Just done a new responsive web site for BTB Exhausts.
We have used BTB exhausts a number of times to create bespoke exhausts on a number of memorable cars we have had including:
BMW 2002 with race engine running on twin 50's - James still runs this
BMW E30 2.7 with Eaton M90 blower from a DB7 - you will never have heard anything like this! - CLICK HERE FOR YOUTUBE VIDEO
BMW M3 3.2 Evo Saloon - RIP!
BMW E90 M3 V8 - sounds fantastic - no drone and a fabulous howl from 4k-8.3k - off throttle as quiet as standard
and currently BTB have our naughty and noisy Caterham Cosworth BDG 7 which in a feat of exhaust system engineering - have managed to get it down to 103.5 DB at 4500 rpm with a side exhaust - so should be able to get it out on some noisy days on track in 2015. They could reduce it further but i do not want to sacrifice missing out on the heavenly sound of the cosworth bdg motor at full chat
Away from Racecar's stuff - they have also deal with some low rent historic stuff ;) like Ferrari 250 GTO, Mclaren F1 GTR, Lola T70, Ford GT40, and just about every derivative of Porsche 911 RS/R/GT3 etc
They also do small volume specialist OEM manufacturer stuff aswell as modern race stuff and have recently provided exhaust system solutions for BTCC title winning cars.
Basically of you want the most power and/or need to adhere to noise regulations - BTB get the job done.
Away from all the corporate stuff - Joe - who runs the business is also a bit of a petrol head and runs a heavily modified Lotus Carlton which in the Nevada Silver State road race AVERAGED(!) 160 mph for 90 miles on public roads - nutcase!