Air filter restriction Indy 440-25 intake

[malex]

Having recently completed my 64 Plymouth build I'm wondering about the amount of air filter restriction that likely exists. Due to space under the 4" scoop the largest air filter I can use is a 2x9 inch.
My combination is: 526 cubic inch, Edelbrock Victor Max Wedge Heads, Comp solid roller, the 440-25 Indy intake with 2-750 Edelbrocks, TTI 2" through 3" Dynomax.
I'm wondering what experience you guys might have on this topic? If I'm out for a cruise and get on it hard will these filters choke this big stroker out and how bad?

 

[440+6]

This might help
http://www.knfilters.com/universal/x-stream.htm

 

[68 HEMI GTS]

i run the extremes on my hemi. absolutely no difference in et with or without them.

 

[malex]

i run the extremes on my hemi. absolutely no difference in et with or without them.

Thanks very much for the info on the extremes. Do you happen to know your measurement from the base plate that the air filter sits on to the top of the extreme?

 

[dvw]

A guy I race N/SS with slows his car down with your filters. But on the street I wouldn't worry about it. I've always though about some type of filter in the hood scoop. Your engine looks like it is about 1" higher than mine. Nice to see it rolling.
Doug

 

[malex]

A guy I race N/SS with slows his car down with your filters. But on the street I wouldn't worry about it. I've always though about some type of filter in the hood scoop. Your engine looks like it is about 1" higher than mine. Nice to see it rolling.
Doug

Hi Doug. I was hoping you would comment and thanks for your input! I have the newer K frame in the Plymouth and solid mounts. That perhaps is the difference in height.
Yeah these air filters are good enough for the street like you say and they'll certainly come off once I get to the track. Curious, do you happen to recall how much effect those filters have on your friends car? Quite a concept on slowing a car down too.
Thanks,
Mike.

 

[383man]

I run this 9" x 2" Spectre air filter unit I bought from Jegs on my 493 on the street. It works fine with no problems. I dont street race but sometimes I will lay into it a little to wind it out and it seems to be fine. I never compared racing with it on or off but it dont foul plugs and responds just as good on the street by the seat of the pants feel as it does at the track. I went to this smaller 9" because the bigger 14" unit was holding more heat over the fuel bowls and I wanted to get as much heat away from the carbs as I could running this cheap pump gas that will boil in the fuel bowls if it gets enough heat at the carb. I have seen fuel boil on cars that were running only 190 on the temp gauge and not overheating at all but this pump gas with the ethanal in it will boil around 190 to 200 I have heard and when it does it will cause the car to flood. But this works good on the street and I like the kind with the top like this and the ones 68 Hemi GTS uses as they pull air through the top also. And you can just take it off at the track if you dont want to race with it on. Ron

 

[dvw]

Hi Doug. I was hoping you would comment and thanks for your input! I have the newer K frame in the Plymouth and solid mounts. That perhaps is the difference in height.
Yeah these air filters are good enough for the street like you say and they'll certainly come off once I get to the track. Curious, do you happen to recall how much effect those filters have on your friends car? Quite a concept on slowing a car down too.
Thanks,
Mike.

It slows it about 2 tenths depending on weather. My motor is about 3/4" higher than stock. Same intake/carbs. The front carb air horn base is level with the hood. You can see the choke tower in the picture.
Doug

 

[Budnicks]

could you get some sort of drop base air cleaner base type of set up ??
& still fit the inline carbs/carters/Eddys ??

not sure who or what co. would make them,
but probably out there somewhere, just need to look

just run short-velocity stacks at the track seal the hood-scoop to the carbs too

I like the dvw idea of the filter in-front of the scoop too,
especially with the carbs sealed to the hood-scoop

 

[Shorthorse]

Found this on K&N's site under Filter Selection.

http://www.knfilters.com/filter_facts.htm#SELECT

Use the formula below to compute the minimum size filter required for your particular application. The usable portion of the filter is called the EFFECTIVE FILTERING AREA which is determined by multiplying the diameter of the filter times Pi (3.1416) times the height of the air filter in inches, then subtracting .75-inch. We subtract .75-inch to compensate for the rubber seals on each end of the element and the filter material near them since very little air flows through this area.

A=(CID X RPM) / 20,839
A = effective filtering area
CID = cubic inch displacement
RPM = revolutions per minute
at maximum power

I ran the numbers (X2 filters) and just used/guessed 5500 rpm's. If I did it correctly (big if), you're a little under on the air flow. Perhaps the filter tops would bring it more in line.

- - - Updated - - -

Doug,
If you ever come up with a way to filter the scoop, please share it. The only time it really bothers me is those few tracks that have the staging lanes directly behind the burnout box but its been a while. Or, the track is trying to hurry up the rounds and they wave you early but at those tracks I won't move until the guy in front of me is done with his burnout.

 

[malex]

It slows it about 2 tenths depending on weather. My motor is about 3/4" higher than stock. Same intake/carbs. The front carb air horn base is level with the hood. You can see the choke tower in the picture.
Doug

Doug, do you have the original K frame in yours? It does appear I'm about an inch higher than you. My K frame is out of a 69 B body I believe. I checked my solid mount brackets and I see where those could be lower by about 3/4". I have about an inch between my pan and draglink right now.

- - - Updated - - -

could you get some sort of drop base air cleaner base type of set up ??
& still fit the inline carbs/carters/Eddys ??

not sure who or what co. would make them,
but probably out there somewhere, just need to look

just run short-velocity stacks at the track seal the hood-scoop to the carbs too

I like the dvw idea of the filter in-front of the scoop too,
especially with the carbs sealed to the hood-scoop

Thanks for the input Budnicks. With the Eddy carb accelerator pump lever and this intake the 9" filter is max diameter. So I can't go any lower with the base plates. I see where I can get some additional room though with different or by modifying my mount brackets so that's first on the to do list.
I bought my intake used and it came with a plenum to hood plate. My hood hole is larger than this plate but it is exactly what you're referring to and where I'm heading.

 

[dvw]

My K frame is 64 6 cylinder, but the motor is on a plate. I compared my engine height to my Buddy's 65 Belvedere (440) and a 70 Coronet R/T (440). Both are stock style installs. Both are 3/4"-1" lower than mine. I run the same style air pan pictured. It has holes for the accelerator pumps.
Doug

 

[Hemi Rebel]

Try connecting a vacuum gauge to ported vacuum. And drive it with and without the filters. Compare the 2 readings. Or maybe get the gauge connected to the air cleaner to measure vacuum on the inside of the filter and see if it pulls a vacuum inside the filter under load. Then you know you have a major filter restricition issue

 

[Mike Gaines]

Restricted Air Flow or not.....THAT IS ONE BEAUTIFUL SETUP.....WOW !!!! You should really be proud of that build...

Side Note: You will NOT be able to open that beast up on the highway anyway...so what difference does it make...when you take it to the drag strip just take off the air cleaners.

 

[malex]

Restricted Air Flow or not.....THAT IS ONE BEAUTIFUL SETUP.....WOW !!!! You should really be proud of that build...

Side Note: You will NOT be able to open that beast up on the highway anyway...so what difference does it make...when you take it to the drag strip just take off the air cleaners.

Mike, thank you for the compliment on the Plymouth, it is appreciated. The Plymouth is fresh so it's at its best. But you're right, air cleaners off when it's time to make a pass, problem solved! Mike, I also have to research back to see how your new engine performed, somehow I missed it.

There has been great information on this thread shared by the members. Thanks Guys! But for example: 68 Hemi GTS uses the K&N extremes and elements and there is no change in performance with or without air cleaners. Can't beat that.
Doug mentioned that a friend of his loses about 2 tenths when using the spectre air filters like I have and he noticed that his engine sits almost an inch lower than mine. Just on these 2 comments alone I need to get my motor down and then switch to K&Ns with the extremes up top.

I'll also be fabricating a plenum to seal the hood to the carbs like Doug does and I'll make it so that I can run with or without filters; sort of along the lines to Shorthorse's comment about filtering. If I can get to the point where the Plymouth runs the same with or without filters I'll be leaving them on. I'll share my findings when I get to that point.
Thanks,
Mike.

 

[68 HEMI GTS]

Thanks very much for the info on the extremes. Do you happen to know your measurement from the base plate that the air filter sits on to the top of the extreme?

i'll measure them tonight, they look to be about the same dimensions as yours.

 

[68 HEMI GTS]

roughly 3.75 in

 

[malex]

roughly 3.75 in

Thank you very much for the measurement 68. It helps me with the plan. On another note I took the Plymouth for a drive to the weigh scales today on the highway. 3,460 lbs in complete form with the passenger's door bar in place and a full tank of gas, less air filters. I did get on it and it pulled to 6,500 no problem. It felt much better than with the filters.