The mouth of the throttle body on the st205 is weird, it's like a rubber bolt on piece that clamps on the other side to the intercooler, mine is kinda worn so I'm wondering what I should use to make a proper mouth and use a silicone joiner, do I need something custom welded up or is there something I can buy cheap or what?

If it needs to be welded, has anyone done this and have the dimensions or a plan? Please post pictures, thanks.

I make billet aluminium adapters that take 2.5" silicone hose, i dont have the time to make any at the moment and have just sold my last one.

I make them all out of one piece of ally and machine it all by hand, then use an "o" ring to seal to the tb surface insted of using a gasket.

another way would be to get a piece of flat plate (6 or 10mm) and weld a piece of 2.5" pipe to it, you would get the same result but i like them being a single peice better as they look better and are stronger.

im assuming you have a fmic? the other option is to use 2 3/4" pipe (i think thats the id of the stock adapter) then keep using your stock one if its still ok.

this gives you a rough idea



FYI i charge $150 for the adapters because like i said they are all hand made, takes a fair few hours and you need a fair chunk of ally when you start to make them.

I want to keep my stock top mount water2air, there isn't a whole lot of clearance there (assuming this is why they have a bolt on rubber joiner instead of a TB mouth.) Will that still fit? I think there is just enough space for a flange plate and less than an inch to fit a clamp on the TB side.

if your keeping the stock wta you only choice is to get another factory one, as there simply isnt the room to have the adapter and silicone hose in between.