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-   -   Better, Faster (somewhat), Stronger! (

ecoflame 01-02-2013 02:08 PM

Better, Faster (somewhat), Stronger!
In October I spun a rod bearing, cylinder 1 I believe. After much deliberation and forum browsing I have decided on my course of action;

1. I am keeping her N/A. She's going to be my DD.
2. I want to rebuild the motor I have.
3. I want to build it better than stock.
4. I want to keep all "upgrades" within the stock ECU parameters.

I have done some basic research bouncing around forums, and this is where I'm at parts wise. Of course this is speculative, and I welcome additional information or opinions. BUT PLEASE KEEP IN MIND MY 4 OBJECTIVES ABOVE.

STI oil pump or after market oil pump (I forget the name, I have it written down somewhere). Anything bigger then 7mm.
Port the oil pick up lines for smoother flow.
Eagle piston rods (they'll be needed down the road)
Pistons I'm not sure on, hoping for insight from yall.
'04-'06 EJ257/255 head gasket -p/n 11044AA642 Port and polish heads, intake and header to match.
Delta cams - stage 2 regrinds?
Valve train leave alone?
New valves and stem seals
'05 RS engine mounts, GrPN trans mount, urethane filled differential mounts. This will ease the bucking when letting off the throttle? Yes?
Hypersingle clutch with spring hub and lighter flywheel
Oh and light weight pulleys.

I welcome all opinions and advice, so what do yall think?

ripemeat 01-02-2013 02:16 PM



who's/how are you going to tune it once you do all these mods?

it's been tried and tested to the point of diarrhea & vomiting on NASIOC and 2.5RS. building n/a subaru motors comes out to be widely not worth the cost for what you gain from it. that is why so many GC8 guys do bolt-on turbo kits at like 3psi, and why 3rd gen legacy guys do sti swaps.

FJuan 01-02-2013 02:27 PM

^^ Exactly

Without upgrading your ECU to recalculate for the additional air/fuel, the motor is going to run rougher than you think.

ecoflame 01-02-2013 02:54 PM

Why - because I don't have +8k for a STI swap. I'd like to maintain a DD aspect. And I don't feel like spending one too two months merging the two harnesses. Most of what I have compiled came from a guy on RS25 who did a N/A build and made some decent power at the wheels. Now I far from expect the output he made, he did some serious and respectable work on his ride. I just want this motor to be the best it can be.
Also I'm not a huge fan of boosting vehicles that didn't come with a stock turbo. Personal preference.

I'm trying do to as much as I can with out tuning. From what I've come to understand my ECU isn't tuneable and piggy backs just cause problems.

ecoflame 01-02-2013 02:56 PM

Also aren't the cams the only mod that would require tuning?

ripemeat 01-02-2013 04:06 PM

cams, pnp head, and pistons(which would mean your CR would probably change a little) are all issues that need to be tuned for. plus, how do you think the engine is going to make power for these mods? the engine isn't magically going to be faster with physical upgrades, you need a tune in order to allow for the performance to happen. it's just not a good thing to dump money into. you'd be better off just finding a suitable replacement and DD'ing it.

ecoflame 01-02-2013 04:41 PM

Cams and Pistons I can agree with, PnP eh I dunno about that. I'm not trying to start an argument, but how can you say the engine wouldn't be faster with physical changes??? Different cams means a longer or shorter duration of the valves opening, direct effect to performance. A change in CR, direct effect to performance. Granted you do need to tune to maximize the changes made, but to say simply changing the parts won't benefit the performance is naive. Having said that I thank you for your input. :D

compsurge 01-02-2013 05:11 PM

What you want is a completely stock engine.


I'm not bashing you. I'm being completely serious.

If anything, get groupN motor and transmission mounts, but skip the pitch stop, as it's not any different with the groupN.

Don't get a lightweight flywheel or a crazy clutch setup on a car that doesn't need it. You will hate yourself every time you have to change gear in your daily drive.

You can't build that engine better than Subaru did, especially since you aren't going to run a standalone/tune.

lingling1337 01-02-2013 05:13 PM

Not gonna weigh in one way or the other but I would love to see this build thread

ecoflame 01-02-2013 05:47 PM

Was there a lol or Haha following the statement?

Post #75

ecoflame 01-02-2013 05:48 PM

Lingling about 3/4 of what I want to do came from the above thread. Happy reading! Lol.

bomberlegacy 01-02-2013 06:06 PM

I saw a show one time, they took an Impreza and put a high flow intake and exhaust on it and lost horsepower. Then had it tuned and it was well over the stock level.
Point being, our ECUs are picky and any little change in airflow needs to ecu work.

tuning all of that plus higher octane would be good plus removing the drive by wire delay is nice.
What are your plans for it in the future? All the mods you have mentioned even with a tune won't help the n/a all that much. You need forced induction.

ecoflame 01-04-2013 07:10 PM

Future plans are just keep it DD. Now if something horrible happens to the motor (knock on wood) that's opens up new options. EZ30 more then likely. I'm just trying to give her more pep in her step. Without shoving air down her throat.

bomberlegacy 01-04-2013 07:55 PM

Only my opinion, but if it is just going to be a daily driver, rebuild it without spending extra on beefy rods and pistons. Delta cams would be nice and cheap. I am not sure if the OEM valvetrain will be sufficient. Then tune it for the best gas you have in your area. The tune will make the biggest difference, performance will be worse if you don't.

Brprs 01-04-2013 09:33 PM

H6 swap. Done. The whole n/a 4 cylinder high comp bs has been beaten to death. Yes its cool to say you have a decent amount of power naturally, but you'll be out of money very fast. Being able to drive it every day comfortably is most important in a daily driver. Best to leave it as is.

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