Hi John
Many thanks for your reply. You are the only reply with real info to date,
which I find amazing given the interest in 6 cyl performance mods.
Anyhow, the article by Witor in April 99 , Six Appeal presented 2 graphs,
both identical. A bit confusing!!!
It is not possible to properly evaluate the data on flow because Chris has
not provided the pressure drop used.
The "industry accepted" value is 10" water gauge, and if he used this, then
the general equation for estimating HP can be used. It is.............
Peak Engine HP= 0.43 x peak port flow in CFM (at 10" WG) x no.
cylinders
Using his figures, a standard head would flow 103HP (about right) and a
modified head with 31.25mm valves would flow 150hp, again, not a bad guess
based on my experiences.
I would like to get a copy of Witors article in Six Appeal Edition 109. Can
I buy a copy from the club please??. If so, I'd appreciate if you (or
somebody else) could scan and e-mail thru the article, whilst I wait for the
original to come via post
regards,
Cindy & Terry @ ESP
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