Has anyone used this additive?.I am currently using millers VSP but it is quite expensive at £4.0 a bottle and just enough for two tankfuls.
Ihave seen the castrol additive on Ebay and it is much cheaper and comes in syringes that treat 20 litres at a time but not heard of anyone using it.
Paul

Wouldn't it just be cheeper to run on LRP from a garage?

I know its getting rare but Sainsburys and I think Tesco round here still do it

Paul,

I use castrol valvemaster plus octane boost in my engine.

Dunno about ebay but you can buy it by phone; £5.99 a bottle, 6 for £30 from http://www.castrolclassicoils.co.uk/valvemp_new.htm Otherwise it's about £9 a bottle I think from Halfords.
It comes in a 250ml squeezy bottle with a metered measuring neck and treats 250 litres, say 12 tankfuls in my 20L tank. I add it to 97 octane super unleaded - my car was last set up on the rolling road with that fuel so I stuck with it.

I used millers VSP plus before that, which I bought by the 10 pack for £30 from my local motor factor. BTW the r.r.p. is £3.48 per 250ml, or £31 for a 10 pack. So you needn't pay £4 a bottle!

castrol valvemaster plus, phosphorus based - from Halfords cost approx 80p per tankful, i.e. adds 4p per litre to the pump price.
- with a six pack bought direct that comes down to 41p per tankful i.e. it adds 2p per litre on the pump price

millers vsp plus, manganese based - cost £1.50 - £2 per tankful, i.e. adds 7.5p - 10p per litre to the pump price.

I can't comment on relative effectiveness though.




[Edited on 1/5/05 by Dave Ashurst]