B20 cylinder head
 

I require a cylinder head for my 1973 volvo 145 auto to have the hardened exhaust valve seats done to allow me to run unleaded.Would prefer one with larger valves in if at all possible?and also does anyone know of a recommended tuner to port and polish to improve performance?

Regards Keith

just to let you know David Vizard (The God of Cylinder head tuners)

Does not advise polishing of ports it actually make the fuel droplets fall out of the air stream and you could loose power over just porting alone

Search David Vizard Performance you tube al his stuff is on there