The Bentley T1 Saloon model was introduced to the UK market in 1965. Based on the Rolls-Royce Silver Shadow I body – the only exterior components that differed the two models being the front grille – the T1 featured a lightweight body shell and was fitted with a powerful 6.23-litre V8 unit. The Bentley T1 Saloon was designed by James Young and Mulliner Park Ward and initially appeared in a 4-door saloon variant. Two years later, a 2-door convertible body style was added to the T2 range. Standard features on the T1 included electric windows and adjustable front seats.

The S3 looked very similar to the S2. The most-visible difference was a new turn indicator light in the nose rather than on the side, along with a four-headlamp layout that paved the way for the radically new Bentley T1 in 1965, a lower bonnet line and an altered grille. The interior was modified with individual seats for front passengers and increased leg room in the rear. The S3 continued the 6.2 L (6230 cc/380 in³) V8 engine introduced with the S2 but the carbs were larger and the induction system and compression ratios were modified. The power steering was also improved.