dibbons
Well-Known Member
I will be using factory open chamber heads on some street build 340's that will see occasional drag strip time trials.
I would imagine it cuts back on carbon buildup too.
I can't take credit.... That goes to Ryan at Shady Dell. And he did an amazing job on the portwork! Very consistant from port to port.
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It is time consuming to do a nice job---con.
It does retard how quickly carbon will build up in there, but it will build up eventually anyhow, smooth in form comparatively tho'---pro that diminishes with time.
Heat rejection is improved, but the amount is debatable & the effect degrades with the inevitable progression of the above---pro that diminishes with time.
The next time You've got 'er torn down, they'll clean up a lot easier---pro
You won't be removing more than 1-2cc's at most just doing that unless You start relieving the chambers on purpose, and there's really none on a smallblock to do,
so I wouldn't anticipate a problem with the squeeze. I have seen BB 906's (more than a couple) that have the chambers that represent cyl's 3&6 cast ~.025" shallow
compared to the rest,..that is an issue, and I've corrected them.
I can't take credit.... That goes to Ryan at Shady Dell. And he did an amazing job on the portwork! Very consistant from port to port.
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Polish them don't grind them.
What size stems are they? I might have an extra factory 3/8" stem size you can haveI have some old 1.88's but they won't fit. I need to find at least one old 2.02. The old 1.60's I do have.
Ok. I'll look tomorrow and let you know tomorrow eveningFactory 3/8" stem is correct.
Intake ports only,?You can see some pretty nice gains with a rough texture similar to golf ball dimples in the porting job... lots of discussions about this on many sites.
Intake, bowls and chambers. Done with a slightly bent carbide burr with a few teeth broken off to help the texture... golf ball dimples work, too.Intake ports only,?