The Truth Behind The Subaru EJ-Series Engines -

[Aaron 2NR]

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

i am not taking your chain up ryan....we already broke the stock powertrain record lol

[R. Mutt]

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.

With the exception of having open and closed loop backward - this is legit talk. Closed loop utilizes the narrow band o2 sensor input in an attempt to maintain stoich during low load driving while open loop refers to look up tables for boost, timing and fuel during higher load situations

[kjaglal76v2]

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

i am not taking your chain up ryan....we already broke the stock powertrain record lol

local record?!?!

[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.

With the exception of having open and closed loop backward - this is legit talk. Closed loop utilizes the narrow band o2 sensor input in an attempt to maintain stoich during low load driving while open loop refers to look up tables for boost, timing and fuel during higher load situations

Man I always mix them up. Thanks

[Aaron 2NR]

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

i am not taking your chain up ryan....we already broke the stock powertrain record lol

local record?!?!

12.2@110mph




based on information we pulled from Autosport, local tuners and mechs, the fastest recorded was 12.5 @ wallerfield. Last year we ran 12.48 & 12.42s. In January we did 12.42 again.
In Feb we did a retune on the car after we changed the inlet to the turbo so decided to run the car at camden last weekend. On Saturday we ran 12.38s. On Sunday we decided to play with tire pressures and ran 12.35, 12.31s and then 12.29s.

All runs were done on pump gas. Only mods done to my engine/ powertrain is tomei downpipe, greedy exhaust, perrin turbo inlet and cai intake with meth injection. other components are factory stock (injectors, coils, etc)

The car is tuned by Ryan (Glitch on the forum)




Based on information we pulled from online, the fastest in d GD chassis with a VF37 turbo can be seen below. the other two are in GC chassis which is a lot lighter and E85 fuel. Still waiting confirmation from another Subaru forum.

[Ted_v2]

Congrats, Thats quite good on a stock turbo.

U have interior in ur car?

[Aaron 2NR]

Full interior. A 5 gallon meth tank in the truck on the left and a 1 gallon backup on the right. Car had 1/2 tank of fuel

Ran on toyo r888s


Without me in the car it weigh 3266lbs

[Glitch]

I really do think this is a world record for that chassis, stock turbo on pump and meth

[R!CH!E]

Congrats in order! 12.2 stock

[Aaron 2NR]

full interior

[eliteauto]

well done, congrats

[Aaron 2NR]

Was a good weekend at Camden seeing how the Subaru camp came out and represented!

Ryan showed what super n meth can do

Ren touched 11s

[Aaron 2NR]

check the attached link

http://mindovermotor.com/2014/06/18/sub ... ion-guide/

Conclusion

Subaru WRX STis are very solid cars up until a certian point (~350whp). Their sweet spot is right around ~300awhp, where performance is quite thrilling, but reliability is still preserved. It is also pretty cheap and easy to get an STi to the 300awhp level, so it’s accessible for most owners. Doing the basic modifications brings out the Subaru’s full raw character, and is really worthwhile for any owner to do.

More can definitely be gotten from an STi, if you have the wallet, the skills, and the patience to deal with the issues that come up at higher horsepower levels. However, for most people, there are far more cost-effective options out there if a 400whp+ is desired.

So when it comes to modifications, a Subaru STi is a great value until it’s not, and there isn’t much too much middle ground in between.

[Ted_v2]

Lemme ask you all this. What bottom end would you all prefer?
A rebuilt ej20 with forged pistons. Rods ect or a stock ej257 sti block with the same 2.0 heads?

[Aaron 2NR]

i believe this vid shut up a lot of the naysayers

[kjaglal76v2]

nice car, nice vid, nice time, good to see scoobies finally catchin up

[Lance]

Subarus were always ready for the challenge. This setup is 8 years old.

It's tuners that are catching up.

[Aaron 2NR]

^not really....it have mechs in trinidad who rebuilding engines and on initial startup all you're hearing is piston slap...then when the engine break, they blame the tuner, the owner, say oil cause it....

then there are a lot who say you cannot make power over 300 unless you forge for safety...i even heard a "tuner" say he cannot go over 300 unless you get 1000cc injectors......and these are people who play they know everything about subaru locally

[Lance]

I was referring to kjaglal76v2 comment about Subaru's catching up. In this particular case, it's a stock motor so most of the issues related to "mechs" or "rebuilding" are irrelevant. This is a tuner dependent scenario.

I'll also touch on your other comments as they are also somewhat erroneous

Minimal slap on STARTUP on a rebuilt motor with forged pistons is totally normal. Actually If there isn't a slight amount of slap on STARTUP then I would be worried.

The reason is simple, forged pistons are not cast OEM pistons and they will expand more with heat. If the piston to bore clearance doesn't account for this then the clearance will be too tight after expansion.

In any event, this is not squarely the mechanic's fault as there are a lot of other players involved. Machine shops locally do not rebore with torque plates so cone-ing is expected post heads assembly. At the end of the day, if i'm a tuner and I hear excessive piston slap on a warm engine then I will refrain from tuning. Can't they tell the difference? This is not to nullify mechanic fault but there is a certain chain of responsibility that should help mitigate this problem.

Going over 300 (320+) on stock 550cc injectors without methanol injection is pushing the IDCs to the limit, no tuner will dispute this. Any that say the IDCs are safe is probably running a lot more timing than they should. 1000cc is overkill but telling a customer that pinks are OK is playing dice with your motor.

[Aaron 2NR]

i'm not talking about the normal little thick noise on startup...im talking about a literal slap noise...mech revving the engine less than 30secs after its started. I would love to post the vid but not in the mood for all the nancy drama.....


my comment come from the same tuner who said methanol injection is a waste of time...btw the said car had meth injection and he said "methanol makes a subaru hard to tune, throw in some 1000cc instead and we going over 300hp"




i will stick to my point that a lot of the issues locally with subaru and why you often hear, subaru is crap and the engine cannot make power is simply mechanical errors, incompetent mechanics and tuners who dont know quack.....

[Aaron 2NR]

there was even the case of a local spec c that just got rebuilt, a foreign tuner told the owner and mech he's hearing a lot of piston slap, its sounding like something is loose inside the engine. The mech said go ahead and tune, we deactivate the avcs....3 pulls later they had to be pushed off the dyno....

i'm talking about a very respected tuner.....

[Aaron 2NR]

at the end of the day, we are seeing locally, tuners who are able to tune subaru safety and make good power on stock internals....so i say kudos to them..

i personally not that brave to attempt that kind of power on stock internals like what cj did....

[Lance]

My intention is not to see this thread turn into mass hearsay. Most of what I've read from you thus far is simply accounts of your interactions with "mechanics" and "tuners". After reading it the only thing that is left to say is - cool story bro. Zero technical input that can contribute towards consensus (i.e. the truth).

Lets keep the thread to technical content that can be discussed and debated. The thread is to benefit all, not peddle a personal position.

[GTR Fever]

Is it only Subaru engines that have piston slap on startup with forged pistons? Reason being I personally own and have close friends who own cars with forged internals with ZERO piston slap. Whether cold or hot, same thing.

The ticking noise is understood, piston slap...not so much. That is one of the main reasons I am afraid to have engines built locally. The answer "it go work jus so" or "thats how we accustomed doing it" are not suitable responses in my opinion. Because when something goes wrong it becomes a blame game.

There are several STi's out there with around 300hp on fully stock setups without meth. A lot of them are daily driven as well. At the end of the day, once your car is maintained right, and your tuner (whoever it is, no names being called) is capable enough, a Subaru engine can make good power on stock internals.

[Aaron 2NR]

nice car, nice vid, nice time, good to see scoobies finally catchin up

incase you wanted some more info on the car....

quality parts, a good tune and proper maintenance and wonders can happen

http://forums.nasioc.com/forums/showthr ... 069&page=4





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

[16 cycles]

props to anyone hearing piston slap over a single scroll full 3in exhaust ej20....

edit:after posting the above, i was made aware of how bad piston slap could be.....wha the morocoy...!!


thanks to the tuner for educating me !!

[JJ16]

Okay that went from 0 to 100 real quick

But the fact still remains, if you have a mechanic that does not build the engine properly, its NOT going to last.

Point is, in Trinidad (atleast) many of these "Subaru" mechanics, aka "TOP" mechanics have no clue on the correct procedures of rebuilding a subaru engine. I am not a mechanic so it is NOT my field to say "yea i could build engine better than that man" but it does not disqualify me from commenting on the fact that they doing rubbish. Its not hearsay I"VE SEEN first hand some of these mechanics make SILLY mistakes...

Apart from the common problem of some mechanics having customers that maintain 100% faith in them, regardless of how many times their engine breaks they gonna keep coming back...Kudos to them...But with that being said you've clearly *from what I gathered* said that

"In any event, this is not squarely the mechanic's fault as there are a lot of other players involved. Machine shops locally do not rebore with torque plates so cone-ing is expected post heads assembly."

As far as I am concerned as a customer, if YOU are my mechanic and YOU carry my engine by a machine shop that does a POOR job, thats YOUR fault... a mechanic isnt a friend that is just assisting me with "doing ah wuk"...

I respect your opinion, even if you dont respect mine... thaz life...

but if I spend $40,000 on a build and the mechanic says THIS WILL get you 600WHP...I would be aiming for somewhere NEAR that..don't tell me that by 340whp i hearing Laventille rhythm section in my engine and its going to be blamed on the tuner... once again not hearsay.. i've seen this happen.

[Lance]

You've completely missed the point of what I've said. In the process of paraphrasing and quoting my comments you failed to acknowledge this line:

"This is not to nullify mechanic fault but there is a certain chain of responsibility that should help mitigate this problem".

My example was simply aimed at setting up an discussion to illustrate that there are many actors when it comes to setting up a car for power. The owner is the nexus and the tuner and mechanic are two of the nodes. Electronic and Mechanical manipulation are two sides of the same coin.

I guess I have a different threshold when it comes to responsibility but if i'm a tuner and I know without reasonable doubt that this car is knocking then I unplug my tactrix and go home. Despite what the mechanic or owner is saying. Or is it that tuners must also have 100% faith in mechanics?

When an engine fails on the dyno do YOU review the logs and roms edits to establish causality?

Regarding my example of machine shops. Just as customers have preferred mechanics and tuners they also have preferred machine shops. These decisions are not always dictated by the mechanic (just as the decision of tuner). Some vehicle owners prefer to have a certain shop do their machining and others the same.

[JJ16]

Lance I did not fail to acknowledge anything I was quoting a specific line, which is what I did...

If you read what I said in its entirety you would then notice that my example EXCLUDED the customers involvement.

Yes there are many variables in setting up an engine, but it begins with the mechanic...and thats the point in which I WAS making. Everyone is different, but I do not blame a tuner when a tuner is not at fault. If my engine is poorly built then it would be the mechanics fault.. If I bought bootleg parts and the engine breaks, thats my fault...

Only part of my statement was addressed to what you said... if your opinion is I missed the point, well so be it. I read what you said, and I disagreed to some extent, plain and simple.

[16 cycles]

the thread is about stock engines' strength or forged engine build/tune?

the points you all bringing out on forged engine/build/tune exist with all platforms...