LimitlessEvo7

Hey guys I just got my evo 7 tuned on 93 octane and the tuner said its struggling to break past 300wkw on 93 octane. Here's the mods list:
2001 Evo 7 GSR
Stroker 100mm Manley forged crank
CP 85.5mm forged pistons
Manley H beam rods
Kelford 272 camshafts
BC springs and titanium retainers
Tomei adjustable cam gears
Port and polished head with stock sized valves
XS power exhaust manifold
FIC 1850cc Injectors
Walbro 450 Fuel pump and aftermarket fuel rail, fuel pressure regulator
Spoolinup C.O.P kit
GSC full race balance shaft
3 inch UICP, aftermarket larger intercooler 100mm thick and LICP
Link G4 Ecu running 4 bar MAP sensor
STM intake pipe and pod filter
Aftermarket down pipe and straight 3 inch exhaust with test pipe
Ported Kinugawa TD06sl2r-25G turbo with antisurge compressor housing

I've just gotten it dyno'd on a dynapack and here are the results on 93 octane at 23psi tapering to 18:




The tuner says that the TD06-25G turbine is too small and is causing a lot of back pressure so there's no real increase in power from raising the boost up? I'm just wondering if anyone has had this problem with a 25G before at these power levels. The tuner recommends that I upgrade to a bigger turbo and I thought that maybe the MAP EF4 would be sufficient as a high flowing stock frame turbo. The tuner however suggested going with a Borg Warner 8374 full T4 turbo kit instead and he's not sure if the EF4 is up to the task of achieving my goal of 400kw+ at the wheels on E85. I've seen dyno sheets on here showing the EF4 achieving those numbers but I'm unsure now if my tuner will able to get the most out of it since here in New Zealand the MAP turbos are quite rare.
What would you guys suggest I should do to reach my goal, should I go with the stock frame EF4, or the full T4 twin scroll kit with the 8374? Any help will be great as the car is due to be in a local event by January next year and I need to make up my mind as soon as possible.

CT9A PR

time to change tuner your tuner sucks....

These 25G dont like low octane might want to add meth.....

Also might want a stiffer waste gate actuator so it holds more boost up top

These turbo will also suck at anything under 26-28 PSI they live above 25 PSI.....

Contact tcompusa or puredriveperformance

LimitlessEvo7

Tuner keeps saying that the exhaust turbine is too small etc and is causing too much back pressure and not showing any gains in power over 18psi. I've seen this turbo do 570+whp on E85 so I'm a bit skeptical on the tuner's opinion.

CT9A PR

Change tuner he sucks.

Use more preload and better fuel.

Contact an etuner n Evom.

My choices would be tcompusa or puredriveperformance.

Its cheaper to change tuner than your complete set up.

zentac

The turbo manufacture recons they are good for around 386kw which is 493 bhp but that will be at the engine not the wheel, you managed 298kw which is about 399bhp at the wheels + 20% transmission loss would be around 478 bhp engine which is not far off it being flat out.

I would try an larger actuator spring (or more pre-load if its internally gated) but you are going to struggle making the 400kw wheel (536 bhp wheel) that you want.