[Joel Koontz]

Is anyone using the Edelbrock Elite 4239 Air Cleaner? If so, any photos?

I have Edelbrock Heads & Valve Covers so it would match well.

Anyone know the base hole spacing/diameters? Is it correct for a 66 Tri-Power?

[Joel Koontz]

I have found some 21" x 10" X 2" Air Cleaner Assemblies that I might be able to modify to work.

I have not found any that have a filter taller than 2" and I would like to use the tallest filter that will fit. If anyone can find a filter taller than 2", in this size, please let me know where.

[Tom Vaught]

I, like John Hargrove, have been running the "Ford 406 Tri-power" style Oval K&N element for years. You can get it made in taller heights.

I purchased a cast alumium blank base and a Ford Thunderbolt ribbed top, took off the Ford emblem and added a GTO fender emblem and get a lot of nice remarks about the set-up.

I can switch the air cleaner between my Holley "6 shooter" Ported Intake and Holley carbs and my 1st gen aluminum Tri-Power Intake with the Rochester carbs.

I got the idea to use the Ford deal from "Big Bill" Klausing many years ago.

Tom V.

When the GTO Nats was in Bloomfield Hills years ago I showed the set up to Chuck Roberts.

[Schurkey]

1. Oiled-gauze filters do a better job of filtering when they have some old dirt on them already. A brand-new, or freshly-cleaned K & N will let more dirt pass through than one with a layer of dirt on it. The worst thing you can do to an oiled-gauze filter is clean it too often.

2. Beyond a certain point, a larger air filter gets you more time-between-cleaning (or replacement) but not more power.

3. The shape of the air cleaner base and top make as much difference as the size of the element, within reason. Ideally, the air cleaner base works like a short velocity stack, directing the air down the venturis smoothly, while the top does not interfere with the carb vents, and does not produce turbulence that interferes with the carb vents.

[Joel Koontz]

I searched and found some taller K&N Filters, but they are about $100 for just the filter. I may end up using one of them, but would be interested in hearing about some cheaper options, if there are any.

Tom(or anyone), do you know where I can get a cast aluminum blank base in 21" X 10" size?

Tom, could you post(or link to) photos of your setup on the Pontiac Carbs?

[Tom Vaught]

Joel, A LOT of the Ford TriPower Air cleaner guys are not out there any more.

Tony Branda http://www.cobranda.com/aircleaners.html still offers a lot of stuff though.

Ribbed tops (no emblem) and blank steel bottoms for the oval Ford air cleaner (filter offered by K&N too).

No name top aluminum (ribbed)

http://www.cobranda.com/nonanaovairc.html

Blank Bottom (steel)

http://store.cobranda.com/blboforovair.html

I bought my stuff years ago when a aluminum bottom was offered.

You could buy the 4 bbl bottom in aluminum and weld up the hole with a aluminum plate and do the holes for the pontiac tri-power though.

http://www.cobranda.com/1x4ovairclbo.html

Tom V.

[b-man]

Use this one for daily performance driving. With the hood closed who'll know the difference?

Take it off and put it in the trunk and put the three little GTO filters on at car shows if you're not into the look.

[lust4speed]

...and just about worth its weight in gold.

[b-man]

As a matter of fact I did have to trade a fair amount of 'gold' for it.

Thought it would be a nice thing to top off the 421 HO.

[Dick Boneske]

The question was asked early on in this post if performance was different with no air cleaners in place. From what I've read, the OP didn't try that obvious test, so we don't know if the air cleaners curtail performance with a Tripower. I have run my GTO with and without the small air cleaners and can feel no difference. Why go through all the effort of oval Ford air cleaners and higher K&N elements when the question has not been answered about no air cleaners?

[android 211]

I have never seen one of those 421 HO air cleaners for sale at a swap meet. I've seen some damaged ones on ebay. I'm sure they cost a few bucks. Car Craft ran a air filter test many years ago swapping different size air cleaners on a big engine on the dyno. There was very little difference between the smallest one and the biggest one. The best air cleaner base is one that arcs into the carb mouth for smooth flow like GM designed them. Flat ones promote tumble and turbulence with less accurate fuel metering.

[b-man]

Removal of the three small air cleaners should be done at the track. Seat of the pants testing really won't tell you if you have a power increase.

A change in ET/MPH at the track would confirm whether removing them had either helped or hurt.

I remember reading about a get together at H-O Racing where they had a Tri-Power 389 on the dyno. After swapping the factory foam filters for a set of K&N filters they saw a 15 HP gain. Never mentioned removing them altogether though.

Running the carbs without the air cleaner bases is probably worse for air flow, but the factory bases don't look like they'd shape the inlet air flow all that well.





The big car air cleaner base shape looks a little better with a small radius, but still pretty flat. The factory Q-jet bases have a very nicely radiused shape at the inlet.

[carbking]

Back in the 1960's, replacing the pie pans with the "ugly" large factory air cleaner was good for a couple of tenths in the 1/4 mile at the track.

Somewhere I read (did not observe this in person) where someone did a back to back using the standard large factory air cleaner and the low restriction factory air cleaner with virtually no change.

As B-man said, probably cannot feel the difference, but certainly measurable.

Jon.

[chrisp]

I can tell you my 64 with pump gas 461 - 66 trips did make more HP & torque without filters vs. the paper ones on chassis dyno rw hp was 428 hp 492 torque without & 423 hp 484 torque with . Paul Spotts was there to do it . I custom made a set-up using the oval steel pan & 3 large base air cleaner bottoms cut & tig welded together with cast polished top . April back to the dyno. will post results

[Tom Vaught]

Originally Posted by android 211

I have never seen one of those 421 HO air cleaners for sale at a swap meet. I've seen some damaged ones on ebay. I'm sure they cost a few bucks. Car Craft ran a air filter test many years ago swapping different size air cleaners on a big engine on the dyno. There was very little difference between the smallest one and the biggest one. The best air cleaner base is one that arcs into the carb mouth for smooth flow like GM designed them. Flat ones promote tumble and turbulence with less accurate fuel metering.

Very Possible with a Round shape Air Cleaner Entrance. That being said, most rectangular or oval air cleaners were designed for the Holley style 2 BBL D-Shaped air inlet to the carb and work very well. The air travels up the base on most carb set-ups and enters the carb by following the radius of the base. The Air does not go thru the filter and do a 90 degree turn down into the carb. All you have to do is look at the dirt on a typical air filter to see that the majority of the dirt is on the lower half of the air cleaner whereas the upper half is typically much cleaner. Course if you have not changed the filters in years once the lower area is blocked with dirt the air has to take the upper less efficient path to the carb.

A deep drop air cleaner base likes a taller air cleaner filter because of the air wanting to travel in a straight line vs go up a 45 degree angle and then turn over 90 degrees to get into the air horn. Drop Base air cleaners solve hood issues but the best flow is the somewhere in between the sharp turn on either side.

Tom V.

ps Pontiac Engineering did a LOT of things right on that big air cleaner.

[wolf]

I tested exactly this question (among some others) the last time I had my '66 GTO on the chassis dyno. I run a ram air pan with my tripower, so with the (paper) filter elements removed, I still had the smooth bell shaped base from the pan in place to help with air entry into the carbs. At the time I didn't think to make a run or 2 without the pan to see how that affected the air entry into the carbs (D'Oh), because it was never something I thought I'd ever do, but now it seems like it would have been bonus information.

Anyway, removing the regular paper filter elements resulted in.....drumroll.... 5 more RWHP on a 410-420 RWHP combination. I doubt you'd ever feel that difference.

Interesting bonus information: there was 7 RWHP lost with the hood closed, and the engine having to breath through just the small stock hood scoop opening, so the early GTO hood scoop is actually a bigger restriction than the small tripower filter elements.

[Tom Vaught]

Originally Posted by wolf

I tested exactly this question (among some others) the last time I had my '66 GTO on the chassis dyno. I run a ram air pan with my tripower, so with the (paper) filter elements removed, I still had the smooth bell shaped base from the pan in place to help with air entry into the carbs. At the time I didn't think to make a run or 2 without the pan to see how that affected the air entry into the carbs (D'Oh), because it was never something I thought I'd ever do, but now it seems like it would have been bonus information.

Anyway, removing the regular paper filter elements resulted in.....drumroll.... 5 more RWHP on a 410-420 RWHP combination. I doubt you'd ever feel that difference.

Interesting bonus information: there was 7 RWHP lost with the hood closed, and the engine having to breath through just the small stock hood scoop opening, so the early GTO hood scoop is actually a bigger restriction than the small tripower filter elements.

Some really good real world testing there. Probably one of the reasons why the later GTO scoops open were not very good either.

Tom V.

[Joel Koontz]

Originally Posted by wolf

"Anyway, removing the regular paper filter elements resulted in.....drumroll.... 5 more RWHP on a 410-420 RWHP combination."

Wow! I would have expected it to make a LOT more difference.

And my new 21 x 10 x 2 filter assembly just arrived today.

I have heard claims of gaining .2 in 1/4 by removing the filters, and claims of gaining 15 HP by changing from stock filters to stock size K&N filters. Your results make those claims seem dubious.

Anyone else have dyno or 1/4 mile tests comparing results, with and without air filters, on a Tri-Power?

[wolf]

Originally Posted by Joel Koontz

Wow! I would have expected it to make a LOT more difference.

And my new 21 x 10 x 2 filter assembly just arrived today.

I have heard claims of gaining .2 in 1/4 by removing the filters, and claims of gaining 15 HP by changing from stock filters to stock size K&N filters. Your results make those claims seem dubious.

Joel,

First off, my testing was done very rigorously to ensure accurate results (I'm more than a bit anal about testing procedures): several runs with each change to ensure consistency, same air/water/oil temperatures, etc. so I'm confident my numbers are real. However, my setup may include another influence that skews the data in this case: I'm not comparing stock air filter lids. Since day one I've had these bell top lids, as I suspected they would breathe better than the stock depressed center lids. Not having stock lids to compare, I haven't been able to verify that assumption, but if some else has credible dyno data with stock lids, we might be able to expand the knowledge on this topic further.

[NeighborsComplaint]

http://www.ebay.com/itm/58-59-60-61-...56b870&vxp=mtr




Available with chrome lid also.

Seller says "2 5/8 CARBS ON 6 " CENTER TO CENTER WE CAN ALSO BUILD THIS TYPE OF AIR CLEANER TO MEET YOUR NEEDS"