2005 jdm wrx stock internals

Hey,

I have a few questions about my WRX before I start buying parts, and I’d really appreciate your opinion if you have the time.

I’m still in high school, so money is obviously pretty tight for someone my age, and I’m trying to make sure I spend my money wisely rather than buying parts twice or doing things that aren’t necessary.

I recently imported a 2005 Subaru WRX from Japan. It’s completely stock ej205. I’ve been speaking to someone in another state here in Australia about making more power while keeping the factory engine internals, and they recommended the following setup:

* VF34 turbo

* VA STI top-mount intercooler

* ID1050X injectors for E85, or STI blue injectors for pump fuel

* AEM 340 fuel pump

* High-flow downpipe

* tune

I wanted to get another opinion on this combination and whether you think it would be a sensible setup for a stock-internal EJ205. I’m particularly interested in making good, reliable power rather than chasing the biggest number possible.

As the car sits right now, it is completely stock apart from a GFB blow-off valve. I also have an HKS intake from Japan on the way, as well as a turbo inlet pipe.

I have quite a few more questions so out of the parts listed what can i install and then still be able to drive the car down to got it rex to get tuned and if needed install other parts because i want to learn to install some and also i dont wanna pay extra for installing of parts? and also would i need upgraded oil pickup or baffle system or an aos/catch can? and also if i don’t upgrade turbo until a little later can i still run all the parts you listed on stock turbo without it being overkill? so that then once i upgrade turbo it will be all set up.also are my stock injectors top feed or side feed? also are tgv deletes worth it. and with the fuel pump and injectors you have recommended do i need different fuel rails for the injectors and can i use stock fuel hanger or do i need a new one. and also is it worth buying aftermarket pitch stop mount? and i was wondering if it's important to buy a 3 port boost solenoid? and can my stock clutch handle 170-200kw atw? is there any other supporting mods you'd suggest? and would i be able to go front mount intercooler on stock turbo until i eventually upgrade turbo?

thank you so much hope to hear back soon

Hi Lucas, that combo of parts is a pretty sensible and well proven path. The two killers of any Subaru engine are knock and oil surge so if you can stay away from both then you'll be in pretty good shape. On this basis I'd highly recommend the E85 route if possible. It just gives you a much wider tuning window and all but eliminates any chance of knock occurring. If you plan on any track days or drag racing then I'd highly recommend a baffled sump to help eliminate oil surge/starvation.

You can install all those parts with the exception of the injectors and still drive it (carefully) on the stock tune. I'd just avoid using high load/full throttle until it is tuned. If you're tuning the stock ECU then you'll actually want to do the inlet upgrade and the injector upgrade separately anyway, otherwise it's impossible to properly calibrate the MAF sensor. You could run all the parts with the stock turbo but there will be little benefit unless you run E85 (which would require the fuel system upgrade).

A catch can isn't essential but I'd recommend one. It means the engine won't be ingesting blowby gasses which will include oil particles which can reduce the effective octane of your fuel. A JDM 05 WRX doesn't have TGV and they use top feed injectors. A 3 port boost control solenoid isn't essential but definitely preferable. Your stock clutch should handle 200 kw atw but this will depend on the current condition. If it's high mileage or had a hard life then you could find the limit.

thank you Andre. so i can install all these parts besides injectors and be able to then drive it to the tune shop? can i ask what parts you would recommend for a daily driver/weekender and i d'ont mind upgrading maybe small things in the engine like head studs i'm just trying to avoid a very expensive build if i don't need to spend a lot? also whats the safest max amount of power i can make before upgrading internals? the car is currently only at 46,000km with original everything (engine,transmission etc) and also is a frount mount intercooler a beter option without it being overkill?

The limiting factor of these engines is the internals so I wouldn't bother upgrading head studs. This would also be a big job since you can't do it with the engine in place. Personally I'd go to a FMIC as the stock top mount acts a bit like a chimney at low speed and results in higher IAT.

It's not possible to give a definitive power limit as it depends on so many aspects - The tune being a huge part of this. Generally I'd be happy running a healthy EJ205 to around 200 kw atw. You may get away with going a little further with some careful boost shaping and control of ignition timing to limit peak torque. The use of E85 provides a nice safety margin as knock almost certainly won't be an issue.

so do you think these parts are good:

tune,front mount intercooler,id1050x injectors,aem 340 fuel pump,invidia turbo back exhaust with high flow downpipe, catch can, intake, 3 port boost solenoid and this would most likely be on stock turbo for a while and then eventually upgrade to a vf34 turbo when i save up? and with all of this would i be able to keep stock clutch until i upgrade turbo and stock internals?