[Formula8]

I was working an air cleaner for my Shaker. I have never been happy with my PTFB air cleaner for various reasons. 1) The element provides only 2" of actual filter rather than 3". 2) The distance above the air cleaner base in only 1 3/8". 3) The lid seals against the shaker only providing about a 1/2" slit at the rear for air to enter. IMO, all of these are counterproductive to using a performance intake manifold and Holley to begin with.

My goal was to run a drop base cleaner that will allow a Torker II and spacer. It had to use a full 3" element and had to increase the base to lid distance to at least 2" and preferably more. Here is what I have come up with so far. I need to clean some things up and I think I can make some improvements so I can run a full 1" spacer or RPM but for the most part, what I have accomplishes my goals.

[ta man]

Looks good...is that a AirRaid filter?Do you know what your filter area is?

[Steve C.]

That looks nice. Filter part number ?

According to K&N a larger diameter, short filter will flow more air than a small diameter, tall filter.

K&N formula to determine filter size located here under 'filter selection' .....
http://www.knfilters.com/filter_facts.htm


Out of interest I have talked with a tech rep at K&N about the air flow requirements for my 505cid engine and if the 'small' 9-inch dia x 2.750" tall K&N filter element with the 9" diameter X-Stream filter lid that I'm using is adequate on the street. According to their formula a 505 cubic inch engine at 6000 rpm requires about 745 cfm of air flow. According to him the 9-inch diameter x 2.750" tall ellement with the X-Stream lid I'm using will support about 650 cfm. So he said on the street I'm fine. If I went to the track I'd just remove it.


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[ta man]

K&N's formula is pretty close...according to their formula I need 126 sq inches.I was using a 14 X 3 filter for approximately 131.88 sq inches.In the never ending quest for more power I added a spacer under my carb but had to modify a shaker setup and wound up using a filter 13.5 X 7 , 2.5 inches high about 102.5 sq inches..this small filter actually was too small and would cost about 1.5 mph at the track versus no filter.

[Formula8]

Due to the shape, the surface area is hard to calculate. It is 14" at the base and about 11.5" at the top. The actual media exposure is approx. 3.25 high. My guess would be around 120 sq inches. My larger concern was the proximity of the lid to the base and exposure of the media to cool air from the shaker opening.

[smittyseng]

Originally Posted by Steve C.

That looks nice. Filter part number ?

According to K&N a larger diameter, short filter will flow more air than a small diameter, tall filter.

K&N formula to determine filter size located here under 'filter selection' .....
http://www.knfilters.com/filter_facts.htm


Out of interest I have talked with a tech rep at K&N about the air flow requirements for my 505cid engine and if the 'small' 9-inch dia x 2.750" tall K&N filter element with the 9" diameter X-Stream filter lid that I'm using is adequate on the street. According to their formula a 505 cubic inch engine at 6000 rpm requires about 745 cfm of air flow. According to him the 9-inch diameter x 2.750" tall ellement with the X-Stream lid I'm using will support about 650 cfm. So he said on the street I'm fine. If I went to the track I'd just remove it.


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I tested a 9 x 2.750 K/N element on the dyno vs something less restrictive or with no air cleaner and it lost about 40 hp on my 580 hp 455. I guess that miught be acceptable on the street BUT it also sent afr's pig rich at wot, Smitty
http://forums.maxperformanceinc.com/...d.php?t=681758
I plan on running a edelbrock super Victor under my shaker on my 74 T/A, still haven't decided on what I'm doing for a air cleaner, let us know how this works out, Smitty

[Steve C.]

Excellent information, I always presumed a loss. I don't think I have a choice, in my situation the shaker scoop is molded into my 'glass hood and with my Victor intake carb flange milled down 0.650" all I can get on top of my carb is the 9" diameter x 2.750" tall element with the 9" X-Stream lid. It all sticks up into the inside of the scoop itself with less than 1/2-inch around the sides and the wing-nut is about 3/4" below the scoop top. A 11-inch diameter will not fit !


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[Steve C.]

From the thread Smittyseng linked in his post #6 above. Again, it has some great information presented including his testing involving the 35-40 hp loss with the small 9" diameter x 2.750" tall filter element. It was noted the testing was conducted using the filter element only, there was no testing of this small filter with a filter top installed like the K&N brand X-Stream lid. The use of a filter top will add to the air flow. Comments were made within the thread about testing with a filter top in conjunction with larger diameter filters though, some positive results were noted about the use of the filter top. This subject always draws controversy, some find positive results many do not. Based on reading the numerous tests conducted and reported over the years I'm of the opinion that the specific design of the carburetor used in conjunction with the filter top is important. When I talked with K&N tech they supported comments made that the entrance design on a carburetor has some influence, a design similar to a Holley 'HP' series carb with it's smooth contour does in fact act like their Stub Stack and will help it work with the X-Stream lid. Whereas apparently a carburetor design without a smooth contour (w/ choke tower) and a Q-jet carburetor design doesn't work as well with a X-Stream lid.

If interested, previous thread about K&N X-Stream filter lid test on dyno:
http://forums.performanceyears.com/f...light=X-stream



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[smittyseng]

My motor that I dynoed is fuel injected so I didn't have problems we could see from the xtreme lid, if I had it to do over again I would have stuck the bigger extreme lid on top of the 3 x 9 element just to see what would have happened! The shop that dynoed my engine claims they almost always lose hp when they have used the extreme lids in the past, they feel it disturbs the air flow into the carb, they claimed erratic afr's from this claimed air disturbance affecting the air bleeds in the carb or disrupiting the flow somehow. Keep up the work on making a air cleaner fit , I know that I am going to run something at least 3" tall on my T/A, I'm lucky though, my throttle body is only 1.4" tall vs most carbs at about 3.750 which is going to help me run a super victor intake without too much cobbling. My biggest dillema is going to be getting throttle linkage under the air cleaner with the throttle body being so low, Smitty

[Bigger is Better]

Is that the PTFB kit that you modified or did you get the base/lid from somewhere else? I modified my factory base (took a strip out of it) to make it shorter. I think the big issue is the small clearance over the carb horn which your setup makes better. Looking foward to your results.

[Formula8]

Yes it is the PTFB unit. I emailed Dave with my concerns when I got it but you are correct, my two issues with it was the clearance over the carb horn and the actual exposure of the element to any kind of air. Getting the shaker to fit a bit lower still would be the trifecta but that has proven elusive so far.

I have tried a less severe drop base so the air filter spacer could be eliminated but that would only raise the shaker. I shorter shaker base has been sourced but then the shaker may lower over the filter too much and may contact the filter at the front. I'm going to order another shaker base that is lower and give it a try but the lower shaker base combined with the severe drop base the PTFB cleaner uses is unlikely to work. As that combo seems to be the only one that is going to allow me to run a Performer RPM so I am going to have to try it.

[Larry Navarro]

Keep this in mind.......check the sq. inch area of the shaker opening.

Out of curiosity, did you happen to try a WFO assembly for your application?

[Formula8]

Larry, I did not try your cleaner but I know it works on several cars faster than mine. I am sure it is a good product. I just can't warm up to the small square filter and hardware visable from the driver's seat. I really wanted something that made use of a traditional round filter. From a business perspective, something like this might be something you have more interest in as I don't think I am alone on the square filter thing.

I really think if I could figure out how to get the shaker to set about 1/2" lower and retain the cone filter, I would be really on to something. Right now my shaker base is about 1/2" higher than yours but my air cleaner base has about 1/2" more drop than yours so I have not improved over your assemblies overall height.

I know the square inches of the opening are less than the sq/in of your filter. However, the fiter itself creates a restriction and therefore my belief is the filter must have substantially more area than the opening itself.

[Larry Navarro]

Reading your first and last sentence........it's really not the fact that you don't favor seeing the hardware through the scoop but that you believe the filter is restrictive, even though you say there are cars faster than yours who use the WFO assembly.
With all due respect, i think alot of folks tend to get caught up in the filter issues when it comes to "street cars". Honestly, do you guys driving cars with engines in the 600 plus horsepower really plan on using ALL of that power on the street?? Power like that is best suited for the strip.......where folks would most likely run without an air cleaner in an effort to maximize ET's.
Filter performance has evolved into a "voodoo science" with the perception that more filter area means more flow and more flow means more power. If that were the case, the K&N Xtreme lids would be improving airflow and increasing horsepower but instead does the exact opposite.
I'll bet those who installed the lids, believed that power was increased.......it's the hot rodders mindset that more is better, right?
Anyway, just playing devil's advocate and adding a little food for thought for the sake of discussion.

[Formula8]

Larry, I am not picking a fight over the filter area. I went out of my way to discuss improvements I feel I have made to PTFB's air cleaner and out of respect for you and what I believe is your better product did not draw any comparisons to your assembly until you asked if I had considered it. Many cars have successfully used your cleaner. I chose the PTFB cleaner as it is advertised to do what I needed it to do. Turns out, it falls short and I have fixed the three shortcomings I have identified.

Relative to filter area, the Xtreme lid is a mixed bag and I do not want to wade into that debate outside of I do not believe that it is optimal for my application. You notice I am using a modified traditional lid and that is intentional. I am not saying that my set up will make more power than anyone elses. Well..... I am pretty sure I have a stock PTFB cleaner covered. I believe what you are saying is your product is designed for street vehicles with streetable levels of power and for that application, it appears to be well suited. My feeling is that this is more like a Holley vs. Qjet debate. Both can make plenty of power and have been used successfully. People will have a personal preference and mine is not for a square filter over my carb.

[Steve C.]

"...the K&N Xtreme lids would be improving airflow and increasing horsepower but instead does the exact opposite."

Just to keep the record straight ! Again, this statement is not necessarly correct. In some documented dyno testing with certian carb styles they indicate a K&N filter top did in fact increase in power.


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[Formula8]

Originally Posted by Steve C.

Excellent information, I always presumed a loss. I don't think I have a choice, in my situation the shaker scoop is molded into my 'glass hood and with my Victor intake carb flange milled down 0.650" all I can get on top of my carb is the 9" diameter x 2.750" tall element with the 9" X-Stream lid. It all sticks up into the inside of the scoop itself with less than 1/2-inch around the sides and the wing-nut is about 3/4" below the scoop top. A 11-inch diameter will not fit !


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The shaker has quite a bit more taper in it than I expected. Particularly at the front. I am playing with the idea of one of those offset air cleaner studs which will allow me to move the element and lid slightly to the rear giving me more clearance in the front. If I can gain clearance up there, then I can drop the shaker down a bit which in turn may allow me to run more manifold height.

For your application, my opinion is to keep what you have or look into finding a vendor that advertises their set up to work with a Victor. If the filter is glued into the shaker, then the base is left on the engine, maybe a foam seal that seals the two when the hood is closed will work???? Sorta like a cowl induction hood on a Camaro.

[Steve C.]

I'm curious about how the flow rate is dependent on the pressure difference and the flow resistance of the opening, which itself is dependent primarily on the opening area. Is there little point making precise calculations, since the pressure drop inside the hood scoop itself, which is like a large chamber, have less effect on the in let opening size ? At full engine rpm if a carbuerator is drawing in 800 cfm does the open area of the hood scoop need to be able to pass the same or additional cfm ? What should be the criteria for the inlet opening and plenum interior volume ? And then there is the controversey if the inlet to the scoop itself is under pressure by any ram air effect.



On Air Inlet ("Scoop") Size
http://purplesagetradingpost.com/sum...%20info-1.html

Engine Air Intake Design
http://www.apexspeed.com/forums/showthread.php?t=48954


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[Steve C.]

In my situation K&N has determined my set up is suffciant for my street driving needs and as suggested if I were to go to the track I'd just take of my air cleaner. However with that said, I'm missing a important element here and that is my carb is drawing some hot under hood air since my hood scoop is molded to the hood. Drawing cooler air into the carb will help improve performance a ton ! With that in mind I have thought about fabricating a foam seal for the carb to seal it when the hood is closed. But I've been lazy, that and 600+ hp is enough on the street


The role of cold, air intake system is to feed the engine with cool, denser air with more oxygen and thus improve the performance. The smaller cars may practically lose some power when an induction kit replaces the air filter. It will be challenging to deliver cold air to the engine when the temperature under the Bonnet is very high. In such situations, a direct replacement panel air filter with the standard, air box will be the best choice. Sucking, hot air in from the engine results in power loss.

Cold air discussion:

http://www.torquecars.com/tuning/induction-kits.php

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[ta man]

Originally Posted by Formula8

The shaker has quite a bit more taper in it than I expected. Particularly at the front. I am playing with the idea of one of those offset air cleaner studs which will allow me to move the element and lid slightly to the rear giving me more clearance in the front. If I can gain clearance up there, then I can drop the shaker down a bit which in turn may allow me to run more manifold height.

For your application, my opinion is to keep what you have or look into finding a vendor that advertises their set up to work with a Victor. If the filter is glued into the shaker, then the base is left on the engine, maybe a foam seal that seals the two when the hood is closed will work???? Sorta like a cowl induction hood on a Camaro.

I actually use a flat moroso airpan on my carb with a Edelbrock dual quad filter and top with a Dude scoop.The filter is too small for the track but a step in the right direction.