Dick, It does not matter one hoot what we think it is. The only thing
that matters is what is the problem. Start with looking at the spark
plugs. Does the advance in the dist. work right? Take the valve covers
off and look for a problem. Take a compression check, make sure top dead
center is marked right. Cam timing is easy to check with the valve cover
off and a true TDC mark. Don't jump to conclusions and start at the
basics and work forward from there. Doug Odom in big ditch
Dick J wrote:
>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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