thanks for the warning i will keep an eye on it.
so far so good it is still running sweet as a nut,
the car performs better than it ever did im certain it was low on compression before the rebuild
thanks once again for all the help/advice

 

How were the tops of the pistons??
All of the Mines Rom's I've seen have timing advanced off the charts which is not safe on anything less than 103+ octane fuel.

 

when i got the head off at first glance piston 1 and 2 looked fine, piston 3 was slightly pitted and piston 4 was the worst.
It had melted and welded itself to everything, piston 4 also had welded the rings together and scored a line down the bore, the block was honed as best as could be then 4 brand new pistons and rings were fitted to the old con rods
it was only when i got 1 and 2 out that i found the ringland had failed and cracked,
where as piston 3 and 4 had melted rather than cracking.

the problem was the car had regulair unleaded 95 ron in the tank when it was hammered down santa pod leading to detonation before the piston was at tdc i think thats what cracked 1 and 2 were as 3 and 4 was running too hot.

the car is now run on momentum 99 ron 80% of the time only if the car gets low nowhere near a tesco does it get shells 97 ron vpower.
this was piston 4
http://www.flickr.com/photos/14937501@N08/5535709061/