Ignition timing on twin cam

[el torro]

Hi after any years of restoring/ rebuild of my elan +2,1973,130s/5 it is now road legal,however crank pulley does not have TDC marked on it,does the screwdriver in no 1 cylinder method accurate,if so using strobe light indicates it is fire ing after top dead centre,engine starts easily put does not drive well,need advice on rectifying this,or preferably some one who lives in Edinburgh area to assist/ or mobile lotus expert,I really want to start enjoying it,many thanks John

[dougal9887]

A dial gauge will give better accuracy. There is a dwell angle of about 10deg so for best accuracy the crank position should be marked at the same piston depth BTDC & ATDC, the centre of these positions being TDC. A timing dial fixed to the pulley is the usual way to do this but the plus 2 really needs the radiator removed to make this easier. The centre of a couple of marks on the pulley should be adequate. Also , in my experience, better to use a standard strobe then there is no doubt about what position is being shown. (This won't apply to an expensive dial back type!).
I'm in the Glasgow area and would be happy to help but maybe too far from you.
Dougal.

[Concrete-crusher]

I would suggest finding TDC as you say with a rod placed in no 1 cylinder and a dual gauge. But you also need a degree wheel and measure either side of Tdc taking the average value , then put a mark on the crank.

I found with my engine that when the timing was off it would not pull i.e. Felt like no power. The other thing to check while you at it is the valve timing , I ended up using the variable sprockets , it made a huge difference.

Sorry I'm not in Edinburgh otherwise would be happy to help

Steve

[Mr.Gale]

You need one of these.

Mr.Gale

[elansprint71]

If you don't have adjustable valve-timing sprockets, take it to the nearest rolling-road tuner who knows what he is messing with.

[el torro]

Thanks for replies,dial gauge it is ,never thought of that and have used one before,just have to borrow it again if person will let me

[alan.barker]

If there is no tdc mark on the pulley how were the cams positioned before
Alan

[el torro]

I bought this car in bits,engine was shrunk wrapped as it had been rebuilt for PO by guy in rugby,the cam /valve timing was done then,the crank pulleys and others were converted to flat toothed belt system whitch was off engine,I put it back to v belt system,it has been a long haul restoration ,the diff all suspension etc is new old stock,drive shaft spyder conversion,no more lotus restoration projects for me ,age take its toll