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Is This Head Unleaded Ready?


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Thanks for the reply.

So what do I have to do to run it on leaded as its been a long time since I saw four star on the forecourt lol. The car is up and running now for the first time in ten years but on unleaded ?

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I use a lead substitute additive such as type branded castrol, normally costs around £11 ish & is suitable for about 5 fill ups.

Some people don't bother & will tell you that using unleaded hasn't affected their car for the last few years, the problem is that the soft older style valve seats erode gradually & you wont notice any problem until a loss of compression causes problems & its head off time.

Another usefull tip recently published in a classic car paper was that it is better to use Super unleaded in cars over 25 years old as it does not (yet) contain the ethanol content that can damage fuel lines on older cars.

Also i have found that because of the higher octane rating both my Alpine & Manta which were designed to run on 98 octane petrol seem to run better on super unleaded at 97 octane with Shell V max at 99 octane the best.

Because i dont use my classics as daily drivers the difference in cost by using lead addidtive & Super unleaded is "relatively" affordable.

Plus if i am minimising valve seat erosion & hopefully stopping fuel line damage then thats a bonus.

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A lot of the octane stuff is pure placebo and people think it runs better or faster.

For example if you have your timing retarded to run unleaded, it is only retarded due to the lower octane not the lack of lead. If you leave it retarded and put high octane fuel in you are effectively lighting the mixture too late.

Lots of people don't realise that the same is due with octane boosters too, unless the car is timed for higher octane they run slower with higher octane fuel.

Lead substitute of course is a different issue, you still need the timing to be apprpriate to the octane.

If you remember when leaded went out there were articles saying old cars had enough residual lead in the fuel system to last 20K to 30K miles or something (no guarantee, check for yourselves)

However, a million gallons of unleaded are kept in the UK each year for classis use. You just have to look up the petrol sations with it.

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