Grimmspeed 003001 Uppipes

• Subaru STi (04 and up).

Built for the (04 and up) Subaru STi... Due to emission regulations, Subaru has put restrictive catalytic converters in the exhaust system. These restrictive catalytic converters do not allow for optimal exhaust flow to the turbo, thus top performance of the exhaust system cannot be achieved. Also, removal of the catalytic converter helps prevent the possibility of damaging the turbo if the catalytic converter breaks apart. GrimmSpeed s Up-Pipe eliminates the restrictive catalytic converter and provides a larger diameter pipe that helps spool the turbo in a quick and efficient manner. There is a 10+ whp gain when using the Up-Pipe.The GrimmSpeed Up-Pipe is specifically created without an EGT bung. An EGT sensor is not necessary. If you would like to keep tabs on EGT temperatures the correct place to do it is on the exhaust manifold right after the exhaust ports, this is the only place where the correct temperatures can be taken.FeaturesQuality Flex Joint - Grimmspeed has sold more over 600 pipes with flex joints and have never had an issue with any of their pipes. Flow through Flex - There are no big steps in the flow path of our flex joint. Their flex is not located on a bend so there is very minimal flow loss(if any) through the flex. 2.0mm Piping Thickness - almost all pipes on the market use a 1.5mm thick piping wall, not Grimmspeed. They use a 2mm thick piping wall(33% thicker than all of their competition!) Pipe to Flange Connection - Much smoother connection. Piping is ported flush with flange so there is no step into the pipe.1.92" Inlet = perfect match to ket allowing a little room for ket movement(anything bigger, ie 2", will almost be guaranteed to put the ket in the flow which is horrible for flow)1.75" Outlet = Narrowing down from 1.92 to 1.75 acts as a funnel. Also very close match to most common turbos so you have much less step going into the turbo(unlike a straight through 2" which creates a huge step going into most common turbos vf's, tdo