air cleaners best worst?

[jet1]

This is what I have right now with a 3" x 14 element.

Picture 143.jpg

[MadBill]

The lid should be fine. The base I'd say not the best; not the worst. Better than the spun designs I mentioned, but not as good as the smoother contour of the true L-88 (and others, such as Z-28) design. As mentioned, a 4" element is cheap insurance against restriction.

[SchmidtMotorWorks]

I don't think you will find much flow difference in any reasonable air cleaner but you will find difference in the performance that comes with cooler air if the air cleaner does not transfer heat to the air as fast (as aluminum does) and if the under-hood temp is high, ducting in cold air will make far more difference than air flow.

[gr9082]

Braswell filter is 4 to 8 HP over all filter I tested

[rfoll]

X2 on the cold air. GM saw fit to install it on cars from the '70s on. One of the local speed shops tested these against everything they had on hand, and they came out on top. They are only 14" and a Holley carb will need a small spacer. Nice smooth curve on the inside. If I rember, it's something like 1 percent more power for every 10 degrees you reduce the temp of the air feeding the carb.

[MadBill]

In a post some years back, bigjoe said the dyno air turbine usually made more power than no or any air clearner! Myabe not the most practical choice though..

[Bob Hollinshead]

Braswell filter is 4 to 8 HP over all filter I tested

I can't find a picture on Braswell's site, does anyone have photos of this filter assemby?

[MadBill]

Got one somewhere, I'll try to dig it up. The OD is tapered..

[justahoby]

would them air cleaner lids that are also an air cleaner themselves help? or is it just a gimic? seems like it would bypass this problem, jst curious if was tested. Does it get affected too by how close it is to the hood..

[MadBill]

I think the only place the K&N Extreme filter lid would help would be if there wasn't room for an adequate height normal filter.

There are numerous reports of substantial power loss when using them with taller units. Some say it's because "carbs are designed for air to flow in from the sides." and they don't work when fed from above, but of course that's exactly how an air turbine feeds the engine on the dyno. I suspect it's the turbulence that ensues when the lateral flow from the normal filter encounters the vertical flow from the lid...

PS: Here's a shot of a Roush carbon fiber box for a 16" filter, modified to fit a spread bore Braswell. note the smooth contours..

[justahoby]

it seems like a crazy idea carbs a designed to breathe from the side to me also lol, but i would agree a taller filter may be better. Those xtreem lids are pleated, they are above your carb at different angles creating odd turbulence when the carb would like to pull down... so would a large filter, regular shaped,easy breathing, that lets in air through much surface area around, create a well fed low turbulence area , of air available for the the carb to draw in... kinda like a large plenum of air above the carburetor.. maybe i am over thinking this... ... but if so i got a lot of room under my 69 c10 to just go with a tall filter.. Real tall..

[RCJ]

I have always wondered if you had a radius on the lower half then on the lid if the radius started the same but decreased.Basically a venturi above the carb would this create more power.

[af2]

Bill, I feel the one I use is pretty good. 16"

[MadBill]

I'd think that unit would cause some restriction.... at about the 2500 HP level!

[Vintrcr]

Just for reference here is a factory 1969 Z/28 base. (open element-non cowl)