• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

TR2/3/3A TR3B Static Timing

Share this page

The pinking can be described as knocking, rattling, preigniting. The best description is how it sounds when you tap a steel hammer against the side of your cast iron block...and that IS pretty much what is going on in the combustion chamber when it is happening. It also sounds similar to the old "dieseling" you would hear in the early emmission years when you turned an engine off but it continued to run.

Lugging is when the engine is running too slow in too high of a gear, so your description is correct.

John
 
Don Elliott said:
During the run, while in 4th gear I step on the gas at about 1000 RPM.
Click to expand...

Just wanted to add that it's best to do the final test with the engine thoroughly warmed up or even starting to overheat a bit. The higher temperature makes it more apt to ping (or pink, or knock, it's all pretty much the same to the human ear even though there may be different processes going on inside the cylinder).
 
John and Randall,

Many thanks for the explanations and descriptions. I just wanted to be sure I understood clearly.

Happily, I don't experience any pinging-pinking-knocking and I always make sure my rpms are high enough to avoid lugging.

I understand that both (continued??) pinging and lugging can do some severe damage to the engine, and therefore to be avoided.
 
LexTR3 said:
I understand that both (continued??) pinging and lugging can do some severe damage to the engine, and therefore to be avoided.
Click to expand...

In general, that is true. But doing it briefly for this test will not harm anything. And the point is to test under conditions that make pre-ignition more likely than anything else you will normally do. If it won't knock while lugging a hot engine in 4th gear, then it won't knock any other time either.
 
Randall,

As I thought: brief lugging and pinging (for test purposes) is OK; extended or continued lugging and pinging is not OK.

BTW: Moss has a great video describing pinging that explains exactly what is going on in the cylinder and how to correct it.
 
Should we throw octane in to the formulae?

I always love how far the timing threads go!

John
 
The old timer's would be having a field day with us and how complicated we can make things..details details..
 
CJD said:
Should we throw octane in to the formulae?
Click to expand...

Nah, then we'd have to argue about what octane is (it's a chemical, right?) and why different ways of measuring it yield different results. And why no one uses the 95 octane fuel called for in the manual.

Then we'd veer off into altitude (barometric pressure), humidity, air intake temperature, combustion chamber deposits, cam timing, compression ratio, combustion chamber shape & material, etc (all of which affect octane requirement).

Not to mention whether just short of knocking is really the optimum ignition timing. If not, where is it?

It just keeps going on and on, like trying to unravel a Mandelbrot.

mandelbrot_450.jpg
 
John,

As a matter of fact, in the Moss technical video there is much about how increasing octane, or even adding an additive, is one way to deal with pinging/knocking.
 
Back
Top