Let’s talk timing, and by that I mean Dizzies……Part 1

[@Darth_Chicken]

Many thanks for these videos. Modern garages don't seem to have a clue when working on classic minis. Took me a while to find someone who actually knew what they were doing.

[@ACDodd]

Just doing my bit to enlighten people.

[@rubencaixeiro9762]

me wanting to learn how to maintain the classic mini I just bought and then I came across your channel.... WOW no way people DIY this at home.

[@mk1leg]

so many differances in 2 sopposed identicle dizzies learning so much watching these vidskeep them coming

[@ToddDunning]

4 months of sheer hell replacing carb and dizzy with Megasquirt. Increasingly questioning why I did it. AC’s points about the advance curve here are the main thing I’ve learned; at each RPM and throttle position combination there is an optimal AFR and advance, and it’s miraculous that needles and mechanical advances have got us through thus far. But only with an expert as we have here.

[@minmog]

Great informative video as usual, looking forward to part two.

[@Rubberduckeee]

This is interesting. Thanks for sharing your knowledge

[@andyfry1970]

Hi AC, Always interesting topics that you put out for the classic mini. And I should imagine that most people don't realise the benefits of the dizzy being optimised for max power and efficiency... as indeed I didn't lol. Great stuff as always 😊

[@keithgarland3404]

If you. Make the videos, I will watch. Always good advice , and sharing your experience with us.

[@tomthompson7400]

perfect timing ,,,, pun intended .

[@allenjames515]

It seems to me that even if the miserable distributor has no wear in shaft, advance pivots, spring anchors it is rotated via slack skew gear and floppy chain. The cam puts a jerky load on the chain so at various rpm is ahead or astern of where theoretically it ought to be. In a BMC A type it does have a damping load - the oil pump, directly on its tail but is a miserable way to ignite engines. I used to walk past traffic waiting at red lights and only a few brand new petrol cars were not splashy and fluttering, contrasting with diesel commercial vehicles. A diesel car was very rare when i was young. I improved my Riley immensely by replacing the Lucas distributor and coil by a Scintilla magneto. The main reason was that the Scintilla auto advance mechanism has friction damping of the interleaved cetrifuge plates. Both systems were gear driven so less backlash in the drive, also Riley used what they called a lag tappet to make cam rotation more uniform - it is a square cam working a follower against a spring and the lobes are halfway between those of the working cams, thus when a real cam is demanding torque to lift the pushrod the lag tappet is pushing the retreating square on the shaft round in the direction required. This thing was to minimise chattering noise from the meshing of timing gear but the first thing Morris Motors did when they bought Riley was to substitute chain for gears, cheaper. NB the chain used is not advised for sprockets exceeding 3,600 rpm. But who cared, the guarantee lasted 12 months or 12,000 mikes whichever was sooner. Note that the Austin Rover K series had a distributor on the end of belt driven shaft, no chain or skew gear slack, it idles perfectly.

[@ACDodd]

Things are a lot better using the later tensioner.

[@kerryminigringo]

Great video Adrian,everyday is a school day. 😊

[@bernardwarr4187]

Great job

[@andrewatkins3219]

Top video AC, filled in a knowledge gap for me as was never sure when you also talked about curves etc, looking forward to part two 👍… you any further with your online training you mentioned a few videos back?

[@ACDodd]

Still working through the training it takes a long time for people to manufacture the tooling and invest in the parts needed.

[@paulhotson5820]

Very well explained. AC, I've watched many Americans with small block engines that recommend total timing all in before 3,000 rpm or less. My question is, should this be applied to all A & A+ engines? Much appreciated.

[@ACDodd]

Much too fast for a road application on an aseries, there are options that need fast to full advance such as boosted applications and some racing types can benefit. But road cars no.

[@paulhotson5820]

@@ACDodd So 3500 is about the limit?

[@ACDodd]

@@paulhotson5820 I won’t give the details as their or too many variables to consider

[@TornadoCAN99]

I've got a '88 mini, originally 998, with a different engine from a previous owner, supposedly a 1275. Having a bit of run-on/dieseling when shutting ignition off and folks have told me could be from incorrect timing. took it to a local classic car shop (not a mini specialist) and they retarded timing from 12 degrees to 8 (I think they meant at idle). Now car runs poorly, no pickup in power/hesitation. Also cold starts it will not keep running without foot on throttle for first 5 or 6 minutes. Have since discovered the vacuum advance servo is leaking, not holding vacuum when I suck on it. Looking for a source to get a good used/new advance unit (hard to find here in Canada). Then I will get the timing sorted....but not knowing what engine/cam etc, I'm unsure what to set it to (dizzy is 59D4, with Pertronix Ignitor EI/Coil). Sure wish there was an AC Dodd over here ;-)

[@ACDodd]

I will be doing remote tuning in the future over video call. Watch this space. Use minispares in the uk for a vacuum can.

[@TornadoCAN99]

@@ACDodd Will do. Getting stuff here from MiniSpares is dreadfully $$$ as they do not give an option for postal delivery, just DHL. So have to factor in $40-$90 more plus tax, then expect another $30 in "added brokerage" fees from DHL once they get hold of the package.

[@StefanMiniCooper]

Nice video again! I have the luxery that I have the 123 ignition dizzy so I can choose different advances. I heard that you made this curves for 123. Which curve is for you the 'fast road' type AC?

[@ACDodd]

Yes I did supply curves for the 123, curve 6 is a good place to start

[@StefanMiniCooper]

@@ACDodd thanks! On the moment I have curve 1 which haves 28 degrees max. But pulling really good in all the rev ranges (1293 with modded head and kent 266 shaft) I keep it in mind to test with curve 6.

[@ACDodd]

@@StefanMiniCooper check it with a strobe to ensure you have what you think it should be

[@theovanrooyen5553]

hi