Right! Im THE Clio 16V geek, so print this off for your info Chris! as Im sure youll know, car ranges change a lot over time, but heres the 16V-specific basics:
Late 1991 to late(ish) 1992 (J to K-plate): Phase 1 Clio 16V introduced in UK. Was introduced earlier in Europe as the homologation car for Renaultsports Group A rally campaign (yes, that was the same category as the Integrale, Cossie etc!). Car has 137bhp 1764cc F7P engine as seen in 19 16V. Many differences over standard Clio, including flared arches (plastic front), bigger bumpers, bonnet bulge to allow clearance for inlet manifold and air vent for exhaust manifold. Very first UK batch came without a cat (like 500 cars tops). 16Vs from late 1991 to late 1992 came with an interior chequered with Renaultsports logo at the time and the logo was also found on the door tops, above the locks. All Phase 1 16Vs came with "Turbine" 15" polished alloys and thin bump strips all round. Badges read "16V" next to the side repeaters and on the boot next to "Clio". Leather interior is an option (with different 19 16V front seats, but in grey, not black). Very early cars also have a different alternator (mainly not sold in UK market). Pop-up manual sunroof.
Late 1992 to early 1994 (K to late L-plate): Standard interior changed from Renaultsport logo chequer to a kind of greeny/grey slashes effect. Some rare colours come and go during this time, including metallic green and ultra-rare Tungsten Grey. Now with electric tilt/slide sunroof.
March 1994 (late L-plate): Clio 16V gets Phase 2 treatment, in line with rest of range. No mechanical differences worthy of note, apart from soft five-spoke Speedline "Vega" 15" alloys. Phase 2 gets side impact bars and seatbelt pretensioners, but NO drivers airbag until later in 1994. Also bigger side bump strips (incorporating "16V" badge), reflective lower boot strip, clear front fog lights (Phase 1 are yellow), slimmer Valeo rear wiper, slightly bigger mirrors and a rounded front grille bar. Phase 2 front seats now based on 19 16V units, with grey velour material. Introducion of Naples Red metallic and deletion of older paint options.
September 1994 (early M-plate): Now with drivers airbag as standard. Monaco blue paint available (later also found on Williams 3). But dash-top and glove-box door now covered in slightly less quality and less padded material.
May 1995 (late M-plate): Optional CD player.
Early 1996 (N-plate): 16V discontinued. Introduction of Phase 3 Clio (still Mk1 though, but with more body changes).