Henry, I set the timing the same way as you! I presume that
this means that "you can never get too advanced". I doubt that
this is true, in the extreme, but usually your gas will start pinging
before you hit the limit.
I ask this because I used to use 100 octane low lead avaition gas.
My engine had a nasty run-on even on premium (leaded when it was available).
(probably a hot spot on the head somewhere). I cured it with the 100 octane.
I also found that I could turn the vernier on the dist. WAY advanced and NEVER
get pinging even with major lugging of the engine. I finally just advanced it
a little
over the "premium" setting and left it there.
-Tony
Message text written by INTERNET:triumphs-owner@autox.team.net
>From: Henry Frye <thefryes@iconn.net>
Subject: Re: timing tr3
Greg,
Every engine needs it's own timing setting, so picking an abritrary number
out of a manual is not the best way to go.
I never had any luck with a timing light on my TR3B. The fact I pulled a
major rookie error and installed the front pulley with the timing mark in
the wrong position might have something to do with it! :-) Also, you will
notice the lack of a scale on the timing chain cover. What I DO use the
timing light for is to verify my mechanical advance and my vacuum advance
is functioning properly. Disconnect the vacuum advance canister, hook up
the timing light and start the engine. Point the light at the pulley and
note the position of the pulley at idle. Then hit the throttle a few times.
The pulley will move if the mechanical advance is working. Then reconnect
the vacuum advance and check again. The pulley should be in a different
location at idle then it was at idle with the vacuum canister
dissconnected. If both these tests are good, proceed. If not, you need to
repair the offending advance.
I never had much luck with the "advance the timing for highest idle, then
back off a few clicks" method. I found the idle was pretty arbitrary.
Probably has something to do with my less then perfect SU carbs!
Here is what I do. Set up everything to spec from the book. Set the timing
using the static method. Or, just point the dizzy exactly perpendicular to
the engine with the vacuum canister pointing forward and adjust the vernier
to the big mark on the vacuum canister body. I think it is the 4th mark. Be
sure you are running the grade of gas you intend to run. That is important.
Set the timing using a specific grade of gas and always use that grade.
Drive the car at least 15 to 20 miles to make sure you are fully warmed up.
Then approach a moderate uphill at about 30 mph. Select third gear.
As you hit the upgrade, floor in, lugging the engine. If it is going to
ping, this is when it will do so. If you hear no ping, stop and advance the
timing a few clicks by turning the vernier dial on the dizzy in the
direction of the "A" stamped in the body. Repeat the driving test until the
engine starts pinging. If it pings badly, retard the spark a bit and
retest. You want to find the point that the engine just starts to ping.
At the point where the engine starts pinging, retard three to five clicks.
With this setting, you might hear a little pinging on a long, steep uphill
where you are really on the gas, but that's about it. If that pinging
bothers you, you can retard a few more clicks if you want, but I feel
retarding past the point described does effect the power a little.<
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