Hello,
I need to get another opinion about a friends Healey. Rebuilt 2639
cc .030" oversize engine, BJ-8 camshaft, Mallery distributor with
electronic ignition. The engine is not producing anywhere near the power
it should. It idles well, runs smooth, but is way down on power. It has
none of the low end torque or high end power that it should. Another
variable is the car has twin Weber DGV carbs on a modified BJ-8 manifold
done by Pierce injection. The setup is similar to the goose neck setup
for TR-6's. Measured the total ignition advance at 3000 rpm and got 35
degrees which seemed close enough. Checked the cam timing per Norman
Nock and his Tech Talk, set a wide running clearance, .095" in my case,
on valves 11 and 12. Set # 1 cylinder on TDC and measured the clearances
on 11 and 12. Should be the same clearance, in my case they are not. # 1
intake had .010" and the exhaust had .057" clearance. I backed up the
crank and turned it in the direction of rotation until #11 and #12
valves had the same clearance and they were the same at 6 degrees BTDC.
Total lift at the valves was measured at .360", very close to BJ-8
specs. Measured the opening of the intake and closing of the exhaust and
with .012" clearance at the rockers the intake opens at 26 degrees (10
degrees early) and the exhaust closes at 11 degrees (10 degrees early).
I would like to degree the cam but due to an after market crank damper I
cannot fit my degree wheel without pulling the radiator and lifting the
engine off of the mounts.
Norms test seems to indicate that the cam is advanced about 6
degrees, my test agrees with the cam being advanced about 10 degrees.
My guess is the cam being advanced while not good does not explain the
lack of power.
When I pulled the spark plugs they look very lean even at idle so I
suspect the problem is a very lean mixture across the whole rpm range.
Is anyone else out there running two Weber DGV carburetors?
I told my friend if it were my car I would remove the Webers and put on
a pair of HD-8's.
Regards
Wayne
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