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Thanks for the warm welcome fellas. I agree with the 4/7 swap. The only time I have seen good power from it was big cubic inch, large horsepower engines with ONE carb. Manifold distrubution means a lot there.http://www.svrehorsepower.com

Originally Posted by erik erikson

There is no way a Pro Topline 360 cc head will flow 440 -460cfm you would be lucky to break 420 cfm.The Brodix BB-4 Xtra with a port volume of 390 cc and fully CNC'D with 2.350/1.90 valves on a 4.60 hole will flow around 445 @ 28" of H20 at .800 lift.

You want to take a ride to charlotte and Ill show you a set. I have been getting a minimum of 440. To get 460 I have to angle mill them and use a 52 degree seat but they will go it. Keep in mind there is a lot of porting involved. They are about 390-400cc when finished.

well i have guys that are using the big 406 BMF heads that say are getting good numbers on the dyno i have run the 4-7 swap on small engines 548 but they were not dyno i would run one just for less deflection on the crank

Originally Posted by S V R E

You want to take a ride to charlotte and Ill show you a set. I have been getting a minimum of 440. To get 460 I have to angle mill them and use a 52 degree seat but they will go it. Keep in mind there is a lot of porting involved. They are about 390-400cc when finished.

It is not very often that I will admit I am wrong on things but I am on this one.
When I made the post about being lucky if the head flowed 420 cfm at .700 lift I looked at some of my info again I saw my info was for the 320 cc port volume head.
SVRE post about getting 440-460 is very possible with extreme head prep.
Looking back at my info I see that we did some 360 heads with a 2.30/1.88 valves that received a very good bowl, along with work around the valve guide, some work in the roof, race valve job and where rolled over about 1.5 degree's.Port volume was 365 cc's.
These heads flowed an averege of 424 CFM @ 28 H20.
Again I am sorry.My mistake.

No problem. Yeah, mine are far bigger than 365, but they are all for bigger inch drag engines with 15-16:1 comp. I also used a bigger 2.350 valve. 424 on 2.300 and 365cc is stout for sure.