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MGB MGB tuning conundrum

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Haven't heard from Hap for a few days

Edit, see he posted in the racing forum yesterday
 
Hap's racing this weekend (lucky guy!).
 
drooartz said:
Hap's racing this weekend (lucky guy!).
Click to expand...

I heard he was installing an engine while there.
Some nasty mean MGB motor. 14-1 compression or
some crazy stuff like that. Just a rumor.
:wink:
:jester:
 
Drew--- the jets should START with the top being even (level) with the venturi platform. Then 12 to 13 flats down.

With a vernier style caliper you can set the depth by pre-setting the instrument and lowering the jet to match it... but I can't recall how far down it should measure.
Something around a quarter of an inch methinks, but just not sure. :frown:
 
I think I'm getting closer. Car is running better on the move with no more hesitation at wider throttle openings. Idle is lumpy even when warmed up.

Here's tonight's settings:

* Champion RN9YC gapped at .032"
* Jets at .060"
* Timing to 30* @ 3500 RPM

mgbplug-3.jpg
 
Legal Bill said:
Back in the day, we static timed all of them (after we made sure everything else was right) and then we drove it. If it did not run right, we would change the timing by a dagree at a time and repeat the process. The A and B series motors both should rev to red line without a problem. We would adjust until we found the maximium return based on seat of the pants, and sometimes a series of timed 0 to 60 runs. Engine pinging and run-on after switching off the ignition were the two fence posts we tried to tune between, followed by ease of restarting.
Click to expand...

I have only had a timing light for about the last 5 years or so. Long ago I read somewhere, think it was a Triumph manual, to advance the timing to get maximum speed at idle, back off a few degrees, test drive up a slight grade and see if you get any pinking or detonation, basically fine tuning as legal bill suggests. Which is kind of fun, and pretty intuitive and easy to do.
 
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