Inake manifold runners are undersized from the head ports this is pretty common knowledge. Even aftermarket units are this way. Even worse are the cheaper chinesse manifolds which require alot of gasket matching to just match the head much worse than oem units. Hence why porting them makes power
Now like I said you want to see gains of atleast 20 cfm to see any really hp gains with a head. He will most likely not get that from that work. If he would of done bowl work/divider work even for a first timer he would of most likely got in that range and seen some real power gains.
Now will it make some power sure how much I dont know I have never done a head with so little work before.
People want to see 20+ whp on a ported head this is not going to do that.
My throttle body/manifold testing was done at guess what the track. It was proven over and over again a port matched manifold with atleast a 3mm larger throttle body+ the extra fuel required if needed would run .3-.4 tenths faster at the track.
We tested this on everything from sohc non vtec motors all the way up to h22a's.
Now if you doubt me thats fine stick to thinking that I sell snake oil. Ill keep getting people thanking me for the extra power
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