Valve Stuff: What's it cost?

Someone gets in touch with me over on the Secret Channel. So I take
it down, spin my Captain Midnight Secret Code Ring and the message is:

"So whats all this valve stuff COST, eh?

Cheep. As in, Durt Cheap. New guides, figure a couplea bucks each,
although with so many schlock shops going outta business you can often
get them for a buck each if you take the whole bin.

Each valve gotta have a guide, so you need eight per engine. You
drill then adjust the temperature of the heads (never do just one if
you can help it) and then you REAM to match your particular BATCH of
valve guides. NEVER assume the numbers on the box are valid. For
ANYTHING.

Then you gotta have SEATS. Which come in different SIZES. Intakes
are bigger than exhausts. BIG seats, mebbe 44mm (1.73") run you mebbe
$10 each. (Truth is, I donno... been a while since I bought any;
still got some left, except they're all stock sizes. 44mm is one of
those Brazilian Alcohol sizes; they tell the Kiddies they're Racing
Heads!! Sell like ice cream at a Fourth of July picnic. Down in
Brazil it's just your basic alky head.

Exhaust Seats are smaller than Intake Seats; price covers about the
same range.

You need one Seat per valve and you wanna figure eight to ten bucks
per seat, so call it $80 per engine. But don't go crazy with regard
to SIZE. 44mm is TOO BIG for an aircraft engine; you want your
intakes to be about 1-3/8" to 1-1/2" and you want your exhaust valves
to be about 70% the diameter of your intakes. Also, if you're
building just a basic engine on VW components, Single Port heads will
do you fine. Just make sure the valves are LARGE ENOUGH. (Lotsa guys
use single-port heads then go to dual-ports an' say 'Gee, the dualies
are SO much better...' and you take a look at them and they've gone
from a 32mm intake to a 36mm intake and you can stand there waving it
in their faces all day long and they simply DON'T GET IT... so why
bother.)

Your engine's gotta breathe. Single or dual is less important than
the SIZE OF THE VALVE. ( ...an' after that, we get to worry about
the AMOUNT OF LIFT, because here again, it's kinda like the Dual vs
Single bull****, with guys going for valve lifts suitable for
launching a Redstone missile, when what they REALLY need is something
around a quarter the diameter of the valve. Anything more, it's
wasted effort. (Remember, it takes a LOT of energy to open your
valves and pump your oil and do all them other 'housekeeping' chores.

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Okay, so you got valve stems and valve seats and valves and springs
and retainers and keepers... and believe it or not, you ain't even
HALF way there! Why? Because we gotta make sure our heads are
BALANCED. Not by mass but by VOLUME. And for that you gotta cc your
combustion chambers, which means you need a cc plate and some kind of
a CALIBRATED filler, such as a BIG syringe, or a laboratory burette.
And once you've got all that stuff you gotta figure out the degree of
PRECISION you're going to observe.

There's 25.4 linear millimeters to a linear inch. And since we're
dealing with VOLUME, there's 16.381 cubic centimeters to a Cubic
Inch. At 25.4 millimeters to the inch, you can see it's a tad larger
than 1/32

There. That's a cubic centimeter. If you want to make a GOOD engine
you'll make sure all of your chambers are within ONE CC of each
other. (Can you even DO that? I mean, that's TINY!)

Then try this on for size. A REALLY well-built engine -- the kind you
see at the finish line, with the driver getting his champagne shampoo
-- THAT engine has chambers balanced to one TENTH of a cc!
(Seriously).

Is it worth it? That depends on you. I shoot for a tenth but I'm
satisfied with a couple of tenths. And it isn't as hard as it looks.
Like most everything else in building a good engine, it depends on
your TOOLS. I've posted some pictures of your basic burette,
something that's good for 1.0cc. I'll post another showing how you
get down to 0.01cc.

But right now I gotta go take some pills...

-Bob