Not to hijack, Chris are you related to Jared and Julie?

Yes that is true, airflow is only part of the solution and might not even be the most important factor. When people are "benchracing" they usually assume that more airflow is better but of course that isn't true. The old saying is that "a sewer pipe flows a lot of air but it won't make any power".

Harry is my dad...

That chart allmost looks like an intake port...

I'd agree with pretty much everything noted here. Manufacturer's published numbers are usually manipulated a little. Flowbenches in general are tools as good and repeatable as the weather and their operators. I use 2hp/cfm for a race effort, but as Andy said a street engine is a compromise in most areas so you will more than likely see closer to 1.5-1.75hp/cfm on them. The cam needs to make use of the higher flowing lift points of a head package. Let's say a cam has a valve lift of .600 and duration at .050 of 250°. If the heads flow ok(say 245cfm) at .400 lift and hold it steady to .600 you will make more power than a port that moves less air but still climbing (say 235) at .400 but ends with 265cfm at .600. The cam's area under the curve (the actual lift curve as measured at the valve seat) is what has to match the port flow rate and volume. If it's flowing better earlier (at lower lift), it will flow more thru the whole valve event than a high peak number and average mid lift. That's because the valve spends most of it's time between 2/3 lift and full lift than it does at full lift. So cam for mid lift rather than peak.

X2
More flow is only better if the engine is too large for the existing flow rate. Increasing CFM to 300 on a 350" motor will kill everything below 4,000.
More low-lift flow may also throw your cam choice out the window - if it was spot-on for LSA and overlap before, increasing .100-.200" flow effectively stretches the overlap triangle and will raise and narrow the power range - but may not add anything useful.
The reason why it works for most V8 engines isn't the theory (flawed, as Andy says), but the fact that 2-valve engines in general don't have enough area.

Thanks guys for your valuable comments
and also for your ideas how to get out the best HP/$ combo for a street engine like this

AndyF, I read somewhere that you just finished up an article for Popular Hot Rodding where you used a Comp XR292HR-10 hyd roller cam in a 505 inch BB Mopar. Do you know when that article will be published?

I am interested in the article because I will use that same Comp cam in my stroker.

What you experts say about my combination of 440Source heads + Comp XR292HR-10 hyd roller cam with 242 int./248 exh.duration @.050" Lift + Mopar M1 intake?

I have on the shelf also a old Holley SD and a Eddy RPM from previous projects. Which one would you prefer?

I have on the shelf also a old Holley SD and a Eddy RPM from previous projects. Which one would you prefer?

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For a street car the RPM... you wont be spending much
time in the upper RPMs so go with the added torque

well ive seen the rpms flowed ,,so
you can always disput numbers
2 sets 285 -- 292 out of box on 2 diff benches
rpms do not bode well in porting
best seen was 315 best
rpms tend to bring something to the table that
a meter or flow bench wont say
the pickup over a stock 452 is around 2,5 -3 tenths
i know that out of box rpms will diff run
deep into the 9 s without any work
flow number dont mean much to mee other than they will do what the builder says
might not work at all on the track
to me thats all that matters

July 2010 PHR has the 505 article in it and is on the newstand now.