Battery charged overnight, turns out it wasn't the battery that was the problem. It was my overly enthusiastic crimping. I swapped the tacho signal wire for shielded wire in an effort to cure my flickering speedo, exposed the shielding and crimped a wire over to connect to earth. Unknown to me, unfortunately the ferrule thingy I chose for crimping had bitten right down through the shield into the signal wire, effectively earthing the coil, which would explain why on trying to start some of the needles on various gauges were flickering.
Stripped the wire back, left the shield disconnected and it started first time! The shield was still connected at the tacho end, just not at the dizzy end, which seems to be good enough as the speedo is now steady so I hope that's cured now.
We had no real idea what the total mech advance from the Moroso advance kit was, the paper booklet that came with it said 23° but I was skeptical of this as various sources I had read said the weight and centre plate combo in the Moroso kit gives around 15° mech advance. I tried to measure it with pen marks on some tape stuck to the rotor and reckoned it was about 18-19ish. I was hoping that whatever it was, it was towards 15 so I could use more initial advance. I made one last check before getting the timing light out that the advance mechanism was working smoothly and not binding on the inside of the rotor like the nasty Accel kit that I fitted. Everything seemed fine.
Naomi is now an expert setting timing, I was in the car watching the revs and she was on the light. We fired up the car and set the initial at 16°, had to open up the idle speed a hair and richen up the idle screws and it just scraped 10 in.hg at 900rpm. I then raised the revs in roughly 500rpm stages so we could see what the curve looked like. My spring combo was weak/medium. 15° was steady at idle (so the centrifugal advance wasn't coming in at idle revs = springs not too light). The timing started coming in at about 1100-1200rpm and peaked out at around 29/30 degrees at 2800rpm. We took it briefly to 4000 (very loud in our single car brick garage!) to make sure there wasn't any extra surprise timing hiding in the mechanism and it had truly levelled off and it was still 30° at 4000rpm.
We've got new neighbours who have seen the car but never heard it, fortunately they approve!
This would suggest the 15° figure I had read somewhere (can't remember where) was correct. Seems odd that on the booklet that comes with the kit it says 23°. Interestingly Naomi checked the timing on the damper marker (no dial-back on the timing light) and got 14° but when she dialled in advance on the light to get the marker to 0 on the damper, it read 15/16°. I'll try and find a garage with a good timing light to verify things.
I know that 30° all in is a bit short of the optimum for peak power but at least it was running and it hadn't turned a wheel for nearly 6 weeks so I went for a short drive. I got to the end of our road (50 yards) and promptly ran out of fuel, d'oh!
5 litres of British Petroleum's finest 98 octane and we were rolling again. With the exhaust leak now fixed, the true AF ratio revealed itself to be... very rich! It was running between 12.5 and 12.8 cruise. Very boggy, sounded like pan of water on a rolling boil. Not much zip, felt a bit sluggish but at least it works.
The lean spot on part throttle is still there but I only drove it 6 miles or so I can't yet decide if drilling the idle jets has worked or not, first thing is to verify the timing, get it to something more like 34° all in, lean off the primaries to something sensible, then I reckon I can close the idle speed back down and see if the transition circuit is performing any better.
One thing I did notice while driving it, the water temp is still pretty high when below 40mph, it was mid 90's (celsius). I know my rad is good enough, all my hoses are the same as most others but I'm pretty sure it should be able to run 88-90°C (195F). I have previously played around with my infra red temperature gauge and I compared the top and bottom temps of the rad which showed the rad is definitely doing its job. This lead me to think there could be a restriction in the system somewhere. One thing to think about is - I wonder if my heater bypass might be too much of a restriction. It came off a Ford Puma and probably has a much lower flow rate requirement. The other alternative is that the bleed-off back to the header could be too large so the water is bypassing the rad. Anyway, more pressing matters at the mo, back to the carb setup!
Edit - high temperature was caused by retarded timing. I set the timing up correctly and the temperature came down.
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