
    The Pro-touring F-body has no control over the Airaid filter dimensions and the air cleaner base can’t be made any smaller in diameter or it would not fit over most carburetors or throttle bodies.
    It should be noted that even though there is contact between the filter mesh and the air cleaner base it does not block air flow due to the fact that the air flows between the filter pleats and there is also air flow even at the contact points due to the wire mesh that holds the filter media from making contact.
    FYI in most cases you will not be able to raise the filter 1/2″, it will hit the inside of the scoop.
    Now we do understand some of the concerns and we have finally been able to have ALL the components manufactured to our specs, this includes the air filter there is more clearance between the filter and the drop base.
    Anyone with questions should contact Pro-Touring F-body at or on Face books

  4. Anthony says:

    These designs are fraught with issues.

    No one with any real perspective with regard to air flow would assemble a base/filter/lid configuration in this manner.

    Pro Touring should consult engine air intake professionals and end-users should also rely on the advise of those who do this for a living.

    Never use a lid with media incorporated in it.


  5. Zach says:

    Hi Anthony. Thanks for taking the time to respond. I had previously decided to just leave well enough alone with this issue as I have a number of projects going on at the moment. There is enough debate about this topic that I unfortunately just can’t let it go. I’m kicking around coming up with an evaluation method so we can see the impact of this type of setup and any modifications to it. It will be a while but I’m going to get it done eventually.

    Curious on your background whether you’re ‘in the business’ or an avid hobbyist with real world experience. Would like to hear more details and thoughts you have on the drawbacks of this setup that you alluded to. Also, your comment about never using a lid with ‘media incorporated in it’. I would assume you’re referring to oil based filters? Very interested in your thoughts on this as well.

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