The OEM distributer on The "Daddy Bean Car", a Sept '77 Brown Roadster,
ailed about 2 months ago. The electronic distributer w/ integrated amplifier
failed about 2 month ago, so I replaced with a spare dist. from an early
'70s MGB w/ a HC engine. I closed the gap no the plugs down to the pre amp
dist., but did not bypass the ballast resistor that keeps the coil below 12
VDC. The car is original except that the air injector manifold has been
removed and the holes in the head plugged w/ what appears to be the
injection manifold runners w/ their ends flattened (they do not yet appear
to leak), and the solenoid that inhibits vacuum advance has been bypassed.
NOTE: before I advanced the timing I had been gradually retarding to
eliminate pinging in low gears below about 2500 RPM. Once i bypassed the
"transmission-controlled spark advance system" my pre-ignition stopped and
I have recently rebuilt the carb., but did not replace the mixture control
needle. I have had the car on a CO meter and it reads right @ 5% ( the
mechanic, who works on BMW & Volvo said that the hydrocarbon PPM was high,
and I'm not sure what that is symptomatic of except a ZS carb.).
So here is the question w/ the timing set to 15 BTDC@1500 RPM (vacuum
disconnected the car runs like ess ache eye tea: weak acceleration, lost of
carb. backfires when cold, runs hot, and cannot rev the engine above 3500
RPM in top gear.
So I advanced the timing a few degrees at a time until some where between 5
deg. and 10 deg. more advance. (counting 11 clicks on the micro-adjust/deg.)
We are much happier. Top speed and acceleration is improved, car runs
cooler, no more carb. backfires, but I am worried about running too much
advance.
PS how do you check total advance? w/ or with the vacuum advance connected?
and assuming that you check with out the vacuum disconnected does the
extra 10/20 deg. of advance that you get when you close the throttle at
high-speed harmful?
--
- Why are these athletic shoe salesmen following me??
Henry D. Reynolds hdr@jump.net
FONE: (512)448-3617 3205 Clawson Rd. Austin, TX. 78704
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