Least restrictive air cleaner
- Thread starter Poppas409
- Start date
https://www.hotrod.com/articles/inside-scoop-mike-finnegans-gasser-blasphemi-2-0/
High end motor build....... but 20 ftlbs more than no filter on dyno
Walker performance filtration
High end motor build....... but 20 ftlbs more than no filter on dyno
Walker performance filtration
409 lid, NOS HEMI air filter (flat hood car). Spun aluminum hemi base with the holes moved to match the center to center for 409 2x4 ( hemi 2x4 was different). Intake was square port 2x4 that I ground every identification off possible, same spacing as a 2x4 409.
Did you use one of those open element filters that in OEM boxes goes for about $500!
Robert
That isn't really true. The most performance is achieved when the right amount of air, at the right speed in the right area, with as little disturbance as possible, with a fuel/air mix that is as homogenized as possible will yield the best performance. Simply thinking in terms of gross air flow as the biggest determining factor for performance is missing the big picture. The test you posted really does not tell us anything because the base and lid are different for each test. There is no way to say what was the cause of the hp gain or loss. Many people have dynoed the filter top filters while keeping the same base. The hp losses can be significant and tests that showed a gain only showed a very small gain. A hole will pull air in from the sides. Somehow the lid screws with that.
this has turned into an interesting read for me based on the original question. I’ll enjoy the final outcome of it for sure. Interesting as I don’t think the air filter will be for an all out race car or a restored show car either. So.... Show cars has made for them a 5 inch 62 style filter using a GM manifold. Might be his best choice to enjoy this season’s drives
Not down grading Jim’s units
but I don’t think the owner has the waiting time Robert
The different air cleaner tops are common styles used by many people. This video covers the differences in performance between different styles and that is it. Big hole, big air isn't the simplicity of the thinking but free flowing air unrestricted to the venturis of the carb is the best performance rule. I'm having a hard time finding anyone that has suffered performance from one of these air cleaner tops. Does anyone have any links discussing this because I've been searching for a good part of the day and haven't found a single one. I can't image how air with a straight shot into the carb would suffer performance but maybe there is something creating a vortex? I don't like the idea of keeping the single wingnut in the middle of the carb when that itself is a restriction.
GREAT! Give me something else to obsess about! 
I stuffed these on my carbs because they have proven to help Edlebock carbs but I think I might be better off milling the carb chokes off.
^^^ That's a good start for most. 
https://www.speed-talk.com/forum/viewtopic.php?t=9032&start=45
https://www.speed-talk.com/forum/viewtopic.php?t=7285&start=15
https://www.speed-talk.com/forum/viewtopic.php?t=31394
Have fun!
Free flowing air to the Venturi is a great thing as long as it doesn’t upset the vents, air bleeds, or booster. Simple right? This stuff can really drive you crazy. Just keep reading and reading some more. Then go out and try what you learned. Eventually you’ll be as confused as I am!!
Oh and don’t bother removing the choke horn on the edelbrock/afb unless you are really bored. Out of all the things you can do to improve flow, that shows the least gain. Practically nothing.
https://www.speed-talk.com/forum/viewtopic.php?t=7285&start=15
https://www.speed-talk.com/forum/viewtopic.php?t=31394
Have fun!
Free flowing air to the Venturi is a great thing as long as it doesn’t upset the vents, air bleeds, or booster. Simple right? This stuff can really drive you crazy. Just keep reading and reading some more. Then go out and try what you learned. Eventually you’ll be as confused as I am!!
Oh and don’t bother removing the choke horn on the edelbrock/afb unless you are really bored. Out of all the things you can do to improve flow, that shows the least gain. Practically nothing.
Actually they suck!^^^ That's a good start for most.
Not even for a street car with a choke 
Ok so I read the first 7 pages of the extreme filters good and bad. Problem is no one at any point showed dyno sheets and I keep hearing things like different bases being used from countless companies give different results. So there are the non-believers and the guys who love them. That doesn't make sense because no one was middle ground and explaining why there is good and bad. I was looking for good empirical evidence and didn't get more then opinions. One guy posted some track numbers he ran and made his claims based on very little change in times/performance that couldn't be attributed to a million variables that are present when anyone runs down the track. This is going to drive me crazy! 
NEED MORE INPUT! 
NEED MORE INPUT! This has been experimented with as far back as at least the late 60's when Chevy was designing the L-88 Corvette air cleaner base probably even earlier carb inlet flow straighteners or air directors or whatever you want to call it.I think the conclusion has been there are no one size fits all solutions,you basically have to figure out what works on your engine in your car.I haven't priced the stub stacks lately but if they aren't too terribly expensive they might be worth a try,they've worked for some people,for others not so much but there's only one way to find out if they work for you.
Nope. The stub stack extends the bowl vents flush with the top of the stack. This puts the vent in a situation where laminar flow is going right over the top of it. That really pisses off the pressure in the bowl causing metering fluctuation and reducing atmospheric pressure in the bowl reducing the pressure differential between the bowl and the booster thus reducing the ability to pull fuel through the booster. Now if one epoxied tubes in extending the vent that would go a long way to fixing that problem as long as you didn’t get to close to the lid.Not even for a street car with a choke
Some of the people commenting are VERY sharp guys with decades of experience. If someone like Joe Sherman says he lost power every time, you can take that to the bank. And most people said they lost power. There are always going to be a few outlyers that may show something different but they are just that and the gains they have seen are minimal. You have to ask yourself if such a simple device showed a gain in most situations, why is it that most race cars that run a filter not use one?Ok so I read the first 7 pages of the extreme filters good and bad. Problem is no one at any point showed dyno sheets and I keep hearing things like different bases being used from countless companies give different results. So there are the non-believers and the guys who love them. That doesn't make sense because no one was middle ground and explaining why there is good and bad. I was looking for good empirical evidence and didn't get more then opinions. One guy posted some track numbers he ran and made his claims based on very little change in times/performance that couldn't be attributed to a million variables that are present when anyone runs down the track. This is going to drive me crazy!
I guess that's why the flow and dyno tests don't always translate to street or drag strip performance. I really can't visualize what is going on under the hood of my car once it is moving. You might get a clue as to what works or you could get misled. Only take-away from this: the clock doesn't lie!!!
After all this I would say the carbs may have been adjusted with the air cleaners off and it changes when you put them on.
I would just run what I thought looked best for my taste
I would just run what I thought looked best for my taste
Spot On assessment in my opinion. Back in the day of many camshaft changes and intake or carburetor changes we used to do I would not acquire a carb that had the air horns removed as I was afraid of what else was messed up in the plates or air passages. I even have the choke plates wedged open on my infamous two four 61 348, but I have the ability to start a two four car using just the throttle plates.
The other cars since are car show stock only and not tagged I sort of have to have the chokes hooked up and they actually work okRobert