Personally if it were me, I would figure out the hard start first then work
on the rest. Fix the basics before you can tune any futher.
Hard start cold with fireball..
Hmmm, flooding the carb, floats set to high, timing off, base and/or
advance, cams off a tooth. Improperly installed ignition system.
jon
-----Original Message-----
From: owner-land-speed@autox.team.net
[mailto:owner-land-speed@autox.team.net]On Behalf Of Dick J
Sent: Monday, March 27, 2006 6:30 PM
To: lsr list autox
Subject: Engine Problems
I'm curious to see what some of you guys come up with for possible problems
with my motor.
It's 461 cid BBC with World Merlin heads, J&E pop-up pistons (11.5:1) and
Comp roller cam. The valve lift is .668 and .678. Timing is at 35 degrees
total advance through an Accel HEI distributor.
The motor is way down on power and will only pull my Pontiac Trans Am to
150mph in the mile. I can feel the power come on better at about 4800rpm
when the cam comes on, but still nowhere what it should be. I'm shifting at
6000. There is a "popping" from the carburetor as it pulls. The warmer the
motor gets, the more frequent the popping. When the motor is stone cold, it
will not start until it throws at least one good fireball out of the
carburetor. Once the motor is warmed up, it starts really nice with no
fireball.
I've changed the fuel cell, fuel lines (1/2"), fuel filter(1/2" passages
throughout) , fuel pump(Holley Blue) and carburetor (1000 cfm Holley). I've
changed the plugs and wires.
One observer suggested cam timing or a possible bad lobe (bad lobe not too
common on a roller cam). One observer suggested the cam might be off one
full tooth, but it was pointed out that with the valve lift on this cam, the
pistons and valves would probably let me know if I was off a full tooth. I'm
thinking (and hoping) that the valves are set too tight and aren't closing
all the way. (I haven't yet checked the clearance.)
This motor should probably put out 600 - 700 hp or more. It feels about
like 350 - 375 when on the track.
Does anybody have any other ideas?
Dick J
In East Texas
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