2013 coupe turbo same turbo as the old revisions?

[-LmG-]

I read online that the original Coupe turbo's had a TD04-13t installed which maxed out at 10psi.

Is the turbo on the 2013 revision the same or different?

 

[RealtorBob]

"Car and Driver" Magazine says it has the Mitsubishi TD04H turbo making 15.0 psi.

 

[mikec]

TD04H only tells part of the story... C-and-D left out the critical part!
Mitsu turbo names break down into three portions:
TD is the center "cartridge" portion; if Mitsu is still using "TD" then I wonder if the coupe turbo cartridge design is a descendant of the ones used on later Starions/Conquests and the Eclipse/Laser/Talon series cars.

The numbers after TD specify the size/type of turbine (exhaust side) wheel; this is what draws energy from the exhaust to spin the turbo. An 04 wheel is kinda small; it'll spin-up at low RPMs (reduces turbo lag) but may end up being a flow restriction (too small) at high RPMs & wide open throttle. Folks that like to crank up the boost will only magnify this tradeoff.

Then comes the most important part - and what C-and-D left off: the "-##" portion. The numbers after the dash describe the compressor wheel - the part of the turbo that actually generates the boost pressure. Usually it is a 2-digit number plus a letter: the numbers specify the general size again while the letter selects between various blade shapes/trims at that size. A "13" wheel size "fits" a smaller displacement engine - again helping make boost pressure at low to mid RPMs with minimal lag. It may not be able to flow enough air (enough "CFMs") to keep up with the engine's air appetite at wide-open-throttle & high RPMs though, choking off the high-RPM power a bit. The "t" letter? Don't know that one... "t" wasn't one of the letters in use back in my Starion days. "B", "G", and "A" are the letters I remember.

The real question is the turbo "map" which is a cross-plot/carpet-plot of the turbo efficiency & performance at various air flow rates and output pressures.

On the older Mitsu turbos, the compressor wheel bolts onto the shaft that is physically part of the turbine wheel... probably the same today. Swapping the compressor wheel was a common mod to Starions/Conquests to either get more boost pressure or to move the RPM range around to match other mods done to the engine. Of course the aluminum housing (the snail-shaped piece) of the turbo has to be machined internally to fit around a larger compressor wheel. Back in the turbo 80s there were many shops that rebuilt turbos and could do wheel swaps & housing machining upgrades for a reasonable fee. Such shops may be making a comeback now with the recent resurgence of turbocharged engines. Lots of fly-by-night turbo shops out there too... buyer beware!

mike c.