I have performed upgrades in pretty much every corner on the car (I will SCRAP IT if it will not beat and outperform all the Hondas and Acuras over here), except for one area - the exaust.
Having replace the rear muffler with the Ractive type and install a high-flow resonator, the exhaust is pretty much standard 1 3/4", except for the about 70cm long piece of 2" downpipe from the turbo. I did some measurements on the exhaust pipe when I put the car on the stands for the winter, and my hair stood up !!!!! In some place (4) the pipe was squished during the bending process into something just about 1", even smaller.
There is a lot to be improved here. This exhaust on a turbo engine is a definite restriction - the way it is right now it would be sufficient for a 3cyl 600cc engine lmao
My plan is to build my own 2.5" mandrel bent exhaust. I can retain the muffler as the inlet is alredy 2 3/4" and use larger high-flow resonator - or should I drop it??. Right now the tone of the exaust is reasonable, nice deep and noticable. But very bearable on the motorway speeds. What kind of a noise increase am I looking at? Is there anyone out there that runs turbo with the silencer only??
Also, bulding the exhaust itself is not a problem. I have access to the hoist and tools, as well as a friend with very good welding skills. He already did the welds on the intercooler piping.
The question is, what kind of a gain should I be expecting, if much, IF ANY?? The turbo ppl should have an idea here, I hope.
Does anyone have any tips here from their own perspective/experience?
PS: I dont have to worry about the emissions nor MOT