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Re: Smooth breathing?

To: Victor Laury <vlaury@earthlink.net>
Subject: Re: Smooth breathing?
From: Ronnie Day <rday@cyberramp.net>
Date: Wed, 3 Mar 1999 11:02:55 -0600
Gary said:

>Matching the bores when there is such a small step size, and especially
>if they are smaller, rather than larger, than the phenolic blocks, is,
>as some other posts mention, probably not worth the effort.

I'm not so sure. Even a small and/or partial lip anywhere in the airflow 
path MIGHT tend to create interference swirls far out of proportion with 
what you'd think. You're pushing the air column against and past a (so to 
speak) flat wall. Has anyone seen any photos of airflow under these 
conditions? Of course you could just measure the difference, if any, in 
airflow between unmatched and matched ports, but that would be as much 
fun to look at.<G>

It would also be interesting to find out at what point a difference in 
manifold and port size does become a major factor. For instance, the SU 
(SSS) intake for an L-16 has 1 1/2 inch ports whereas the OEM L-16 heads 
had 1 1/4 ports. It would be interesting to compare flow with that 
combination, with the head opened up to match (Street Prepared legal) and 
with the SSS 1 1/2 inch port head. That info may be floating around 
somewhere or you might be able to model it in one of the desktop engine 
programs.

FWIW, Ron

Ronnie Day
rday@cyberramp.net
___________
The ACL Group
Arlington, Texas
(817) 572-0873 (V)
(817) 478-2896 (F)



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