Which Subaru WRX STi is best?
Oct 20, 2015 at 11:34 PM Post #46 of 52
I wasn't responding to the OP. The relevant text and its author were quoted in the post.

Edit: I see what you were talking about now. Yes, the Canadians are subject to different constraints.


Yah its 15 years here in Canada. We already has 2000 Subaru wrx Sti Bug eyes being imported. Ive driven a few right hand drive cars, it's definitely unique but I wouldn't want it all the time. 
 
I do live in Northern Canada, so a turbo AWD car is pure bliss.
 
Dec 19, 2015 at 11:29 PM Post #47 of 52
 
Problem is the reliability. A lot of these Sti's need motor rebuilds because they are driven so hard. you know?

I'm not sure the reliability issues are simply from lack of mechanical empathy. Most of the subbie owners I know from autox and track days, so they're all driven hard, and are maintained well since they're owned by enthusiasts. Some of these just take a beating and keep on ticking. Others are plagued by trans and motor issues. The ringlands blowing is a real issue. But some just never experience it. My guess is, it's more a roll of the dice, likely it's an issue with quality control, or manufacturing differences.
 
Apr 10, 2017 at 6:43 PM Post #48 of 52
Hey, I realize its quite a few years later from the start of this thread, maybe there is a chance it't still active?
 
Anyways, I'm 17 and busting my chops to hopefully purchase a wrx sti hatch for my own 18th birthday next march. 
 
I am-as much as I hate to say it-in that fanboy/honeymoon phase where everything about the car sounds awesome.
 
I'm looking to gather insight into the risks of getting "married", would like to see what the housework is like beforehand.
 
I do have an affection for the "blob eye" sti's but am looking for a 2014ish hawk-eye model
 
I plan to use it as my daily, *think* i want to upgrade it, will get lots of use on the roads but not racing sort of stuff so no real heavy, stupid use. 
 
main question is: which engine of the sti hatchback's is the most reliable? and does anyone thing they will make the sti hatches again?
 
also, what's with the sgp chassis stuff? seems odd that they're using the same chassis layout for multiple models etc. 
 
that's all i have for now, thank you for your future response! 
 
-Schuyler
 
Apr 10, 2017 at 8:13 PM Post #49 of 52
  Hey, I realize its quite a few years later from the start of this thread, maybe there is a chance it't still active?
 
Anyways, I'm 17 and busting my chops to hopefully purchase a wrx sti hatch for my own 18th birthday next march. 
 
I am-as much as I hate to say it-in that fanboy/honeymoon phase where everything about the car sounds awesome.
 
I'm looking to gather insight into the risks of getting "married", would like to see what the housework is like beforehand.
 
I do have an affection for the "blob eye" sti's but am looking for a 2014ish hawk-eye model
 
I plan to use it as my daily, *think* i want to upgrade it, will get lots of use on the roads but not racing sort of stuff so no real heavy, stupid use. 
 
main question is: which engine of the sti hatchback's is the most reliable? and does anyone thing they will make the sti hatches again?
 
also, what's with the sgp chassis stuff? seems odd that they're using the same chassis layout for multiple models etc. 
 
that's all i have for now, thank you for your future response! 
 
-Schuyler

As I mentioned, the biggest issue with these EJ25 motors is ringland failure. There's simply no agreed upon accepted answer on why it happens. If by "upgrade" you mean you want to modify for performance. You'll increase the risk of having ringland failure. Cobb access port + a competent tuner can minimize the risks. But there are many other factors that could cause ringland failure. One is oil blow by, you'll need to install a quality oil catch can, and monitor it's levels, and empty as needed. Next is the fact the factory pistons aren't forged like the EVO, so if you go playing with increasing boost, they'll give sooner.
 
I highly recommend getting a compression test on any you're considering on buying. If any cylinder is too much lower than the others, move on. When you find one, I recommend not doing any engine modifications, not even intake/exhaust. Do all the recommended maintenance first. New brakes and tires if possible, and learn the car's limits. First performance mod should be a cobb AP. Don't use it to tune right away, use it to monitor, so you know what normal operating parameters are, so you can spot when something's wrong.
 
Also, the 1st gen bug eyes are known for weak transmissions. I have a friend with one who's on his 4th transmission, and can do the swap by himself on jack stands in 3 hours. No matter which generation you get, repeated awd launches are going to break a transmission sooner or later. I'd take care to avoid them, even though that seat sucking awd launch feeling can be addicting.
 
Apr 21, 2017 at 1:15 AM Post #50 of 52
  As I mentioned, the biggest issue with these EJ25 motors is ringland failure. There's simply no agreed upon accepted answer on why it happens. If by "upgrade" you mean you want to modify for performance. You'll increase the risk of having ringland failure. Cobb access port + a competent tuner can minimize the risks. But there are many other factors that could cause ringland failure. One is oil blow by, you'll need to install a quality oil catch can, and monitor it's levels, and empty as needed. Next is the fact the factory pistons aren't forged like the EVO, so if you go playing with increasing boost, they'll give sooner.
 
I highly recommend getting a compression test on any you're considering on buying. If any cylinder is too much lower than the others, move on. When you find one, I recommend not doing any engine modifications, not even intake/exhaust. Do all the recommended maintenance first. New brakes and tires if possible, and learn the car's limits. First performance mod should be a cobb AP. Don't use it to tune right away, use it to monitor, so you know what normal operating parameters are, so you can spot when something's wrong.
 
Also, the 1st gen bug eyes are known for weak transmissions. I have a friend with one who's on his 4th transmission, and can do the swap by himself on jack stands in 3 hours. No matter which generation you get, repeated awd launches are going to break a transmission sooner or later. I'd take care to avoid them, even though that seat sucking awd launch feeling can be addicting.

 
 
Thanks for the immediate response, I apologize it's taken me two weeks!  
 
I did some research on everything you mentioned, and only came up with the stuff you mentioned :D thanks for summarizing it so well! i did find a website that basically elaborated on your points-  https://www.maperformance.com/blogs/maperformance-blog/77034371-how-to-avoid-piston-failure-subaru-performance-tips
 
so the whole ringland failure thing is kinda caused by the alloy pistons, and the third ringland, but can be almost prevented by an oil catch and the ap. pretty neat stuff to me, those are definitely the types of upgrades id rather do to my car, ones that will help it last. so the ap can help fix the detonation timing, which is basically the whole lean vs rich gas/air combo, right? i never understood mapping/ how that was done, though it seems like the reflash thing on the ram could be solved by just adjusting the actual ecu and not having to technically bypass it with another ecu.. also the heavy load thing about the rpms, i guess thats what you were saying about no awd launches huh. cant believe the evo has forged pistons, you'd think subaru would have taken note of at least their own engine failure and fixed it over the last ten years or so? they've barely updated their engines it seems, or their interior.. 
 
so you say not to tune the access port, do you mean to stage 1,2 stuff or the base remapping too? ive read that the stock factory tune isnt all that great in the first place. with the reflash thing, so if your battery dies, you need to reset it? im probably not making sense, i just got off work. ill try and rewrite my questions another day when im thinking straight and comprehending the information better :)
thanks!
 
Apr 21, 2017 at 1:47 AM Post #51 of 52
ive been reading up on a FA20 engine with the avcs vvt, and the direct ports, sounds much better then the ej motors? though i guess it doesn't come in the impreza's. so this is the next evolution, is the vvt gimmicky?
 
Apr 21, 2017 at 4:44 PM Post #52 of 52
 
so the whole ringland failure thing is kinda caused by the alloy pistons, and the third ringland, but can be almost prevented by an oil catch and the ap. pretty neat stuff to me, those are definitely the types of upgrades id rather do to my car, ones that will help it last. so the ap can help fix the detonation timing, which is basically the whole lean vs rich gas/air combo, right? i never understood mapping/ how that was done, though it seems like the reflash thing on the ram could be solved by just adjusting the actual ecu and not having to technically bypass it with another ecu.. also the heavy load thing about the rpms, i guess thats what you were saying about no awd launches huh. cant believe the evo has forged pistons, you'd think subaru would have taken note of at least their own engine failure and fixed it over the last ten years or so? they've barely updated their engines it seems, or their interior.. 
 
so you say not to tune the access port, do you mean to stage 1,2 stuff or the base remapping too? ive read that the stock factory tune isnt all that great in the first place. with the reflash thing, so if your battery dies, you need to reset it? im probably not making sense, i just got off work. ill try and rewrite my questions another day when im thinking straight and comprehending the information better :)
thanks!

I'm not an expert with tuning, just know the basics. But basically an optimum complete burn of gasoline happens at a ratio of 14.7 units of air to 1 unit of gas.This is called "Stoich", lower than this is a rich condition, higher is a lean condition. The saying is "richer is safer and leaner is meaner", self explanatory. Turbo cars tend to need to run rich to avoid pre-detonation 10-11 is considered optimal. Be advised, running rich might prevent pre-detonation, but it also increase exhaust gas temps, and could kill a catalyst converter, as well as create heat issues after the exhaust system. The subaru ecu are modern, and well understood, which is why the cobb ap is even available. It'll flash fuel map changes, as well as pull monitoring data from the factory ecu. Fuel maps should only be modified by someone who has a firm grasp. Definitely don't attempt to modify the base map yourself without learning it thoroughly, and if paying someone, research them, and previous customers fully. But yes, I'm saying avoid the stage1/2 upgrade/tune packages until you really learn the car inside and out.
 
Biggest problem with these types of platforms IMO, are the vast aftermarket parts available, which tempts new owners to chase easy HP, and other performance enhancements soon as they get one. Then start street racing, doing highway pulls, and blowing up motors/transmissions, and/or wrecking. It's a terrible order to do things for a newbie. The proper order should be to get maintenance things done first, despite not having issues yet. Then upgrading the car from the ground up as you learn to handle it's limits. Starting with tires, brakes, suspension, then maybe power modifications. Learning a car's limits should start with low speed, high technical racing like autocross, then moving up to higher speed track days.
 
  ive been reading up on a FA20 engine with the avcs vvt, and the direct ports, sounds much better then the ej motors? though i guess it doesn't come in the impreza's. so this is the next evolution, is the vvt gimmicky?

vvt is basically what the popular "V-tec" is. I believe some subaru models, especially the turbo ones only have it on the exhaust cams, I'm not sure which though. It's not a gimmick. Direct port injection is exactly what it sounds like. Injects fuel directly into the combustion chamber, and not in the intake manifold. It definitely provides more potential for power and fuel economy. But it comes with issues of it's own. Primarily carbon buildup in the intake manifold (injecting fuel into the IM actually cleans it), which requires removing the IM and blasting the insides to clean the carbon buildup, not a simple or fun maintenance job. Another issue are the special fuel pumps required, which often aren't the best quality, especially when fuel demands are increased (more boost). DI requires fuel pressures well over 1000psi at stock boost, which is a big strain on the fuel pumps, and the fuel pump internals. I believe cobb offers upgraded DI fuel pumps and internals for a number of platforms. Lastly, DI doesn't have many options for increasing injector size for higher fuel needs (big boost + turbo upgrades). Last I checked, people were getting around this my drilling and tapping the IM, and installing a 5th injector, which complicates tuning further.
 

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