Powered by a 204bhp 2.5-litre V6 petrol engine, the IS 250 SR will accelerate to 62mph in 8.1 seconds - 8.4 with the optional six-speed automatic transmission - and top out in excess of 140mph.
The IS 250 SR's full bodykit includes 17-inch 10-spoke alloy wheels, deep all-around skirts and a rear spoiler. Inside there's aluminium scuff plates and pedals. Five-spoke 18-inch Tsuki rims are available as an option.
Included as standard are heated front seats, ten airbags, climate control, cruise control, smart keyless entry and engine start and sequenced LED interior lighting. Lexus says the IS 250 SR adds £3,500 of kit to the IS 250 donor model for a premium of less than £1K.
Three exterior colours are available - Velvet Black and Cadoxton Slate and Argento Ice metallic finishes - with a Worcester Black interior fabric trim.