Huh… now you guys have me wondering about a filter question of mine… is there any evidence that the filters with the inside cone of additional filter pleats in the nose (you know, the ones that all the import stuff seems to use) flow better or worse then just your normal filter?

Anyplace out there that lists actual CFM numbers for filters?

 

I have one of those filters on my car, with the inverted cone on the end. If you Google S&B Filters, you will see which one I have. It has a 4" inlet, and its 9 inches long. I remover that panel entirely under the filter, and have the corner of the airdam aimed at the filter. This is at the end of a K&N FIPK, stock MAF housing descrened, Vortech elbow with the divider cut out, AS&M 58MM TB. If someone can host the pics for me that would be great.



Nick

 

I recently ditched the MAF and started a Speed Density tune. At the track this weekend I logged a run and noticed that MAP is still wierd. One record it'll be at 99KPa and the next record it'll show 94KPa. Not stable at all. I've still got some splainin to do Lucy

Oh yea, I didn't pick up a flippen thing on 3 time shots.

On air filters - Where the heck does K&N list air flow numbers for their filters?

Steve

 

They don't--- call them and they have all that info.

 

My filter (6" dia X 9" long) should flow about 1150 CFM. Anybody know what a stock LT1 intake with a 58mm TB flows at 1.5 " Hg. Also, my manifold pressure is not the worst at peak torque (as suggested). Mine keeps getting worse as rpm goes up past peak torque. I gotta believe there's a few ponies in here somewhere.

 

According to user "anaik"
The Stock MAF on a Superflow 300 flows 759 cfm with screen and 979 without.

According to me:
I put a zo6 MAF on the bench and it did 1202 cfm at 28". Test were done at 5" and converted.

 

MAF, Filters and TB/Carbs are rated at 25" of H2O or 1.5" of Hg.

Bret

 

I just wanted to compare the results to what i had for my throttle body which Accufab published. No idea whats the right/wrong way.

ACCUFAB 90MM RACE
TESTED @ 3" - 449 CFM
CORR @ 20" - 1158 CFM
CORR @ 25" - 1297 CFM
CORR @ 28" - 1369 CFM

 

I wouldn't worry too much about cfm @ such & such depression. Calculate airflow demands for the engine, be realistic about VE, then calculate velocity through the effective throttle area. Shouldn't exceed 250 feet/sec if you want to keep losses to a minimum.

-Mindgame

 

OK - just some rough numbers

355 CID @ 6800 RPM @ 100% VE = about 700CFM

2 58MM holes = .0567 sqft of flow area

Turns into 205ft/sec velocity

of course: VE ain't gonna be 100 at 6800 RPM - and the 58 MM holes are some what plugged up by throttle shaft and blades. But in general it looks like a 58 mm TB falls in line on 355

 

The K&N formula is basically 6 cfm per square inch of face area (ignore the pleats)

This will be the number they give you on the phone. They don't flow test their whole lineup. You just go to the website and get the specs and do the math. Subtract .75" of height to deal with the rubber flashing on the filter.

 

Thanks for the K&N info. According to that, my filter is good for 1398CFM

 

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