Total Length:
Dead Stack:
Total Move:
Piston TDC:
Spring, 160#:
Spring, .507:
Spring, .507:
REx
1.980"
0.787"
0.630"
0.337"
1.431"
0.924"
345#
RInt
1.987"
0.787"
0.582"
0.277"
1.382"
0.875"
340#
FInt
1.981"
0.784"
0.590"
0.330"
1.350"
0.843"
345#
FEx
1.968"
0.776"
0.607"
0.246"
1.398"
0.891"
350#
REx
0.668"
RInt
0.635"
FInt
0.660"
FEx
0.646"
Measured the four valve springs first, then went through all four
valves on the heads w/test springs, working from the rear exhaust
valve (REx) to the front exhaust valve (FEx):
UPDATE....
Spent some time with the valve checking tool, test springs on all four
valves, then the valve springs on all four, then on the heads to test
for piston clearance....
UPDATE:
Working on valve spring preload and clearances.
When I set up the dial indicators on the front head and dialed in the
TDC specs, I found I had the exact same clearance, 0.023", so I
repeated the same process with these valves, took off 0.014" off the
diameter of the intake valve, and 0.020" off the diameter of the
exhaust valve, and rounded off the sharp edge fading the piston,
and ended up with 0.054" clearance !
Now to check the spring settings at full lift, make sure there is no
coil bind and some minimum valve space left to compress, and then
to "clay" the pistons and see what the piston to valve clearances
are....
59 Harley 93 ci Project
Page 3
Got the heads back from my machinist, he had cut the seats and
sunk the valves an additional 0.040" into the heads. Set up the dial
gages on the rear head, and dialed in the TDC cam settings of 0.198"
for the intake valve, and 0.186" for the exhaust valve from the cam
chart.
Started with the front cylinder exhaust valve:
Valve Diam. after valve clearance work: 1.728"
Valve Stem Protrusion: 1.580"
Valve Spring Length (unloaded): 1.972"
Valve Spring Length (solid): 0.775"
Valve Spring Length (+0.060"): 0.835"
Max Valve Lift: 0.507"
Desired Installed Height (0.775+0.060+0.507): 1.342"
Spring Load at Desired Installed Height (1.342"): 180#
Spring Load at Max Lift Height (0.835"): 380#
Actual Installed Height, no shims: 1.540"
So now I need to decide if I want to pack the valve springs down to
an installed height of 1.342", which will require 0.2" of shimming, a
whole lot in my opinion, will need to think this over a bit....
more later
The upper valve spring retainer on all four valves hits the top of the
valve guide before spring bind occurs.
Just a shot of the heads on the motor during the TDC check with
the test springs:
Some explanation here:
Total Length and Dead Stack length, measured on the bench and in
the vise.
Total Movement, valves with test springs measured in the heads.
Piston TDC, heads on motor w/ test springs, valve movement to
piston contact at TDC shown.
Spring, 160#, valve springs in vise, length at 160#.
Spring, .507, first measurement is in vise, length at max cam lift,
second measurement is the pounds the springs are generating at that
lift.
Tried to get an installed length on the valve springs, but the bottom
of the springs are in a recess in the heads and I can't get an
accurate reading of the installed length. Best I can come up with is
that it is around 1.40"
Put the valve springs on and measured the max valve movement
available with no valve shims:
Got a clearance of 0.023" between the valves. They were hitting
before, and at a lift of only 0.160", so this is a big improvement....
The specs call for a minimum of 0.040" clearance between the valves
at this point, and I prefer 0.050", so the valves were chucked up in a
drill, and spun against a 80 grit flapper wheel on a bench grinder...
I was guessing I needed to take off about 0.014" off the diameter of
the intake valve, and 0.020" off the exhaust valve, and I also wanted
to smooth and round off the sharp outside edge of the valve a bit
on the side facing the piston. This should give me 0.007" + 0.010"
additional space between the valves, not calculating for the difference
in valve angle, which will make it less....
Stuck 'em back in and dialed in the TDC lift settings, and bingo, I
had 0.052" of clearance !!
Got lucky, wanted to sneak up on it a little, figured I'd get at least
0.040" on the first go-round, but I think by rounding off that sharp
edge on the valves facing the piston, I got more clearance....
