help with ignition timing pulling all my hair out
Turbo Mini Forums

I have just rebuilt my 1275 mini engine.I am trying to petit to run properly and am scratching my head and can not fathem it .I have installed the 286 cam with a duplex and ligned up the dots and. Checked with a dial gauge.The dizzy drive installed and rotor arm points to no 1 plug.I have a 59d dizzy with accu spark unit fitted.The car starts and runs quite roughly but when I connect my strobe it shows about 40 degrees before tdc as the sparking position as my strobe has a dial I can change the advance .When I try to move the dizzy to about 10 degrees it stalls and stops.

Any ideas before I burn it

Chris

Can you get away with just lining the dots on a 286? I would have thought it needed to be dialed in more accurately than that.

I'm sure someone will know

Yeahthought about that and still would not make it 30-40 degrees out

I'd say cam timing as the dizzy drive comes off it, if the cam timing is out then up to a point the ignition timing will be out. Valves etc not closing at the right time coupled with the expansion of ignition etc will cause it to run like crap. One you retime the cam you may find you only have to move the drive round a notch but it'll make all the difference. Dot to dot is only good for standard cams really, I'd even time in an mg metro cam better than that.

theres a guide on here for timing the cam which is a good read

Done now needs redoing lol

check your top dead centre mark on the crank pulley is correct.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

That's another point, there were two on an engine i recently put together, 180 degrees apart :/

Mine runs at 21° of advance if I try to go as low as you have it will have none of it. Before you Go rippling your engine apart try running it at 18°of advance first and seed how she runs. You said you used a Dti was that to get tdc or valve position?

Own the day

Also your going to hate the way it drives with a 286 cam I can't emphasise this enough

Own the day

As with Mr Joshua, try running static at around the 20 degree mark. some bathtubbed type cylinder shapes need more time to get to the squish point, but curve after that should be normal ( so full advance of around plus 20)

Edited by Earwax on 4th Aug, 2013.

Just double checked the cam timing and it appears to be 20 degrees out at the crank which would give 40 at the cam and ignition. Feel like a idiot, but going to Re time this afternoon and fingers crossed .

Will post when have retired, and thanks for all the help

Chris

Its a wonder it ran at all then! thats over a tooth out!

Set cam to 106, new points installed, all checked over and ready for starting in the morning as the neighbours would kick off if I let rip.now
Fingers crossed

Chris

is it started yet?

Done now needs redoing lol