How do you think this inlet would compare to a ST inlet in volume and why didn't the 500 inlet have issues around the neck area like the 2wd??

Seems a decent price with a little finishing with an additional 25mm depth over the RS500 casting with the 4 extra holes welded up

http://cgi.ebay.co.uk/Cosworth-Sierra-Sapphire-RS500-EIGHT-INJECTOR-PLENUM-/140498666752?pt=UK_CarsParts_Vehicles_CarParts_SM& hash=item20b65f8500