Technical 903cc distributor advance curve

[ernied]

Hi, does anyone know where I can find the distributor advance curve for the 903cc (100GBC) engine.
Ive got a “123 ignition“ distributor and I’m setting up the curve.
I know that the static advance is 10 degrees and centrifugal advance is 28 degrees
but it would be good to know the steps in between and at what RPM the total advance should be.
I hope someone can help. Thanks

 

[Gary50]

Hi @ernied,
I fitted a 123 Ignition to my 900T Amigo Camper about 3 years ago, I'll see if I can dig out the information on how I set mine up.
From memory I just set the static advance and let the dizzy do the rest. The van hasn't been on the road much (as we moved house shortly after) but the 123-dizzy coupled with an electric fuel pump means very easy starting even when sat idle for months on end.

If you haven't already downloaded the app I'd recommend it as it gives useful information and you can tweak the settings in it and it makes for a very useful immobiliser.

 

[ernied]

Hi Gary,
Thanks for the reply. I’m at the end of a restoration on my 1969 850 sport coupe and I’ve also
installed an electric fuel pump as well. My “123” dizzy is a tune USB and I’ve got the program
set up on my laptop and just wondering where to set the different points of advance and
at what RPM.
Thanks again,
Cheers, Ernie

 

[Gary50]

Hi Gary,
Thanks for the reply. I’m at the end of a restoration on my 1969 850 sport coupe and I’ve also
installed an electric fuel pump as well. My “123” dizzy is a tune USB and I’ve got the program
set up on my laptop and just wondering where to set the different points of advance and
at what RPM.
Thanks again,
Cheers, Ernie

Hi Ernie,
Sorry for the delayed reply, I've not been able to work on Connie for sometime.

I've attached the 123+ installation manual (the version I used).
From the Haynes manual I have the following settings.
Static advance 5 to 7 degrees BTDC
Centrifugal advance 28 degrees plus/minus 2 degrees max.

I've left everything else as standard and it seems to run okay.
It was a few years ago since I installed the 123 dizzy and the only journey Connie has made is when we relocated... a journey of 60 miles (2.5 years ago).

There used to be a few garages in the UK that knew how to tweak these and it's been on my to do list to find one and get them to fine tune my set up - although Ideally, I'd like to fit the twin choke carb I've had sitting in a box for ages first.

Hope this helps a bit.

Cheers
Gary

 

[ernied]

Hi Ernie,
Sorry for the delayed reply, I've not been able to work on Connie for sometime.

I've attached the 123+ installation manual (the version I used).
From the Haynes manual I have the following settings.
Static advance 5 to 7 degrees BTDC
Centrifugal advance 28 degrees plus/minus 2 degrees max.

I've left everything else as standard and it seems to run okay.
It was a few years ago since I installed the 123 dizzy and the only journey Connie has made is when we relocated... a journey of 60 miles (2.5 years ago).

There used to be a few garages in the UK that knew how to tweak these and it's been on my to do list to find one and get them to fine tune my set up - although Ideally, I'd like to fit the twin choke carb I've had sitting in a box for ages first.

Hope this helps a bit.

Cheers
Gary

Thanks Gary, much appreciated. I’m looking forward to tinkering with the advance settings.
Cheers, Ernie