good flowing air cleaner

I would think that the "Chevy L-88" air cleaner would be the best bet for you to try? It is the lowest that I know of and you can play with different height filters to adjust the total height of the assembly.

The base is made to hug a Holley dual feed carb closely. The top tappers down to the outside edges.

Because of it's outside diameter, height of filter, i.e., the surface area available, it provides the lowest possible restriction depending on the element that you use.

https://www.ebay.com/itm/25595...axqCoplfz4FWtk-hyujc

Here is a good illustration of it.

Thank you, I will look into it.

That air cleaner has been copied lots of times by aftermarket manufacturers and while the details often vary from manufacturer to manufacturer, the same concept is continued.

You can't re-invent the wheel. It still needs to be round.

You can't get the base any lower then the L-88 height. The base is "molded" around a Holley dual feed carb.

The top is tapered down and has the minimum internal clearance to reduce flow loss over the top of the carb.

The only variable is going to be what you use for the filter element.

The GM engineering on it is as good as it can be.

The biggest restriction is the distance between top of the carburetor and the lid of the air cleaner… the more distance the better the airflow! Straight down would be perfect!

I do like to have the spacer between the intake manifold and the carburetor because it insulates some of the heat… but there is a price to pay… I am thinking how to get the most space between the carb and the top of the air cleaner on my new engine built… ! Maybe milling the top of the intake down and then putting the spacer/insulator on top without increasing the height…

wheels are still turning 🤪

you may already saw this:

https://www.dailymotion.com/video/x693421

I use a variation of this proform model. A takeoff on the classic and effective Moroso design. It was easy to polish up and looks right.

Good clearance where the decklid comes down and it will fit under the engine screen, though I don't run one.

https://www.summitracing.com/parts/pro-141-691

They do offer different drop heights, but probably not as snug a fit as Dougs suggestion.

It isn't just the air cleaner, it is the intake manifold as well, but the criteria given as I understand it is for a street car and to fit under the screen?

A tunnel ram with unlimited space over the carbs and open velocity stacks is the least restrictive.

You could lower the engine like the Cobra Daytonna Coupes did as well?

There is compromise with everything. For the specific application you need to determine the best combination of compromises.

The Blue Thunder copy of the Shelby intake manifold is not the best intake selection available.

The question has come up multiple times about how much clearance is needed above the carb for minimal air flow restriction.

I did a lot of experimentation with the Weber 48ida "eight stack" system. The number there that comes up which seems to be readily accepted is a number equal to or similar to the od of the velocity stack. So that number is 2" to 2.25" of clearance over the top of the carb.

In the case of the L-88 air cleaner, that is what you wind up with in the stock configuration. The clearance is right on that number since if you look at the detail, the top tappers up like the "Big Top" of a Circus tent.

It is "old school" but the design works.

@panteradoug posted:

It isn't just the air cleaner, it is the intake manifold as well, but the criteria given as I understand it is for a street car and to fit under the screen?

A tunnel ram with unlimited space over the carbs and open velocity stacks is the least restrictive.

You could lower the engine like the Cobra Daytonna Coupes did as well?

There is compromise with everything. For the specific application you need to determine the best combination of compromises.

The Blue Thunder copy of the Shelby intake manifold is not the best intake selection available.

Lowering the engine.. & transaxle.. I don’t think so… LOL (can’t lean it because of distributor against firewall)

my thinking goes in the direction of remote air filter… somewhere in the right side down low… just have a bump for the turn into the carburetor with 5” tube..and get larger in diameter once the crap is cleared… pretty much like injected engines carry the air.. it’s just the turn into the carb that has to be well thought out!

Side effect.. colder air intake!!!

@panteradoug posted:

It isn't just the air cleaner, it is the intake manifold as well, but the criteria given as I understand it is for a street car and to fit under the screen?

A tunnel ram with unlimited space over the carbs and open velocity stacks is the least restrictive.

You could lower the engine like the Cobra Daytonna Coupes did as well?

There is compromise with everything. For the specific application you need to determine the best combination of compromises.

The Blue Thunder copy of the Shelby intake manifold is not the best intake selection available.

Your assumption is correct. Street car, with stock looking engine.

I don't want to change the position of the engine, that can of worms is a bit too much for me.

What would be your recommendation for an intake manifold with 4V heads?

I already have a 1 inch dropped base plate, which was on the car when I got it. It had a cheap Summit top, which I couldn't stand. With the flat Aluminium Top, with "Pantera" on it, it hit the deck lid.

With a 1 1/2 drop base and a 3 inch filter it worked, but then bad things happened (as seen in the first post).

@GeorgS posted:

Your assumption is correct. Street car, with stock looking engine.

I don't want to change the position of the engine, that can of worms is a bit too much for me.

What would be your recommendation for an intake manifold with 4V heads?

I already have a 1 inch dropped base plate, which was on the car when I got it. It had a cheap Summit top, which I couldn't stand. With the flat Aluminium Top, with "Pantera" on it, it hit the deck lid.

With a 1 1/2 drop base and a 3 inch filter it worked, but then bad things happened (as seen in the first post).

For me, the best performing intake with the least issues was the Edelbrock Torker.  It is a little taller then the stock Ford intake but has much better off idle response.

The Blue Thunder is a copy of the Shelby intake. I used the Shelby intake and compared to the Torker was disappointing.

The Shelby has been out of production for 50 years and I can't speak to how close the Blue Thunder is to it but my impression was that it may be the best intake for a 351c with an automatic transmission.

In all cases I found that a vacuum secondary carb was a significant hindrance and wound up using a Holley 4179, 750cfm with mechanical secondaries.

That combination right there would be the issue for an automatic transmissioned car, but in my view the preferred combination for a manual transmission and a performance camshaft is the Torker.

It would be fair to state that I run a solid lifter camshaft. Then and now. In my view if you are running a hydraulic lifter camshaft, even a hydraulic roller, you are just pretending to have a high performance engine no matter who attempts to convince you otherwise. It is just not going to put you into the rpm range where the Cleveland engines out perform just about everything else.

I did run two of the Ford Motorsport "aftermarket" intakes using the A3 aluminum high port heads.

I used the tall spider single 4v and the Torker style. I found the tall spider just a waste of time for my application. That one is just intended for constant rpm use in the 7,000 rpm and above range. That is where it will show maybe 25 more hp but the A341 "Torker type" was similar to the Edelbrock for the iron 4v heads and the better choice.

I long ago (25-30 years) went to an 8 stack with the A3 heads. That is where the car is now. So single 4v intake systems for me are old news. They are just not in the same ball park as an 8 stack regardless of what you may see on Dyno Masters

You likely will run into contrasting opinions but the Pantera tends to be a unique vehicle in that the same 351C in a Mustang has different requirements in a Pantera.

What you likely are approaching building in a Pantera is something on the order of a Group 3 or Group 4 car, or something in between.

It all depends on how you intend to run the car? You can run a 7 liter version of the engine but have rpm limits of 6,000 or under or run something like what DT ran in the Comp cars way back.

It is this difficulty in conceiving exactly what you want the engine and car to be that seems to be the issue for many? YOU need to have the focus and make the determinations. As such there probably is no way to avoid making mistakes in judgement. It is all part of the game.

I do have sympathy towards that situation. It reminds me of my own mistakes.

"Do not remind me of my own failures. I have not forgotten them." - Jackson Brown.

@LeMans850i posted:

Lowering the engine.. & transaxle.. I don’t think so… LOL (can’t lean it because of distributor against firewall)

my thinking goes in the direction of remote air filter… somewhere in the right side down low… just have a bump for the turn into the carburetor with 5” tube..and get larger in diameter once the crap is cleared… pretty much like injected engines carry the air.. it’s just the turn into the carb that has to be well thought out!

Side effect.. colder air intake!!!

For EFI the long hose isn't significant. For carbs it is.

It is as if there is some sort of "coefficient of friction" kind of factor on the tube that makes the length of the tube restrictive at some point.

You get as much cold air into the engine compartment as anything else by using the "sugar scoop" on the decklid.

That was an idea developed over at Ferrari, happens to work, and was "stolen" by Detomaso.

Form follows function even if you don't like the looks. Everyone's a critic. Not every song is played the way you would do it, but you listen to it anyway?

@panteradoug posted:

For EFI the long hose isn't significant. For carbs it is.

There is some sort of coefficient of friction on the tube that makes the length …

Can you (or anyone else) explain… because I can not figure out the difference….

… in an engine where you would have the carburetor attached with a tube to the cylinder (motorcycle) and you would increase the length of this intake manifold you would at some point experience the problem of keeping the fuel suspended in the air.. while velocity stack (carb and injected) on the breathing side increases the fuel/air charge in the cylinder (column of air keeps pushing) This is not what I’m going for… I’m looking for pur air delivery!

i just don’t see the difference between EFI and Carburetor in regards to air only delivery!
yes, there is a boundary layer inside the tube that doesn’t move because of friction caused by the tube surface but add 1/2” to diameter should take care of that..

Looking at the EFI setup the hoses are anything but “streamlined”

The original air cleaner has a snorkel on it for about 12 inches long…

would a 4 inch diameter tube 30 inches long be more restrictive?

I would like to know….

it’s not about “everyone is a critic “ or the song thing… but just going for “because I say so” doesn’t count…

Thank you for  your insights Doug.

My Pantera is a narrow body without any attempts to get it to a Group 3, 4 or anything like that. But you are right, I know several Panteras here in Germany that are all widebodies, with racing seats and uncomfortable suspension. One of these is the only other Pantera I ever drove, it has a stockish 351C with closed chamber heads, a Torker and a 750 Holley double pumper and I wasn't impressed at all. I understand that with enough duration and overlap with a mechanical cam, you need a mechanical carb, if it is a Holley Double Pumper or a Weber 8 Stack, but my relatively mild engine doesn't need that.

Where I disagree is the Intake. Personally I don't like the Torker, the modern single planes like the CHI make the turn towards the heads early to let the mixture go straight towards the inlet on all 8 cylinders, while the older intakes like the Torker have 4 cylinders that go straight and 4 that have a turn directly in front of the head.

I am surprised that other don't have the same problems with the air cleaner assemblies.

As some know, I attacked the height problem by lowering the entire engine/ZF 1-1/2". I sectioned the lower motor-mounts and redrilled the rear ZF mount tabs. With only that much, the rear crossmember still clears an Aviaid oil pan and the shifter & all the lines still fit as-stock. I did it mostly due to the taller SVO A-3 intake manifold, but a 3" thick air cleaner element is now not an issue either.

@LeMans850i posted:

Can you (or anyone else) explain… because I can not figure out the difference….

… in an engine where you would have the carburetor attached with a tube to the cylinder (motorcycle) and you would increase the length of this intake manifold you would at some point experience the problem of keeping the fuel suspended in the air.. while velocity stack (carb and injected) on the breathing side increases the fuel/air charge in the cylinder (column of air keeps pushing) This is not what I’m going for… I’m looking for pur air delivery!

i just don’t see the difference between EFI and Carburetor in regards to air only delivery!
yes, there is a boundary layer inside the tube that doesn’t move because of friction caused by the tube surface but add 1/2” to diameter should take care of that..

Looking at the EFI setup the hoses are anything but “streamlined”

The original air cleaner has a snorkel on it for about 12 inches long…

would a 4 inch diameter tube 30 inches long be more restrictive?

I would like to know….

it’s not about “everyone is a critic “ or the song thing… but just going for “because I say so” doesn’t count…

I don't really know why but with carbs a very long air tube becomes an issue at some point OR what that length may be but it may be that when you extend the air intake length at some points it effects the Venturi principle? Maybe loss of critical velocity through the venturi? I don't know but usually in a car there isn't enough room to make the tube too long so it isn't normally a problem?

I do remember the '64 Ford Fairlanes with the High Rise 427's with their long 4" diameter air tubes that went under the front bumper. Since I never ran that setup, I don't know what issues if any that it caused? Perhaps because it was intended for racing, the useful rpm range of the engine created enough velocity through the hoses? Back then a 7,000 rpm engine was a big deal.

Some of the '60s GM cars like the Olds W-30s used the long 4" hoses like that also. They looked a lot like the insulated flexible air conditioning hoses that are used now in houses.

I've always seen the preferred induction solution as a short velocity stack on the carbs themselves like you would run on Weber 48ida's and as close to "out of the engine compartment air" as possible.

Think of Bill Thomas' Cheeta with the carbs themselves sticking right through the hood with open velocity stack on the carbs.

I would think that you need to state things in mathematical terms or equations like Albert Einstein did to see the critical factor in the equation? I can't write the equation. My head doesn't work that way. You would probably have to get a carb engineer from someone like Holley to explain anything.

I just know the empirical method. Build it until it works.

I do also know that what was referred to in the 1960's as "cold ram air induction" has limitations because the ducting at some point becomes restrictive. It has also been pretty much proven that there was little to no "ram air effect". The benefit was actually from cooler air being brought in from outside the hot engine compartment but if you notice where the most effective locations of cold air was, a "hood scoop" directly over the carbs?

Seemingly most solutions have advantages and disadvantages. Mid-engined cars are "land-locked" for cold air. The Pantera is no exception.

You probably have seen the "snorkel" that sticks up over the back of the roof and plumbs "outside" air to the carb/s on many race cars? That really is what the "sugar scoop" is doing but some find it not an "aesthetically pleasing" solution.

To me, the term "Form follows function" is an Architectural term for justifying an ugly building or solution?

The Pantera "Bat Ears", i.e., the side scoops that replace the rear 1/4 glass, stick up like that because the wind tunnel testing showed they had to reach up into the air flow and below that point, there was dead air.

One of my customers/clients is a "high performance aircraft engineer". To put it bluntly, not only do we not get along, we don't even like each other. Basically because my interests are in cars and to him that is as low on the evolutionary ladder as an ameba?

With fuel injection the Venturi principle is not involved but how the shot of fuel splashes to atomize the fuel near the intake valve is.

There with EFI the cpu adjusts for the temp of the air being taken in so supplying the induction with colder air doesn't matter much since the computuer adjust the fuel flow to the injectors to maximize the power according to the A/F ratio menu that it is reading from.

Nothing to be gained from colder air there.

...oh, and for me posting isn't a "because I said so" thing. It certainly isn't intended as a lecturing. It is just posting about the good, the bad and the ugly that I have done. If it helps anyone at all, even a little, fine. If not, just consider it the ravings of a maniacal, disillusioned individual that comes here for therapeutic reasons and ignore it.

My wife ignores me all of the time...well most of the time anyway. So that ground has already been laid. Literally.

Actually she thinks that I need hearing aids. I don't think yet that she realizes I just don't pay any attention to her?

@bosswrench posted:

As some know, I attacked the height problem by lowering the entire engine/ZF 1-1/2". I sectioned the lower motor-mounts and redrilled the rear ZF mount tabs. With only that much, the rear crossmember still clears an Aviaid oil pan and the shifter & all the lines still fit as-stock. I did it mostly due to the taller SVO A-3 intake manifold, but a 3" thick air cleaner element is now not an issue either.

@GeorgS posted:

Thank you for  your insights Doug.

My Pantera is a narrow body without any attempts to get it to a Group 3, 4 or anything like that. But you are right, I know several Panteras here in Germany that are all widebodies, with racing seats and uncomfortable suspension. One of these is the only other Pantera I ever drove, it has a stockish 351C with closed chamber heads, a Torker and a 750 Holley double pumper and I wasn't impressed at all. I understand that with enough duration and overlap with a mechanical cam, you need a mechanical carb, if it is a Holley Double Pumper or a Weber 8 Stack, but my relatively mild engine doesn't need that.

Where I disagree is the Intake. Personally I don't like the Torker, the modern single planes like the CHI make the turn towards the heads early to let the mixture go straight towards the inlet on all 8 cylinders, while the older intakes like the Torker have 4 cylinders that go straight and 4 that have a turn directly in front of the head.

I am surprised that other don't have the same problems with the air cleaner assemblies.

I haven't tried any of the new tech inductions such as the CHI. Who am I to question their tech and efforts?

I can only share what I did and much of that is now ancient technology.

Many here have or are using the Blue Thunder. I haven't but I used the Shelby version that theoretically the Blue Thunder derives from?

My experiences are delineated in my previous posts. No need to repeat that.

There have been a few mostly racing Panteras that have used the Bat Ear scoops and ducted the air cleaner to them.

Apparently that works but takes up a lot of room in the engine compartment and blocks your rear vision.

Others have mentioned ducting to the bottom of the car as workable.

I have a pair of "clear molded plexiglass" Bat Ear scoops that you can see through. Exactly how much cool air, if any, they are supplying is anyone's guess but they look cool and you can see through them and they don't block the rear vision.

Actually I am still waiting for them to blow off? I'm not going fast enough for that yet.

I remember Gary Hall's blowing off of his race car. You can't just hang'em on the window gaskets. You need to fasten them into the sheet metal!

Necessity is the Mother of invention. Go for it. You don't need anyone's approval here for your solution. Solving the problem well is an awfully fun project.

@panteradoug … Last thing I would is ignore you!

I just would like to pick somebody else’s brain… it’s easy to just think and come up with some idea and make it… but getting the inside of somebody else is very helpful… Another point of view!

I appreciate your response very much!

Dog bone dimensions:

2.5” carb flange to top

1.5” x 4.5” narrow and skinniest crossing to filter (per side)

@panteradoug posted:

I have a pair of "clear molded plexiglass" Bat Ear scoops that you can see through. Exactly how much cool air, if any, they are supplying is anyone's guess but they look cool and you can see through them and they don't block the rear vision.

Actually I am still waiting for them to blow off? I'm not going fast enough for that yet.

I remember Gary Hall's blowing off of his race car. You can't just hang'em on the window gaskets. You need to fasten them into the sheet metal!

My guess would be that they do shovel air in if they blow off…. If they would be in dead air   nothing would happen…

I once forgot my pump out pump for the floats of my Amphibious airplane on top of the float and I took off at the airport and I looked down through the window and the pump which is made out of plastic tubing, 24 inches long maybe weight 1 pound was laying on top of the float and I was flying about 90 miles an hour and it did not care (or fly off)  I made the best and  softest water landing I ever did and retrieved my pump..

Dead air is dead air…

@LeMans850i posted:

@panteradoug … Last thing I would is ignore you!

I just would like to pick somebody else’s brain… it’s easy to just think and come up with some idea and make it… but getting the inside of somebody else is very helpful… Another point of view!

I appreciate your response very much!

Well even being a negative barometer has it's values.

There are lots of air cleaners that look like they work but don't.

I would also prefer just to build it rather then design it.

An interesting detail about that L88 air cleaner. If you run without it, the engine goes from 500hp to about 600.

… no free lunch ☹️

"An interesting detail about that L88 air cleaner. If you run without it, the engine goes from 500hp to about 600."

I guess then it isn't the best choice after all...

https://www.summitracing.com/parts/sum-239525b

I will try this one and turn it 90°, so that it sits in front of the deck lid. I also bought 2 spacers (1/2 and 3/4 inch) between air filter and carb.

I'll let you know what the afr gauge says and if I am able to see traffic behind through the mirror afterwards.

@GeorgS posted:

"An interesting detail about that L88 air cleaner. If you run without it, the engine goes from 500hp to about 600."

I guess then it isn't the best choice after all...

https://www.summitracing.com/parts/sum-239525b

I will try this one and turn it 90°, so that it sits in front of the deck lid. I also bought 2 spacers (1/2 and 3/4 inch) between air filter and carb.

I'll let you know what the afr gauge says and if I am able to see traffic behind through the mirror afterwards.

I think that the L88 air cleaner is the best an air cleaner can be given the same criteria to solve? It is just the nature of an air filter to reduce the potential of the carburetor.

The best of the air filters kills 80 to 100 hp of a big block.

ALL of them seem to act as an RPM limiter at around 5,000 rpm's.

Even the screens across a velocity stack reduce the flow and therefore the total power potential. Why do you think race cars run without filters?

I am VERY SURE either that "dog bone" or one very similar was dyno tested and found to be very restrictive even without a filter? It was some time ago that the test was done? Probably 15 years ago or so? I do not remember who did the testing?

I posted this before but will post again.  Good flowing and "fits under the stock mesh" don't have a real intersection.  Engine Masters air cleaner testing provides good info.

https://www.facebook.com/watch/?v=153247265330893

Here is the 63-4 Ford Fairlane 427. This was the air cleaner solution.

I stand corrected. Those hoses are a lot bigger then 4". 6" maybe?

Those hoses run to inner side of the dual headlight configuration. As I recall they are in the vicinity of 48" long each?

That really is answering that question to a good extent. It shows whoever did the development on that induction that they looked at lowering the restriction to the carbs.

I believe that there are filter elements inside of the housing but I just don't remember for sure that detail?

That is a Factory Ford race car that could legally be driven on the street.

I would strongly suspect that they were run mostly without the air cleaner/filter elements.

That engine was always thought to be 600hp.

Induction was not it's limitation with 2.19 intakes,  dual Holley 715cfm carbs and extra tall intake runners. The exhaust ports were very restrictive. All FE exhaust ports are.

I remember many of them "blowing up" at the drag races since 7,000 rpm's was the limit of valve spring technology at the time and they were launching at 8,000-ish rpm.

The valves were also early sixties "high tech light weight design" with the valve stems hollow and filled with sodium to lighten the weight of the valves. Many of those would break and drop the head of the valve into the cylinder.

Today titanium is the material of choice for valves but the stems wear much faster then the normal chromium-steel alloys and at $150 per valve don't give any longevity.

The W30 version of the Olds 442 is VERY SIMILAR to this design. I don't have any pictures handy of those though.

Here is a link to a similar discussion with pictures.

https://www.chevelles.com/thre...s-for-carbs.1137208/

This is similar to what you are suggesting your solution should be. It is very comprehensive and is giving me migraines trying to  crash all the alternatives in? Don't overdose on it!

Here is another solution that some of the Pontiac Fiero people came up with... and here is a previous discussion here.

https://pantera.infopop.cc/top...take-i-am-going-down

If nothing else, for me this is a fun discussion. I always like to see the solution others have come up with.