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I am still trying to improve the fuel consumption of my Suffolk SS100 I am now considering fitting electronic ignition to my XK 4.2 engine. I would be grateful if contributors to this forum could tell me what they have fitted (or not) and also tell me if it has been of any benefit.

I posted this in the general area of the Replica BB because most of use XK 4.2 engine

Thanks

Hello Neil,

When I bought my SS it was fitted with a 123 dizzy however, it was never really that good so the factory chaps fitted a H&H which seems to be far better. The car starts and runs better, the fuel consumption is around 23mpg ( provided I don't drive it like I stole it ) and it has a black cap which looks a little better than the red one on the 123.
I expect Roy can throw more light on the subject but I hope this is of some help.
By the by, is that Steve's car I see for sale on Rogers site?

Reg

Neil,
OK, ignore my last comment, I have just had an e-mail from Steve who told me that he has sold his SS back to Roger and he has bought an XK120.

Reg

Hello Neil,

I would be surprised if electronic ignition made any noticeable difference in fuel consumption, why would it?

Apart from having the engine in the best possible tune, possibly setting the mixture slightly weak, the most noticeable effect on consumption is driving technique.

Alec

Alec
It is the old chestnut of getting the engine in the best possible tune, poor timing, incorrect dwell angle and wrong points gap can have a great influence on the fuel consumption, I am told, but you are right driving style is also important. Alas, despite an economic driving style my fuel consumption is still not what I would like it to be and I am sure some of the problems are due to the poor timing

After looking at lots of options I have taken the plunge and fitted a Powerspark distributor with a high power Electronic ignition unit and high power coil. This was easy to fit and not too expensive, in all, the new dizzy, coil and new plug leads cost about £130.
I took Ken Jenkins advice and set it to 24 degree BTDC with the vacuum off and since fitting it I have seen an improvement in fuel consumption and my car is running very smoothly.