Anderson N/A power pipe vs C&L true flow

Well when you buy a piece of 4 inch PVC, that is the inside, or working diameter. The outside diameter is actually something like 4 5/8 inches. I just designed a bunch of PVC duct for a substation in New York so I am down with PVC!

Ideally, you'd want a perfectly straight tube that has no bends. A bend is a constant in terms of head flow reduction. You can go to the back of any fluids book and look up the table for a 90 degree elbow.

A change in pipe diameter size is different, in that the formula involves the radius squared, so its not a linear relationship. So the ideal intake would be something like a 75mm meter with a 75mm TB all using 75mm tubing. When you change the pipe size, you impact the pressure and velocity of the flow. Pressure and velocity are inversely related. The energy of the air charged is disturbed when one or the other is changed, which causes flow to be lost.

This is why I have a problem with the argument of sizing TB based on what the engine can flow. If engine X can only consume Y CFM flow, then some say get the TB that can feed that max flow. My opinion is to get a TB that can over flow that amount, because by the time the incoming air goes through the entire intake tract it will have lost some Z amount of head.

Sorry about the length.

Adam

Black95GTS said:

This is why I have a problem with the argument of sizing TB based on what the engine can flow. If engine X can only consume Y CFM flow, then some say get the TB that can feed that max flow. My opinion is to get a TB that can over flow that amount, because by the time the incoming air goes through the entire intake tract it will have lost some Z amount of head.

Sorry about the length.

Adam

Click to expand...

But that is the thing, a 65mm Accufab can outflow any street 347 out there...

You have to think, the 347 cfm flow numbers (600+cfm) are with NO heads/cam/intake. Of course the cam is big on only letting in (for example), 220-240* of the crank rotation from the cam. So you only get a fraction of the non-restricted number of 600+ cfm...which is 100% V.E.

I thought this was interesting...

http://www.corral.net/forums/showthread.php?t=925346

On a 351 with AFR 225 Heads and other 'big' parts for 'big power'... Look what that little 77mm object with an obstruction can do...

Another note to add Adam: The Holley Systemax has a 75mm opening at the throttle body mounting point. But hey, guess what it 'necks' down to a couple of inches in. Yep, a 65mm opening

5spd GT said:

But that is the thing, a 65mm Accufab can outflow any street 347 out there...

You have to think, the 347 cfm flow numbers (600+cfm) are with NO heads/cam/intake. Of course the cam is big on only letting in (for example), 220-240* of the crank rotation from the cam. So you only get a fraction of the non-restricted number of 600+ cfm...which is 100% V.E.

I thought this was interesting...

http://www.corral.net/forums/showthread.php?t=925346

On a 351 with AFR 225 Heads and other 'big' parts for 'big power'... Look what that little 77mm object with an obstruction can do...

Another note to add Adam: The Holley Systemax has a 75mm opening at the throttle body mounting point. But hey, guess what it 'necks' down to a couple of inches in. Yep, a 65mm opening

Click to expand...

I would agree with your logic if the throttle body was attached directly to to the intake and the blade side of the throttle body opened straight to the atmosphere.

As to why the Holley Systemax necks down inside the intake, well I would guess that the engineers at Holley have forgotten more about air flow then I have ever learned, and if they build an intake with a 75mm opening that necks down to a 65mm opening inside the intake, then they did it for a reason.

And unless everyone performs the fox conversion, using Accufab throttle bodies as an example doesn't make sense in this forum.

Adam

I still don't see the advantage in a 3.5" or 4" id piece of pipe when you just
ram that airflow against a lip because of the 75mm or smaller size tb
opening

Grady

Black95GTS said:

I would agree with your logic if the throttle body was attached directly to to the intake and the blade side of the throttle body opened straight to the atmosphere.

As to why the Holley Systemax necks down inside the intake, well I would guess that the engineers at Holley have forgotten more about air flow then I have ever learned, and if they build an intake with a 75mm opening that necks down to a 65mm opening inside the intake, then they did it for a reason.

And unless everyone performs the fox conversion, using Accufab throttle bodies as an example doesn't make sense in this forum.

Adam

Click to expand...

The Holleys and BBK's all flow VERY similar...but the Accufab was an example.

Of course they did it for a reason...velocity What I'm saying is the 75mm going into the 65mm ACTUAL opening means the 75mm TB is doing NO GOOD.

On foxes, for example, the throttle body can be connected directly to the intake...(delete the egr). So I took your comment about not believing the throttle body cfm range as for all stangs. So I simply am correcting that...

I run the Na AFM power pipe its nice having everything tucked away in the fenderwell. Its a lil stretch for the MAF wiring but can be done easily not a lot of room in there though. Mine made very lil noticeable but after experiencing how bad the C&L stuf worked on my car I went Pro-m and never looked back. Pro-m 80mm and AFM power pipe its worked great and never had any problems. The C&L was nasty it was like somedays the MAF wanted to work and others it didnt. Anyway thats another story all together.
AFM NA POWER PIPE ALL THE WAY!!!