stangalator

hey everyone, doing a bit of research on ported pi heads, just giving the results.
i bought ported pi heads a few days ago and i was looking at the numbers for cfm and it looks as if the npi and pi heads dont flow that much apart, but porting your heads makes a huge difference, my question is, what kind of numbers does ported pi vs normal pi heads. i only ask this becuase going from npi to pi noramlly is a huge increase horsepower wise, without a "huge" increase in cfm. but going from pi to ported pi looks alot bigger...

i have a matlab graph of the data i recieved:



any thoughts?

avexhype

interesting, i actually heard from alot of ford people and mechanics around town that NON-pi ported heads flow alot more than ported pi heads. i cant vouch for that though

stangalator

bump.

Bullitt5339

There's actually been other testing done that has shown that most of the horsepower gains from npi to pi is from the cams and intake. I was also told a while back that once ported, the npi vs. pi flow numbers are too close to call.

stangalator

i heard the same thing a few days ago
how much more power is the ported pi worth over the normal pi heads?

Fobra

heavily ported PI heads flow between 215 and 230 cfm.... just around and below stock 4v heads. The word on the street is that the new trickflows hit 240 out the box, meaning that once ported and worked over they could possibly hit over 300 cfm, if they do that then I might buy them, but as it stands they have wicked turbulance in the upper band - something that doesn't seem right to me

stangalator

does this look like a "heavily" ported head?



just got them...

Stevecooper

Heavily yes, correctly no idea.

Fobra

yes they are ported, but as stated above there is no way to know unless they are flow tested

defconfire

I was thinking the exact same thing.

It looks gasket matched, but it also looks like it was hand done so you don't really know if it they did a decent job or had any experience with head porting.