The Lotus Grand Tourers

Hi everyone!

The Lucas distributor of my '89 Excel SE with the HC engine is worn out and together with my garage, we decided to go for a 123 distributor instead. I also asked 123 to put a map on it upfront by providing them with the various info I found in this forum and in other places in the web.

However, somehow that mapping is not ideal; according to my mechanic car is not running fine. Everything else has been replaced in the meantime (petrol pump, petrol line, HT leads, spark plugs, carbs have been revised; so it seems to be a problem with the mapping.

Is there anyone with a 123 distributor on a HC engine, which could provide me with curves for mechanical and vacuum advance?? We just need a proper starting point; maybe I try a finetuning on a dyno in another place later.

She is now sitting in the garage for months; it´s pretty frustrating......Any help is highly appreciated!

Thanks a lot!

Georg

I THINK these are the ones that appear to be working ok on mine. Might be a starting point. Can’t confirm, as the engine is hiding and everything disconnected at the moment, as can be seen in last photo!

Hi Alan,

thank you so much for the info! That will be certainly be very helpful!

I will give some feedback once my mechanic has her ready for the road again

Georg

Looking at the timing in the service notes, you should use the following:

Static timing: 10 degrees btdc
Idle (hot) 950 rpm: 10 degrees btdc
2000 rpm: 18 degrees btdc
3000 rpm: 26 degrees btdc
Ignition timing to be set at 28 degrees btdc at 3500-4000 rpm

N.B. All above with vacuum disconnected.

The vacuum advance is up to 22 degrees (presumably max vacuum, but there is no specification for setting this)

Hope this helps

Cheers

Richard