2015 STi - Page 12 - Perth-WRX.com

Soksta · #**111** 18-06-2014, 05:13 PM

Might be interesting reading for a few on here...
2015 WRX and STI suspension TECH thread.

Darken · #**112** 19-06-2014, 09:59 AM

Nice, looking forward to the pics!

Quote:

Originally Posted by maccar86

I just placed my order and deposit down for the 2015 STI premium. I went with the dark grey. I recon they look hot. Delivery is 6 weeks so i'll post up some pics when I pick it up

thehowlfactor · #**113** 19-06-2014, 10:07 AM

Spotted a red one with aftermarket rims yesterday. I still don't like it. It reminds me for some reason of a car that people hot up to look like a sports car. I know it is, but it just doesn't look like it.

Tony · #**114** 19-06-2014, 10:57 AM

I would have waited for an FA engine sti myself. But will still he a sweet ride dude. Am jelly.

spider · #**115** 19-06-2014, 03:42 PM

Quote:

Originally Posted by Tony

I would have waited for an FA engine sti myself. But will still he a sweet ride dude. Am jelly.

Hey Tony

I'm pretty keen on getting the 2015 STi myself but after buying the first version of the 2009 wrx (and then kicking myself after the second version came out with the wide body) I'm gonna make sure I make the right decision this time round. Can you tell me why you would wait for an FA engine sti? I don't even know what FA is!!!

Sorry if this has been posted already but I have been away from this forum for over 3 years now and have not been reading anything much about the new wrx's or sti's until I saw the massive $10k price drop recently and this has got me all interested in owning a Subaru again.

Thanks mate

joshrx · #**116** 19-06-2014, 06:25 PM

Quote:

Originally Posted by spider

Hey Tony

I'm pretty keen on getting the 2015 STi myself but after buying the first version of the 2009 wrx (and then kicking myself after the second version came out with the wide body) I'm gonna make sure I make the right decision this time round. Can you tell me why you would wait for an FA engine sti? I don't even know what FA is!!!

Sorry if this has been posted already but I have been away from this forum for over 3 years now and have not been reading anything much about the new wrx's or sti's until I saw the massive $10k price drop recently and this has got me all interested in owning a Subaru again.

Thanks mate

FA is the newer engine code, just like EJ is the "current".

Apparently the new engines are good for tuning but just not deployed yet for the sti, but expected to be soon.

using the Perth-WRX mobile app

phizzle · #**117** 19-06-2014, 08:03 PM

The new FA engine in the WRX is a turbo version of what they have been running in the the Toyota 86/Subaru BRZ love child. One of the biggest changes is direct injection which helps create a better cylinder burn, hence making more power while being more efficient. It is a totally redesigned engine which carries on the EJ boxer tradition. MRT cracked the new ECU and made some very impressive gains on a tune only on an MY15 WRX. Bear in mind the dyno readout below is with an allegedly 100% stock car with the exception of a custom tune. No big exhaust and running +2psi over stock boost.

Blatantly pinched from another thread on P-WRX

Soksta · #**118** 19-06-2014, 08:34 PM

Would be interesting to see if the following is true.

2014 WRX (MY15 WRX) - Part 2

Quote:

Ok learned a fair bit last night about the new WRX.

While both the BRZ and WRX run direct injection, the WRX's is completely different and vastly superior. The WRX engine is not just a BRZ engine with a turbo slapped on, its a significant redesign.

The BRZ's FA engine runs both standard traditional injectors and direct injectors. So it runs two injectors per chamber. This is primarily because its direct injection technology is not as mature as the WRX's. It needs the standard injectors for cooling, to combat carbon build up, and also because its direct injection and ECU are not capable of running on their own.

The new WRX however features exclusively direct injection. It injects the fuel at roughly 3000 PSI and atomises the fuel. To put it into perspective the standard Subaru STi 650cc injectors run at around 80PSI, up to 90PSI when tuned. We weren't told how Subaru have overcome carbon build up problems and cooling with the new FA20T, but none the less this is a true Direct Injection vehicle and far more then a BRZ engine with a turbo slapped on!

The new WRX from the factory runs a compression ratio of a crazy low 10.6 and from peak boost of 19 PSI. This is absolutely amazing especially when you factor in this is a factory tune for 95RON Fuel! For the old EJ257s running 19 PSI of boost was danger zone, this new WRX is running a level of boost that the STis couldn't even handle safely.

On 98RON and with nothing more then a tune the new WRX will gain an extra 40kwatw. It will go from roughly 165kwatw to 220kwatw. This is with NO mechanical changes, not even exhaust or intake. In comparison the new MY15 STi with the older EJ257 engine, achieves around 220kwatw on E85. So the new WRX on 98RON fuel, alower octane grade, can match an ethanol powered STi!

Subaru have also had to change ECU vendors and have moved to Hitachi. The new ECUs utilize completely different programming language then the previous BRZ, WRX, and STi ECUs which have largely for the past decade been from the same manufacturer. I forget their name but they start with a D. The reason for this change was the timing and complexities of Direct Injection required a significantly faster and more complex ECU then what Subaru have ever used. Downside of this is previous Subaru tuning software and open source stuff will NOT work on the new MY15 WRX.

It is believed in the next few years Subaru will be eliminating the throttle body completely from the WRX and the ECU and CAMs will take over. With native DI there's almost no reason to keep it.

Racerom, flat foot shiftting, bleep on down throttle, all these tuning features are still possible. Tuning the new ECUs is easy and already underway, but it will take some time to master the new DI technology.

It will be some time before aftermarket turbos and bigger injectors are available. The new turbos are completely different and unique size, so after market manufacturers will need to engineer exclusive turbos for the new WRX. Also with direct injectors being unique as well you wont be able to simply drop in aftermarket ones, they will need to be purpose designed for Subaru. I was told it will likely take a year or two before we start seeing aftermarket injectors, turbos, and mechanicals come available for the new WRX.

Seriously this engine is flapping amazing....

Edit: Post was aimed at the FA found in the new WRX, not the current EJ in the new STI.

spider · #**119** 20-06-2014, 08:13 AM

Thanks for the responses!! So the FA engine in the wrx sounds fantastic! Are they going to definitely put one into the sti at one stage or are you guys just being hopeful??

phizzle · #**120** 20-06-2014, 08:46 AM

Quote:

Originally Posted by spider

Thanks for the responses!! So the FA engine in the wrx sounds fantastic! Are they going to definitely put one into the sti at one stage or are you guys just being hopeful??

The new engine is the way forward.

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