I've been using a fuel additive, made by Nulon (cannot remember it's name - costs about $15 for a litre) for the past two years with premium unleaded and have had no problems.

$15 for peace of mind is worth it in my books - and a bottle will last you close to a year if you fill up once a week.

The only thing that I have noticed is that my plugs seem to foul a bit quicker than before... can anyone shed any light on that one for me?

I can confirm that L series are fine on unleaded.

According to the info i had read recently, the valve seats in 1000's & 1200's are aluminium bronze alloy for the inlets & cast iron for the exhausts. If this is true, then it would be wise to slip in a squirt of valve seat lube at tank top up time.

Unleaded fuel is specificly recomended against for use in L series engines in the fuel company literature that i have studied here in Australia. Lead replacement fuel was specificly recomended.
Unfortunately i can not bring to mind the source material for the Datsun 1000 & 1200 valve seat material at this moment.

alloy head = hardened valve seat inserts generally.

Both L Series and A Series are fine on unleaded. They run a little hotter on a freeway at sustained 4000 revs.

Chris

I have looked into this subject and the A12 engine runs fine on unleaded fuel . There is a website all about unleaded fuels and older cars .
Just do a search on the left in the menu .

Hi
Another question..
When you do an engine rebuild with a view to running unleaded fuel or premium - are there any special things you need to take into consideration, like valve's, valve seats etc etc. If so, what names, or brands need to be used.
Thanks a lot.