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MG TD TF 1500 - Balancing the distributor?

I was reading an ad for a blueprinted BMW 2002Tii on BAT, and it said that among the many upgrades was a balanced distributor. That's a new one on me - any help to understand the process would be appreciated.

Tom Lange
MGT Repair
t lange

Probably to counter the effects of non working turn signals :-)
L E D LaVerne

Y'know... sometimes I wonder myself.

I get balancing something like the crank, flywheel, etc., but when I hear someone tell me they balanced the water pump impeller or the generator pulley to within a gnat's balls, I know someone has a whole lot more time on their hands than I do.

Maybe they meant to make the weights equal...?
MAndrus

Never balanced a distributor, but water pump pulleys should be balanced within reason to ensure long bearing life. Especially heavy ones. The pulley on an MGC for example must weight 5 pounds. An imbalance can make short work of the bearings, and following that will be the main seal. Certainly not as important as a flywheel or crank though, where a failure can be catastrophic.

Then again, maybe the balanced distributor doesn't mean a physical balance, but rather something to do with the spark or advance?
Steve Simmons

I have never heard of it either. Perhaps balancing the distributor means checking/adjusting the distributor to ensure the points lift at exactly equal intervals? I can understand that being worthwhile because I have seen dizzys which cause "spark scatter" due to bent shaft, worn bearings or worn cam.


I like to convert the top dizzy bearing to a ball race which has zero radial play. Standard bushes need to have clearance which allows a tiny bit of wobble which allows a tiny bit of "spark scatter". I have a stepped bush made because there is no ball race available with an I.D. the exact size of the shaft. The dizzy body has to be machined out to suit the O.D. of the ball race. Using a sealed bearing also keeps the oil down.

Bob Schapel
R L Schapel

From 123 ignition....

Spark balancing
Spark balancing is an advanced technology normally used in Formula 1, where
engine speeds are tremendously high. This technique is built into this distributor.
Its microprocessor constantly monitors the amount of energy contributed by each individual cylinder. Assume for example that the
compression of one cylinder differs from the others. The motion of the flywheel would be less smooth, and so is the motion of the
camshaft. This distributor detects this, and adjusts the timing of each cylinder individually. This results in a much quieter engine,
more power and less wear. Have a look into the following video and watch the regularity the 123ignition fires with, unlike
conventional systems or even well-known breakerless ignition systems:
L E D LaVerne

Wow! That is amazing information. Love what I learn on this site. Perhaps one day we will be able to get a "black box" which will do this for us on our T-Types? Then I will know for sure if the gear-lever rattle on my road TC is caused by the torsional vibration I suspect. I have been meaning for many years to check that dizzy (which is still unmodified and probably a bit worn) for equally spaced spark. (I know that won't fix uneven compressions etc you mention.) Can't see the video but your explanation makes good sense.


Bob Schapel
R L Schapel

Bob, you can get it already today
https://www.123ignition.de/123-ignition-en/ignition-distributor-mg-xpag-tb-tc-td-tf-ya-yb-yt.aspx
I use it sins years on my TD and I'm verry pleased.

By the way, I'm just a satisfied customer.
GK Guenter

I doubt very much that today's F1 engines have a distributor. Its my guess that all timing is done with embedded sensors in the flywheel, however small and light it may be.

However a balanced distributor is not as far fetched as one might think. In early days when ignition was by magneto, racing cars had their magnetos balanced. But the rotating masses were much greater than the shaft in a modern distributor.

Gord Clark
Rockburn, Qué.
Gord Clark

This thread was discussed between 01/06/2018 and 04/06/2018

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