I have a ST 170 head that I want to get gas flowed (polished & ported) can anyone recommend a company to carry this out? I’m in West Sussex.

Dunnell Engines?

you could also try Scholar Engines http://www.scholarengines.co.uk/

both Scholar and Dunnell are in/near Stowmarket Suffolk.

Have a look round the Ditchling area (could be the industrial estate)
I'm sure that there was someone local.

Other wise I'd say Dunnell, but its a trek.

Is there no-one in Guildford area?

Vulcan engineering , just off the M20 specialise in Ford engine and heads

Having just had an ST170 engine in for quick check over that had received head work by a company listed above, Id simply say just deal with CNC heads.
couldn't fault there work on a customers engine i rebuilt last month.

Neil Roper you wont get better and hes not as expensive as you may think. Lot oh engine builders use his heads

Get hold of A.L Developments, he did a good job on my zetec head, it was 2-3 weeks turnaround, he also fitted a set of valve guides and ported/matched the inlet to the head at a very reasonable rate.

Have a look at his work here:
https://www.facebook.com/AL-Developments-846552508744383/
If you're not on facebook, i can pm his email address.

Dave

Thanks all, I will make some calls