Had the plugs out of the SD1 for the first time in a few years. And it's
> been running on Optimax for the last year or so. I've never seen plugs so
> clean - the insulators were near white with no deposits on them at all.
> How are you meant to tell if the mixture is ok these days...;-)
>
> I've fitted Bosch 4 plus, although they don't list them for the EFI. But
> they do for the TVR 350i and Range Rover EFi of the same age, so I'm
> hoping they're the right ones.
>
> --
What kind of driving - is it mainly motorway stuff ? I always found that the kind of driving made a huge difference to plug deposits - course these days you dont get to look for at least 50k miles ( main dealer service schedule..... ) :-)
Steve