Morris Minor Owners Club

can you use it in cars with an unleaded head? and if not what is a good petrol additive for cars with unleaded heads?

You don't need to use any additive in cars that have unleaded heads.
If you did use Valvemester it would do no harm.
If you use 'Valvemaster Plus' you can benefit from the octane boost, but it's not the only octane booster on the market, and apart from people with highly tuned engines, I've not known anyone bother with octane booster additives.

The only additive that actually contains tetra-ethyl lead - is TETRABOOST. It completely replicates the original leaded petrol. The others all use various potions - sodium/potassium based I believe - some have found their exhaust valves to still fail despite using these potions. (Is that better Mr MOD? At least it's encouraging to see that someone reads my posts!)
Tetra is not cheap - but it makes true leaded petrol when mixed in the correct proportions. It MUST NOT go anyhwere near a catalyst!! So if you mix up a spare gallon, do not be tempted to use that gallon in a modern car - or it's bye-bye catalyst.

BMC, have you got any link to Tetraboost? That's the second post this evening recommending them
I looked at their website but found no information about stockists, and they say a "box" is 120 quid but give no clues as to how much you get for that.

Any additives recommended by the FHBVC will be absolutely fine. I use Castrol Valvemaster Plus as it's easy to get hold of.

Sorry - I don't use Tetra myself - it's just the only one with genuine LEAD. Is there no link from the website ? Despite the FHBVC tests - which in some peoples' view did not replicate true road running conditions - some people are still finding their exhaust valves and seats failing. Two on here very recently!

BMC can you use valve master in an unleaded head and have good results in preventing burnt valves in the future?

No idea mate - I would guess it's a waste of money. Un leaded head should be able to take everything thrown at it (but it seems they sometimes don't!) - and note the fuel in US of A is even lower octane rating then here - but it is half the price!!

yeah what you think i should do? use an additive or leave it and run highest octane stuff i can get?

some have found their exhaust valves to still fail despite using these potions.

Some have found their valves to fail when running on fully leaded petrol too (I presume you remember the 70's and 80's)
The FBHVC testing showed clearly that some additives were very good at preventing VSR and others were not. Some additives gave no protecion when compared to no additive at all. Some people ignore the results and use an additive based on price etc...
Valvemaster did extremely well in the tests, which speaks for itself.

Mr MOD? At least it's encouraging to see that someone reads my posts!

Thanks for the encouragement - it makes a change from our troll/s complaining about any and all Moderator action ;-)

Keep up the good work Mr MOD !! Ben - use the best fuel you can get (it's still going to be dirt cheap) - and keep an eagle eye on those clearances. Yes Ray - valves have always burned out - and I agree - the pie slice shaped burn does suggest a metallurgical fault. But i still think some 'unleaded' heads are being sold with cheapo valves !