The Truth Behind The Subaru EJ-Series Engines -

[kjaglal76v2]

oh & and import tuner magazine article IS NOT a technical contribution, esp one filled wid contradictions

[Aaron 2NR]

Conclusion
13 2008 Subaru Impreza WRX STI Engine Bay
What began as a baseline dyno run of 259 hp and 279 lb-ft of torque was quickly revamped with our final run of 288 hp and 354 lb-ft of torque, a gain of 29 hp and 75 lb-ft of torque. These were impressive power gains that were made possible with the proper selection of parts and tuning. We can't stress enough how important tuning is when looking to create horsepower as our STI is living proof that Subaru's have definite power potential.

Read more: http://www.importtuner.com/powerpages/1 ... z31UVmkfw3

nice read for those who are willing to do some upgrades, now its the ej25 engine but its a nice yardstick showing power upgrades and tuning along the way...

[RIPEBREDFRUIT]

ej257 is not as strong as the ej207, but does offer much more Torque that the 2.0

[dread_2002]

any of allya spraying nitrous?
i never tried on my sti but always wondered.

use to spray alot of nitrous on my previous car, it was a stock sr20ve and it took 100 shot easy.
still have the kit home so was studying to put it on the sti.

anyone spraying on a bone stock subaru?
or even if yr car is upgraded what is the max shot u running?

[Aaron 2NR]

I kmow ren is on juice but he has a built motor...leo was on juice too (white penut with sti across the side)

[belalegosi]

any of allya spraying nitrous?
i never tried on my sti but always wondered.

use to spray alot of nitrous on my previous car, it was a stock sr20ve and it took 100 shot easy.
still have the kit home so was studying to put it on the sti.

anyone spraying on a bone stock subaru?
or even if yr car is upgraded what is the max shot u running?

Considering the piston ring problem (257), I won't try to big of a shot. Especially without a tune to compensate.
I consider the rings fragile...

ej257 is not as strong as the ej207, but does offer much more Torque that the 2.0

*cue* no replacement for displacement

[Aaron 2NR]

http://www.mrtperformance.com.au/perfor ... ance-guide

[Aaron 2NR]

[shogun]

Nice thread.

Sorry i only had time to read to page: 1

Keep the info coming guys.

[SUPERMAN2]

ecutek locks the ecu so u dont go farting around with the tune..
everyone always quick to blame the tuner when engine blow etc..
and everyone quick to say they know how to tune

i have a ecutek ecu and the car runs great.. hp like wow..reliable etc.
no complaints

if u upgrade parts go and get another tune

my car have a ecutek tune after the rebuild i was surprised the car started up one time idles smooth no complains the engine is still in the break in period
i spoke to jason and he seems cool i told him what i wanted from the car and he gave me some valuable advice on what i need to do and what stuff he taught i should get before i bring it for a retune

so far i have no complains with ecutek

[Lance]

If you didn't change any parts that would mess with maf scaling etc then it should have started up smoothly regardless of the map.

ECUTEK is a viable option though. A lot of guys put out big power with Jason tuning.

[Aaron 2NR]

found this link

http://www.dynocomp.com/details.php?bro ... 98&type=10

[Lance]

That's a considerable amount to pay for an incremental improvement in spool.

Is the company related to APS? It seems like a copy of the APS kit:

http://www.airpowersystems.com/wrx/aps_ ... /turbo.htm

I don't think APS makes it anymore though.

[kjaglal76v2]

this the same one that did 9.77?

[SUPERMAN2]

I dont think it made that

[kjaglal76v2]

yes, its the same car

https://instagram.com/p/1qz2cfvlI3/

[nervewrecker]

Posting so I can find this thread easy

[Aaron 2NR]

same car

[16 cycles]

Treadstone hot parts rotated kit
Treadstone fmic
Killerb Header
Forced Performance HTA3582
Id2000s
Walbro 485 rewired
P&L/CompClutch twin disk
Cobb AP
P&L Brakes
Stock 17" STI wheels with M&H drag radials

axles popping...

http://forums.nasioc.com/forums/showthr ... 069&page=2

[Aaron 2NR]

Really impressive I'm not that brave

[kjaglal76v2]

impossible locally anyways

[Glitch]

I wouldn't say impossible...but finding someone willing to spend the money to do it.

[GTR Fever]

Alot of people also talk about a tune is so important for a stock engine and whatnot. If you buy a car from the factory, it is designed to work as-is, without any sort of aftermarket tune. The stock ECU and map also allows for small upgrades (talking 02-07 WRX/ STi here) like a catback for example. The issue arises when people believe what they hear from their 'partners' about "take out them catalyst boy, it restrictin yuh turbo" or "them cars need a 3" downpipe to work properly"...or even the more popular "a cold air intake does give you rel extra power because of the colder air coming in"

When you do work like this, please people, it affects the scaling of the OEM sensors and ECU and REQUIRES a tune to correct for them. I have heard numerous horror stories of people locally changing downpipe and melting pistons.

If you leave it stock, run normal pump gas on a stock tune, you will be safe. I can safely say this as I have own numerous turbocharged Subaru's with stock everything (other than maybe a catback) and yet to cause major damage.

[Lance]

Alot of people also talk about a tune is so important for a stock engine and whatnot. If you buy a car from the factory, it is designed to work as-is, without any sort of aftermarket tune.

This analysis is a bit flawed. Especially if you consider an STi Spec JDM Subaru.

No car from the factory is mapped with Trinidad as the final consumption market. This includes any consideration for fuel quality. We simply do not have 97RON here and this is what is STi recommended given the boost levels and timing.

Knock sensors ensure that nothing is damaged but will the car perform as it was meant to off the factory floor? No it will not. No damage doesn't mean optimal performance.

[GTR Fever]

But the ecu is able to learn and will make corrections accordingly to accommodate.

[16 cycles]

I have heard numerous horror stories of people locally changing downpipe and melting pistons.

what's the physics that governs this cause and effect?

asking to understand....

[Lance]

It usualy makes corrections by either (1) cutting timing in individual RPM/Load cells (by FLKC or FBKC) or across the board (IAM reduction). (2) If the IAM drops low enough it will throw the vehicle in safe mode and activate wastegate boost.

The 02 senor is narrow band and it would add/cut fuel in open loop situations (idle, cruising etc.) This can help in these instances- doesnt really matter though, they are low risk anyhow. However, when you normally go into WOT or Boost situations the ECU switches to Close Loop and refers to lookup tables for targets, no adjustments are made. This is where the factory tune cannot help you maintain power through corrections. The only correction it will make is using feedback from the knock sensor (i.e. corrections 1 and 2)

In any event, all these ECU "learning and corrections" here will result in performance reduction.

[Lance]

I have heard numerous horror stories of people locally changing downpipe and melting pistons.

what's the physics that governs this cause and effect?

asking to understand....

Changing your downpipe to 3'' normally causes your boost levels to behave erratic (usually spikes). I've seen them spike upwards of 25psi after install and taper down slowly.

This amount of air in excess of the stock tune leans out your a/f ratios to insane levels. The incremental build up of heat that ensues probably causes the rest.

[crazybalhead]

Waaay no downpipe and intake without tune? did not know that.

[Aaron 2NR]

^ yeh subaru are special lol...i changed turbo inlet and had to retune because it started leaning