gday, ive found a to4 turbo with a 42 mm external wastegate for a really good price. i was wondering what sort of an upgrade the would be for my s4 turbo, and what supporting mods i would need, thanks.

 

I hope you didn't find them on ebay. Which To4 turbo?

Chances you are going to need a to4 manifold, feed and return lines for the oil( water too if its a wet chra), a custom downpipe, fuel mods, ecu, clutch and other drivetrain/suspension mods depending on what power levels you plan on running.

 

to get running safely... all you really need is manifold, that has an elbo for external wastegate, downpipe, piggyback, injectors, fuel pump. the rest depends on how much boost you want to run. over 10psi, i guess the stock TMIC is useless, so youd need fmic, throttle body elbow, and misc piping.

 

i can make manifold and down pipe and intercooler pipeing, i just dont have a great knowledge of turbo modles and whatnot. its a stock engine at the moment but will most likely become an extend port or bridgeport when it needs a rebuild. would this turbo have enough flow for a big port? at the moment i have made a full 2.5 exhaust off the back of the turbo. the back of the exhaust houseing is milled out so the 2.5 inch pipe gos right up to the exhause wheel, im running a tdo5? wastegate flap and big wastegate port and i made a flange so i can run a straight screemer pipe off that, would i be better off just upgradeing the compresser wheel and houseing? its just that the to4 and garett wastegate is 400 nz which is like 200 american,

 

It's not recommended to still be running the stock ECU.


-Ted