best heads for the money?

mstngjoe said:

Port velocity is tied to the cross section of the port.

Do you know the cross section of the TFS head? It's 2.18.

How about the AFR 185 head? It's 2.23.

A difference of .05. Or less than 3%.

So how is it that the AFR 185 head is "too big" but the TW is ok?

Just curious.

Click to expand...

Because comparing the cross section of the 2 heads doesn't mean the velocity is the same. It's technical, probably more than i or most here can actually figure out without a program to do it.

Grn92LX said:

Not very true

http://www.corral.net/forums/showthread.php?t=599345

I do agree with the twisted wedge recommendations though. Back years ago when I bought mine they were even more of a bang for the buck @ $935 to my door

Click to expand...

Good reading, thanks for the link......
Not sure if I'm sold on it but I did gain a few more pointers.

mstngjoe said:

Port velocity is tied to the cross section of the port.

Do you know the cross section of the TFS head? It's 2.18.

How about the AFR 185 head? It's 2.23.

A difference of .05. Or less than 3%.

So how is it that the AFR 185 head is "too big" but the TW is ok?

Just curious.

Click to expand...

Well cross section is cross section...how bout you calculate the flow area throughout the whole port and then show me the percent difference. Port volume is obviously an important factor or else they wouldnt classify heads by port volume. Just curious.

If you average the flow (as reported on the respective websites) from .200 to .500lift of the AFR 185 and TW, there is less than 3 cfm difference.

Here's something else to consider.

Flow at .500:

AFR 185 267 cfm. 267 / 2.23 = 119.7 cfm psi

TW 251 cfm. 251 / 2.18 = 115.1 cfm psi

And it is correctly stated that accurately measuring velocity is beyond most of us. To give an idea of just how complicated it is check out this thread:

http://speedtalk.com/forum/viewtopic.php?t=4889

As to the OP and his question.....If it were me, I'd wait and do the whole package at once and correctly match the parts for the desired application/performance level.