not found anything yet…but keep searching…
I had managed to found a China factory can do a titanium exhuast for S1(Which they now produce the exhaust for Merc, BMW and Volks. However i m struggle to find them any spec of the exhaust on the market that can ask them to give a quote to me…any suggestion guys? i m considering ask them to fabricate a style like below but in Titanium 
Looks nice, but they may struggle to replicate those bends on the tail pipes, titanium can be a bit too brittle to bend like that.
If you don’t mind saying, which company have you approached.
is not a company, is a factory that mainly deals with the wholesale. As i know someone in that business so i went and search for them. But i m really struggle as i m only to ask them to produce a one off instead of big production so they are very reluctant to respond and my chinese is not very good so we have a problem in communication too 
Those bend will need to be welded section by section as is titanium and will be too brittle to have that bend
Have you thought about asking Jim??? He likes a challenge!
I had managed to get a reply from other company Revosport which they can do a one off system in titanium but eye watering expensinve… -_-"
If you want a titanium exhaust for the S1 exhaust, we can produce it based on any specs, size of tube and design. If you have no preference, we usually suggest a 15-20% increase in tube size and will replace the main muffler with perhaps 1-2 smaller silencer. Weight will for sure be very significantly lighter than stainless steel.
Expect price to be around US$3900.
Ah, sorry I haven’t had a chance to progress this any further.
A full S1 system from the Cat flange, in Ti;
2.25"dia bore for the system.
Two 180deg bends, plus the tailpipe section (depending on complexity, this part could cost!).
Silencer; 6" or 7"dia? How much noise do you want to make?
I make a GT3 style Titanium silencer for supercharged Toyotas. It’s an 8" x 24" silencer and that size has a serious amount of packing material - by far the heaviest part of the exhaust. I use 0.8mm thick material for the silencer skin - in Stainless or Ti. The finished weight of the Stainless 8x24 is 8.4Kgs - the Ti is 7.9Kgs.
Most Ti silencers I see on the market are on Jap turbo exhausts. When the owner posts that the WHOLE system weighs 4Kgs, I know there’s fck all inside the silencer - helps with the myth you see. No wonder Ti systems sound sht (IMO of course).
Time to manufacture is the problem. I could make 4 Stainless systems in the time to make your one Ti exhaust.
There is NO WAY, I would lobster cut/weld the bends. Japan has many small fabrication outfits. They don’t have the machinery/tooling to bend Ti, so this method is very popular with them - in strict engineering terms, it’s sh*t - sorry.
Saclam, the manufacturer in the pics, does some very nice work but I doubt they’d be interested in a one-off.
So, decide on a silencer size, decide on a tailpipe design and let me know.