Ricardo head spark plug

[Howard Wright]

Hi All

Engine building for my special is nearly complete and while I know I will have to experiment with spark plugs once the car is running does anyone have a recommendation for the following set up?

Standard cam, valves and springs, slipper pistons, Ricardo head (18mm plugs). I have a 1 1/4 SU and will start off with an AN needle and blue spring (again experiment when the car is running).

I understand that the old Speedex site had lots of info but it doesn’t seem to be around anymore.

Cheers

Howard

[Hugh Barnes]

The Speedex site is gradually being migrated to the A7CA.org web site and hopefully, should be available again quite soon...

As far as set up is concerned, if you have a rolling road near to you, that really is the ideal. You can change settings, re-run and get actual measurements of power output etc that will reveal the results of your changes. I set up my Riley 9 on a rolling road, went in with 31bhp at the rear wheels and came out a couple of hours later with 42bhp just for tweaking timing, carbs etc...

[Austin in the Shed]

The Ricardo is not fussy on plugs,I say NGK AB6.I have even used R7's. This has the 14mm hexagon and won't foul on the top of the head when screwed in.

[Howard Wright]

Thanks both

I’ll start off with your suggestion, Austin and I do intend a rolling road session Hugh.

Cheers

Howard