In a message dated 5/23/02 8:09:52 PM Mountain Daylight Time,
bobmgtd@insightbb.com writes:
> Now the question: How do I time the engine now? I realize I have to use a
> timing light now (been doing it this way for years on the MGB). But how
> many
> degrees at what rpm?
What you need is the correct timing for the engine the way it is today (not
when it was new 50+ years ago), using the gas available today, under your
driving conditions. The numbers from any book are only a ballpark place to
start. I drive my cars at high altitude here in Colorado and I always find I
need more advance than "the book" calls for. Here's what I do:
(1) Make sure the distributor is in good condition and that the mechancal
advance is working properly. This is essential or you are just kidding
yourself.
(2) If there is a vacuum advance, disconnect the vacuum and plug the line
with tape.
(3) Position the distributor timing so that the car will start. This may
take a bit of trial and error after replacing the point system with
electronic. It is often not the same location.
(4) With the distributor somewhat loose and the engine running, slowly
advance the timing. RPMs will increase and the engine will run more smoothly
as you get into the proper region. Then the engine will start to faulter as
you go too far. Back the timing off again until you are once again in the
"sweet zone".
(5) Tighten the distributor and read the timing advance with a timing light.
The best type to use is one like the unit Sears sells that has an advance
dial on the light. You simply line up the pointer on the car with the timing
mark on the pulley and read the timing on the dial.
(6) Take the car for a drive. Get the engine fully warmed up using the
gasoline you intend to use (octane and brand). Drive up some hills and
accelerate quickly (quickly for a T-series!) from stop and from several
different speeds. Listen for pinging. If you consistently get pinging going
uphill or under acceleration, or both, you have too much advance.
(7) If you had pinging, loosen the distributor and retard the timing about 2
degrees (this is where the dial type timing light is worth it's weight in
gold!). This will be a very small change in the position of the distributor.
Go drive the same route again and note any improvement in the pinging. If
pinging is still excessive, retard the timing another 2 degrees.
The above procedure will get the timing correct for your car under your
conditions. It's a bit more work than just making a setting out of a book but
it's worth it. Basically, you are after as much advance as you can get in
order to maximize power without pinging.
Ray G
Colorado
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