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RE: Timing Wierdness...

To: Bob Lang <>,,
Subject: RE: Timing Wierdness...
From: Bill Babcock <>
Date: Fri, 23 Oct 1998 14:14:10 -0700
Your distributor cap has little or nothing to do with timing for an
individual cylinder--it's the cam lobe that actuates the points that
decides timing. No big surprise that your timing is off if you have a
lucas distributor. The bushings are questionable, and the machining is
imprecise. You could also have a bent distributor shaft and/or worn
lobes. I don't know how many lobes the distributor has on a six cylinder
engine, but the critical question is whether or not the same lobe
triggers the 1 and 6 spark. The answer is probably not.

-----Original Message-----
From: Bob Lang [mailto:LANG@ISIS.MIT.EDU]
Sent: Friday, October 23, 1998 12:34 PM
Subject: Timing Wierdness...


I've been playing with timing lights on my TR6... it's running better 
now, but there's still a little "miss" on steady throttle - no doubt a 
vacuum leak somewhere, but things are generally better.

And now the Triumph driving season marches toward the end-o-year...

At any rate, while poking around looking for reasons for some slight 
mis-fires, I wound up placing the timing light pickup on each of the 6 
spark plug leads to see if there was some wierdness going on there. I
not find anything wrong - the spark is very good to all six swilinders.

I did observe something that was a little strange, however.

Cyls. 1 and 6 are 360 out of phase... so I figure that putting a timing 
lite onto the plug wire for 6 should show up on the crank pulley with
same timing... right?

Well, it looks like my cylinder 6 is about 4 degrees retarded from 
cylinder 1. That is wierd. I changed to another distributor cap,
that maybe my cap had some carbon tracking in there that was throwing 
things off, but the indication was exactly the same with a brand-new

Anybody have an educated guess as to why one cylinder might have the 
ignition retarded by 4 degrees or so??? I know that VW did this on the 
Type 1 to help cylinder 3 run a little cooler, but that was an
engine... but a TR6???

Enquiring minds want to know. And TIA

Bob Lang                Room N42-140Q          | This space for rent.
Consultant              MIT Computer Services  |        
Voice: (617)253-7438    FAX: (617)258-9535     |

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