Great information as usual. I understand about the differences in the shape of the dome and chamber, makes total since. Anyone have a table head height/ CR for the 2000. I realize that it's not exact but gives a starting point. I see reference to a NZ club that had one posted but the links no longer work.
Thanks again, Cheers, Terry
--Previous Message--
: Terry I measure everything to calculate
: CR. Two of the same heads could have
: different volume just due to a
: difference in valve seat depth.
: The problem isn't so much with the
: domed piston, it's putting it in the
: crappy bathtub chamber. You have to
: visualize the piston top up in the
: chamber and make sure there are no
: areas that are restricted. The domed
: pistons really belong in a hemi head.
: Also these heads don't have much squish
: area to begin with so anything that
: slows turbulence and flame front travel
: can be a problem. You can see it on the
: piston tops, there won't be any color
: on the dead spots.
: This isn't a huge dome, I doubt it will
: cause problems, you might just have to
: relieve the edges a little in the
: chamber in any area that would restrict
: the flow.
: Glen
:
: --Previous Message--
: Hi Glen,
: I have not measured chamber volume but
: the heads are 3.39 thick which
: according to the Tr6 guys should be
: about 9.75:1+ with 0 deck clearance. I
: haven't fitted the pistons yet but I'm
: assuming some clearance with the stock
: block. I'm assuming all things should
: be about equal with the domes in the
: 2000. I just measured my circle B
: @3.29, any idea what cr that would be
: with flat tops? I've seen some
: discussion that the domes slow
: combustion? Building Chevy's back in
: the day we always used "pop
: top" pistons, maybe the higher cr
: made up for the inefficient combustion?
: Thanks again, Terry
:
: --Previous Message--
: Well obviously the bigger the dome, the
: higher CR, but it can also cause poor
: flame front travel and "dead spots
: in the chamber. It can also negate some
: of the squish effect.
: Having said that, in this case you will
: probably be fine, it's not going to be
: flogged at WOT all the time.
: Have you calculated your CR with the
: domed pistons?
: Glen
:
: --Previous Message--
:
: Hi Glen,
: The domes are .30" x 2.0"
: dia. They are Hepolite 158112.
: Thanks, Terry
: --Previous Message--
: Terry how high is the dome?
: Glen
:
: --Previous Message--
: Hi Guys,
: I purchased a set of dome pistons from
: Rimmer cheap and I'm afraid that I'm
: trying to talk myself into using them.
: I'm building a 2000 Spit. for coast
: road fun. Triple Webers, Pheonix
: exhaust, aluminum flywheel etc. But I'm
: also building a 2500 Gt6 EFI as a
: driver. I have two Tr6 ported heads and
: a circle B as a spare. Would be nice to
: be able to mix and match? Just worries
: me that this is the same
: "logic" that BL used to
: create the domes in the first place. Am
: I creating a bottleneck to save a shave
: and a few bucks on flattops?
: Thanks in advance, Cheers, Terry
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