Tomei designed the headers to be the 4-2-1 layout with 42.7mm, 45mm, 60mm sizes to help extract the absolute maximum from your EJ25 turbine with the equal length design. The exhaust pressure is controlled best by this layout and you can see the peak power gains at high RPM.
The lost wax process was used to eliminate cracking from welded weak points and for aiding smooth exhaust gas flow with out any interference.You will have a new higher pitched racing sound from the isometric design. With 2.5mm thick pipes made from SUS304 Stainless Steel.
congrats, you now have a 3 bolt setup! if you want to make it an external wastegate, grimmspeed is a great combo with tial mvs 38!
My favorite is the 3 bolt up pipe you get with this. Always had trouble with 2 bolt style.. But I'm rough on cars.
i love these headers best money spent on these headers. I ceramic coated them and heat wrapped them. Defintely feel the difference on my wrx sti
- Good quality header, doesn't feel cheap.
- The included wrap is enough to wrap the pipes individually and is very good quality. I've driven the car 6 months in varying weather and the wrap still looks very good (OEM splash guard is installed).
- Separating the slip joints for fitment is difficult, but doing it will ensure it fits flush against the heads.
- Rumble goes away but it still sounds good. I'm using the Invidia Q300 mufflers, no drone with this setup, sounds smooth and a little throaty at low loads and opens up with high load.
Bought these to replace my 2011 WRX's poor quality UEL headers from previous owner. Fitment was perfect, and they ship you plenty of titan wrap to keep them covered. Build quality is amazing, and I hate that I had to wrap it and now show it off.