Cylinder head thread inserts

please could I ask for opinions/advice on which type of thread inserts would be best for the 3/8 studs in the cylinder head that strip/pull out, ie helicoil, silicon bronze, t-serts etc, any info would be appreciated.

Thanks,   Ralph. 

I had a number of stripped cylinder head threads repaired with both helicoils and brass inserts.  The helicoils were the cheaper of the fixes but a couple eventually came loose due to yearly head servicing taking its toll.

The brass inserts never gave any problems but each cost 3 times the price of a helicoil.

I was able to find local engineering companies to do this kind of job. For other more serious cylinder head problems I used to go to  BLR Engineering Hersham, Surrey who have many years of experience in dealing with Nortons.

Hi Ralph

Just a Note to support Phil's comment above. I can also vouch for Ian Mole's work at BLR. Incidentally he has recently taken over Len Paterson's 'Cylinder Head Shop' and is now based in Wallington, Surrey.  Contact Ian at http://www.blrengineering.co.uk

Here's a relevant pic attached of Ian's work on a Commando Head?

thanks very much Phil and Peter for your input , cheers   Ralph.