On my newly rolling (hit second gear in my driveway!) 74 TR6 I am still
having issues with the needle valve hanging up and the car wanting to run on
full choke and sputtering out without it.. hope the wisdom here may have
some ideas..
Some facts;
Needle Valves
New needle valves in both (stock) carbs, work fine for a bit then seem to
jam (DOWN of course) causing gas to pour out the breather. I pull the bowl,
clean the valve and work it, put it back and its ok for a while. Gas tank
was flushed and doesnt appear rusty, new fuel filter before pump (clear)
has no particulate matter in it. I am putting (if I can find one) an in-line
filter just before the carbs and see if that helps. I remember someone
talking about a replacement for the needle valve setup that is less prone to
sticking but dont see it anywhere, any help on that would be great..
Choke / Richness
Not sure if this is due to a slightly aggressive cam needing more fuel or
what. With the timing set at stock parameters the car (using full choke)
starts instantly and runs very smoothly at a high idle. If I crack the
throttle I get instant response without hesitation and its quite smooth and
crisp. After the car warms a bit I attempt to remove some choke (go to =)
and the car will sputter and attempts to crack the throttle are met with
spitting out the carb. Im going to go the whole route of adjusting the
carbs but wonder if its the new cam that is causing this, maybe needing
more fuel via larger jetting? I know NOTHING of the new cam specs meanings
but here is what I have if one of you experts can make sense of it..
ADVERTISED DURATION IN254 EX-254
.50 Duration IN-222 EX-222
CAM LIFT IN-280 EX-280
VALVE LIFT IN-.420 EX-.420
VALVE LASH HOT/COLD IN-108 EX-116
CENTERLINE LOBE SEPERATION - 112
CHECK TIMING AT .050 TAPPET LIFT
IN OPEN - 3 BTDC IN CLOSE 39 ATDC
EX OPEN 47 BBDC EX CLOSE -5 ATDC
SPRING PRESSURE 110 LB SEAT 250 LB OPEN
Thats it, if anyone has any advice feel free to let me know!
Thanks
Gary Radocchio
74 TR6
Woodbury, CT
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