This is very informative! I just recently ran across your channel and while you don't have the flashy production that other channels might have the information presented and non-biased fact based information is super refreshing, and is frankly more important than the fancy set loud, dub-step intro music, and seizure inducing graphics. Definitely keep it up!!!! Good job guys.
Your vids are great... i wish some of the SUBI forum members would reference these instead of misinformation and in-fighting on which way is better. Thank you for this!
Thanks very much Luis! If any of our videos can answer questions, or gets good information out into the community, then we have accomplished our goal. Thank you for watching!
I started my build about 6 months ago and my engine is getting a complete build. I wish this video and several others on your channel were available when I first started. Would've saved me some big headaches and a lot of money. I look forward to more videos!
Thanks Brian! We are working to get more videos up, and if there is anything specific that you are curious about, let us know and maybe we can cover it. Our goal is to get as much information out there as possible to help people like yourself with their projects.
I went with an ej207, built/forged bottom end, 272 lift cams, Tomei m7960, and 1000cc injectors. As of this comment it's almost finished, and I really hope I can meet my goal of 400/400 on 91CDN. Your videos really helped me understand these motorcycle motors, I.E. how much the factory PCV system barely keeps up with OEM specs.
I agree, I didn't think twice about it and automatically thought forged pistons were just built to last longer and handle more power. As true as that might be I never thought that it would cause wear to another component.
My 14 WRX spun a bearing two weeks before this video was published! I wanted to do the work myself but man it was stressful! Glad I had a buddy to guide me over the phone. 7 weeks later and luckily it started up on the first try. After watching this video I am glad I stayed with a stock block with modest power goals. I have the turbo and nearly ALL tge supporting mods to go over 300whp but my hope is that the engine will make 300whp without working so hard. I drive 30,000 miles/year. Thanks for the tech tips!!
You sound like my dad when I bought my very 1st wrx at 16.. few wrxs, evos and rx7s later... and I'm still the same.. hard on the gear🤣 and thats why Drivers Habits are the biggest killers of cars and budgets.. Awesome videos bro I must say.. keep up the good work..
This is super great! I feel like the shops around here just prescribe forged pistons no matter what - which is frustrating because I know it's not that black and white especially at the power levels your describe, which 90% of people would be more than happy with 300-350whp
Thanks! Forged pistons and built engine's definitely have their place. But there is just a little more to the decision than is usually talked about, and we wanted to try to get that information out there so people can make the best decision. Thanks for your feedback!
Thank you for this video! This brings STI tuning to perspective for me. I was thinking no more than 350whp on stock engine (once my car is out of warranty). I never liked the idea of mixing and matching parts that Subaru engineers never planned to go in the EJ.
Another great video. I can honestly appreciate this video. I just started my build, I ended up going with a iag stage 2 block. My goal is 450hp, not sure with what turbo I should go with. I want a direct bolt on.
Thanks Miguel. That is a good block as a starting point certainly. For turbos, I'd recommend looking at a small 30R with external gate if you are wanting to go rotated, or if you are looking for stock location, something like the Turbo Dynamics MDX555-450: www.flatironstuning.com/p-3943-turbo-dynamics-mdx555-450-hybrid-turbocharger-450hp.aspx Or the Blouch Dominator 1.5 XT-R: www.flatironstuning.com/p-2306-blouch-dominator-15xt-r-ball-bearing-turbocharger-for-the-subaru-wrxsti.aspx And of course you will need the supporting fueling and cooling mods to go along with the turbo. Hope that helps, and good luck with the build! Thanks for watching!
FlatironsTuning thanks alot. I'm planning on going flex fuel. Quick question, do you think I can get away with stock heads and cams or should I port them and get aftermarket cams (stage 2)?
Hello Miguel. First, what heads do you have? On the 2.5 liter engines, you can get well over 400 whp with stock heads and cams. And for your goal for 450, I'd say that the stock 2.5L heads and cams should be fine. I'd start to look at cams if/when you start to shoot for more than 500 whp.
When you say "350 wheel horsepower", what dyno are we talking? I have a tuner with a mustang dyno that basically said there's no way I'm getting over 275 to the wheels unless we install a larger turbo and supporting mods. I was under the impression installing a larger turbo was basically death for the cast pistons.
Thanks for your question. With a good tune, going to a reasonably larger turbo on the stock block can work well. The power goals and tune just have to be good. With those in place, the stock block should be reliable in the 320 - 350 whp range. Hope that helps and Stay Tuned!
It can be done, but it is not easy at all. There are not nearly as many parts for the 6 cylinder engines to support forced induction as you would think, but some are doing it. Our friends at ASF Machine have done it. Check out this link: th-cam.com/video/kiBjv9u8mNc/w-d-xo.html
In the process of rebuilding someone else's build on a 02 wrx hybrid, I'm doing complete tear down. It has 257 block with wiseco pistons, eagle rods, with 205 heads sized to 52cc, 1000cc injectors, td05 turbo, Cobb accesstuner. This setup will put me at 8.9:1cr not sure if I should drop down to 8.5:1cr. Looking for around 325-400hp. Car will be used for auto x and drag strip. What is your suggestion for cr and anything else? I will be ordering parts from you guys at flatiron just because of the knowledge you have with these cars. Great videos, keep it up!
Thanks for your question! For this specific of a question, I'd recommend calling us or e-mailing us directly so that we can go into detail with you. The short answer is that ideal compression ratio largely depends on the fuel that you will be running. If you are running E85, or a largely detonation/pre-ignition fuel, then there can be some nice gains made from increasing your compression ratio. However, if you are running standard pump-gas, our experience has been that you are best to stay close around the OEM compression ratio. Thanks for watching, and thanks for your business!
Thank you! All the info you stated is spot on with what my tuner said. Very reassuring. I definitely trust him even more now. I'm going for 450whp. We are over building and tuning it conservatively on both acn91 and e85(full flex fuel kit). Since I trust your judgement. Would the block(iag 3 tuff) last longer with this type of approach or is it overkill? I still know that I'll be doing a refresh around 80k give or take. My tuner was very straight forward with that but when I suggested a less "strong" block he suggested that I not go that direction. I will be tracking it 5 or 6 times a year or more(California weather). I know it's kind of a hard question to answer(subjective) but your opinion/thoughts are greatly appreciated. Oh and I upgraded EVERYTHING to support this powa' Cooling ,exhaust, fueling, turbo, oiling and induction and I mean everything. Thanks.
if one builds an engine with a bunch of aftermarket uprated parts apart from having the installation of the components being done right, and assuming all the parts are the perfect fit down to the oil pickup, the pan and the oil pump then it is going to be a motor that most likely will last if ran and mantained properly. But then again the forged pistons and the extra clearence would eventually wear it down to a point where the engine wont perform as it should... is there a way to mitigate wear from a bit looser pistons? Im thinking maybe inserting the right sleeves could help not only reinforce the cylinders as deck inserts also do but as I would think the right sleeves surely must be harder and tougher than the original bore material and might help extend the life of the cylinders or no not really?
Thanks for your question. There are low expansion forged pistons that are designed to run tighter piston to wall tolerance, and that would be one direction to go if you are looking for more life out of the engine compared ability to hold maximum power. You really don't want to deviate from a manufacturer's spec's on PTW tolerance. Here are the RCM low expansion pistons for instance: www.flatironstuning.com/rcm-omega-piston-set-low-expansion-ej25 It all depends on your overall goals really. Hope that helps, and Stay Tuned!
I have a head gasket failure. Should i throw forge pistons or leave it? i made it up to 133k mile from factory brand new the only mods i had was an intake and accessport. my power goals is 350-380whp its my daily.
Thanks for your question. The biggest variable there is how many miles you want to get out of a new engine. If you are hoping to get close to 100k miles, sticking with a stock block is the safest bet. You would just want to reduce the power goals slightly to keep the engine reliable. Hope that helps and Stay Tuned!
What about a hypothetical question-what if you have a built short block, say capable of 500+HP and have it tuned to 350HP, change oil every 3K Miles, Use Subaru coolant[with conditioner], do only occasional[as in rare] hooning, would the engine last as long as a stock engine?
Thanks for your question. It is hard to say for sure. There are definitely people that are able to get up to 100,000 or so miles on a built block. But there isn't a clear formula to do that. The biggest factor would be to monitor oil for consumption, and to keep an eye on your PCV system. Another thing to consider is that the higher the power target of a block, typically the loser the tolerances. This can apply to the bearings, ring gap, etc. Those lose tolerances generally will add up to slightly accelerated wear over time, which can also shorten the life of an engine. I hope that helps, and Stay Tuned!
@@FlatironsTuning Thanks so much for enlightening us about the pitfalls of a built engine. In essence, due to its looser tolerances, having a built engine becomes a "roll of the dice" as far as longevity is concerned. A trade off between having more power [and bragging rights] and a "relatively" weaker engine that allows you to sleep better at night. This endeavor then is suited for people with deep pockets willing to do an engine rebuild say every 60K-80K miles- that probably at the most ideal circumstances. Thanks again!
@@4rct1c9Ic3m4n Overall, the reason that we made this video was to address the perception that you addressed with your initial question. There is definitely a perception that if you build the engine to hold tons of power, but you run it at a fraction of that, it will last a long, long time. Over the years, we had enough people that got burnt by that misconception that we wanted to put out a better guide for making the decision of how far you want to go with a build where reliability is concerned. Glad that it helped, and Stay Tuned!
@@FlatironsTuning do you have any thoughts on the Type RA block found in the 19+ STIs? Seems that people have been successfully running over 400whp on them, though for how long it'll last it's probably too soon to say. I'm not sure how the tolerances compare but is it possible that it could provide an OEM level of longevity while also allowing a higher power level?
@@gorbasho You may have noticed that we are using an RA block in our Pikes Peak car now. Here is a link to the details of the build, and you can take a look at our dyno sheet for reference: www.flatironstuning.com/blog/a-detailed-look-at-the-build-of-our-2021-pikes-peak-race-car We are pushing just above 400 whp, and I'd say that if you have a race car, this might be a viable option if you wouldn't want to ever push mush further than that in terms of power. But for a street car, I'd definitely say it is far too early to say that a Type RA block would be a solid choice with that kind of power target. I think I'd still recommend looking at a built block with that kind of power target. Hope that helps and Stay Tuned!
Right now on your website my cart is about 3,650 with parts for my build am looking for reliability engine and maybe 375HP my question do you guys offer remote tuning
Thanks for your question. We do not work on or Tune customer cars unfortunately. But we may be able to help you find a Tuner to work with. Thanks for your business and thanks for your support! Stay Tuned!
I did cobb 20g turbo, killer b headers, 1050 injectors, fuel pump, q300 cat back, ets tmic, cobb intake, cobb up pipe, koyo radiator, IAG AOS, IAG oil pick up, Killer B turbo inlet, VSC radiator hoses, 3 port, 04 sti regular and pro tune. I put down around 360whp on pump with stock cats on a conservative tune on 15 sti engine.
Very well explained. I have a ej25 but im a bit worried of ringland and i was thinking of upgrading to forged piston and acl race main and cone bearing. Keeping stock VF52 probably a good tune at 16psi or more. Should i get forged rods too? Is it a wise upgrade....? Looking for 320hp from crank and an engine to last!
Thanks for your question. If you are just running a VF52, then forged pistons should not be needed. And as stated in the video, the other thing to keep in mind with forged pistons is that they typically come with a shorter overall life expectancy than the stock pistons. Hope that helps, and thanks for watching!
@@FlatironsTuning Oh! You actually replied, thanks. Im going for street tune (stage1) my ej25 for 300hp, i hope rings wont give up. Going to invest for quality tune. Thanks for the tip.
@@deom2i Sounds good. If you are going to get a street tune, you may want to go through the video that we made going over the advantages and disadvantages of the different types of tunes too: th-cam.com/video/0YqStaVQg_c/w-d-xo.html But yes, at that power level, you should be fine with a good tune. Good luck, and thanks for watching!
Thanks for your question Rob. With that small a turbo, I'd just stick with the stock cams. If you put in an aggressive cam, you will start to lose low end torque which that turbo does well, and then at higher rpm when the cam really starts to to work, that turbo will fall out of its efficiency. Hope that helps, and thanks for watching!
I have an ej20 just did head gasket replacement, its a non turbo would like to put a small turbo with 4 to 6 pounds of boost..whats the simple way to do it without doing the whole engine again
Thanks for your question. Unfortunately there is no easy way to do that, and if you don't go in and build the engine, your gains will be minimal, and the potential for engine failure is moderately high. Years ago, there were a number of people that were supercharging their Subaru's, and if anything, I'd say that is what you would want to look into. It is much easier to deal with on an NA car compared to a turbocharger. But even then, there is a pretty high risk to your engine. Now that turbo swaps are so prevalent, I'd say that if you really want to go down this road, that is what you want to look at. Hope that helps, and thanks for watching!
So I've got a question for you, I recently did a hybrid ej255 with 251 heads and intake. I'm going standalone soon and want to run around 14psi. My valve guides seem to be leaking so I figure when I go to pull the heads I should upgrade my springs and valves. Do you have an approximation on how much power the stock 251 head springs can handle? Or is it more of a case of high they can rev before valve float? I'm on 5psi right now till I get my ecu tuned
Thanks for your question Chris. I'm going to say that I don't have enough experience to give you a good answer on that one. I'd recommend talking to ASF Machine. They played with the 2.5 Liter SOHC heads a good deal a few years ago, and they should be able to help you out. Delta Cams would be another good place to talk to. Hope that helps, and thanks for watching!
Great no-fluff videos, with valuable information on the subject! I'd love to get some input on engine longevity for a built block with different types of forged pistons. 2618 vs. 4032 alloy? My understanding is that 4032's run a clearance closer to stock, so how much longevity does that equate to vs. a 2618? p.s. love the new(ish?) website storefront - haven't ordered anything since late 2014, it's a big improvement!
Thanks for your question. Looking as simple wear, yes, an alloy that lets you run a tighter piston to wall clearance would be more ideal. You will always need to pay attention to the piston manufacturer's specifications, and use that to compare one piston to another. When you are looking at power, that is a somewhat different matter. You need to look at what the manufacturer says about how much pressure/power the piston can withstand. From what we have seen, in many cases the alloy that does allow for tighter PTW clearances will be rated at lower overall power. Ultimately, if you are looking at a couple different pistons, we would recommend talking to the piston manufacturer directly about their specs, and make your decision with that information. Good luck with your build, and thanks again for your question!
Been thinking about going with an outfront 2.14 stroker with big port heads. Any experience with that setup? I've been back and forth on what turbo setup to go with. It's not a daily driver so it wouldn't see crazy amounts of miles and I'm always very meticulous with oil changes. I've been at about 300whp for a couple years and have just always wanted more.
Thanks for your question. We have helped a number of people with 2.1 strokers over the years. The biggest points that I could give are these. First, they seem to be happier on E85 or race gas compared to pump gas. As far as torque goes, it will be easier to make more low end torque with a 2.5 liter engine, but the 2.1 stroker can be a bit happier to spin at a higher rpm as long as it is balanced, and the heads are built to match. They can definitely be fun engines. We were just at the track with Lucas from Wild Westy, and his GC has a 2.1 stroker that is making about 360 whp on E85. It is a fun car! Stay tuned for the video. Hope that helps, and thanks for watching!
Wow I didn't realise my ej255 was capable of 350 hp. Surely it wouldn't be that reliable and wouldn't last that long, won't the pistons give out real quick?
Thanks for your question Jordan. First, remember that a reliable tune is a critical piece to keep the engine reliable. And 350 whp is an upper limit. But if you have a good tune, the car can be pretty reliable at that power level. If you dial it back to low 300's (like 320 - 330 whp) then your chances of reliability are increased too. I hope that helps, and thanks for watching!
@@FlatironsTuning okay thanks for your response. Say at 330 hp, what kind of life span are we talking provided the car has a good tune and is a street driven car driven only 2-3 times a week but the power would be used regularly. Thanks for your helpful comments.
Thanks for your question. Roughly speaking, I would say so. Though on a 2.0 liter engine it has a much different driveability at even 300 whp compared to the 2.5 liter engines. Most of the time, once you get close to 300 whp on the 2.0 liter engine, the compromises needed to push further just don't fit for most people. Hope that helps and Stay Tuned!
i have a bugeye wrx, still on its factory motor. possibly looking 300hp, 320 max. what would you recommend be the best upgrades to get it to run the best for that power level? already got a mishimoto front mount + their short ram intake, not yet on the car as I don't have the money for the tune yet. umpire uel catless headers/up pipe (same story as fmic). and have been looking at things like better fuel pump, possibly something with a flow rate of 355lph (looking e85 compatible maybe as well) , bigger injectors and swap the tdo4 with a td05. the goal is the have mods be able handle more than what I want out of it to hopefully not have things so over worked if i do a spirited drive.
Thanks for your question. On the 2.0 liter engine, getting to 300 whp will require a bigger turbo (I'd say a TD05 20G at a minimum), and the result is typically a significant loss of usable power band. And If you are on a higher mileage engine, you may not want to stress that block that much. I'd say that one of the best turbos for the 2.0 is a 16G, which should get you around 250 whp with a good tune. That makes the car a lot more fun, and it can still be reliable with a good tune. Hope that helps, and thanks for watching!
@@FlatironsTuning awesome!! cheers for that. yeh not looking for crazy numbers. just looking to wake it up a little more and run more "efficiently" with less air flow restrictions and better cooling. would you think a 3 port boost controller/solenoid would be worth the investment as well? i've heard they help alot when you get a tune done to have more predictable and consistent boost levels
@@sebsshenanigans They can, but it definitely comes down to the turbo itself much more than the controller. But if you are getting a tune done, it is not a bad idea. In a pinch, get one, and set it aside so you have it if you need it. Start with the stock solenoid and see if that will get the job done.
Thanks for your question. We haven't worked with enough of those engines to give you a solid answer I'm afraid. A lot of that would come down to what the piston to wall tolerance of the factory pistons was. They would definitely be able to handle more power than a block that came with cast pistons. But if the PTW tolerance is tight to keep noise and wear to a minimum, that may be an issue above a certain point. Hope that helps and Stay Tuned!
That is a hard question. I'd say that if your EJ207 is in good working order, there is not necessarily any need to go in and replace it. The EJ25 cylinders are a bit smaller than the EJ207 (especially compared to the thick wall EJ207 from the newer blocks), but they are not a limiting factor below about 550 whp. Generally speaking, the decision about what displacement block would be best for you often comes down to power goal and desired power band. I hope that helps, and Stay Tuned!
@@FlatironsTuning am actually planning for a forged daily drive build. Minimal lag with some serious kick to the back upon full boost. Was contemplating whether to go for a full 2.0 forged, 2.1 stroker or a 2.5 forged. As per the above, my major concern in 2.5 build is the liner crack issue. 2.1 gonna be an issue to me in sourcing for the offset wrist pin piston. 2.0 straightforward build but bored? Aiming at 400-450whp. Day dreaming of a flat 300-400wtq curve (wondering is it possible?) Yet to decide on turbo.
If I'm looking to do a hybrid build using wrx heads and je pistons would you recommend installing the pistons on an new oem sti short block or at that point should I go with something like iags closed deck case halves and new rods etc? Only looking for around 375 hp.
If that is your power goal, you are just past the point where stock pistons would be at there limit, requiring forged pistons. You could certainly put them into a new OEM block, or build a new OEM case. You don't need a closed deck block. That is only needed if you are looking to push past 550 whp or so. You would not get any benefit for it at your power goal, and you would be adding a significant amount of cost to your engine build. I hope that helps, and good luck with your build!
FlatironsTuning Thank you, for that 350-375 hp range would you always recommend starting with a new oem shortblock or is rebuilding a spun bearing or similar 257 okay to do for that hp? Not really looking for insane reliability because it's not going to be daily driven at all more for just autox and track events.
Well, the first step with any used block is to have a quality machine shop inspect it. If it is good, but needs to be over bored, I'd recommend not going to more than 99.75mm. you really want as much material in the cylinders as possible. 100mm is okay for moderate builds, but not ideal. For bigger power (450 whp+), starting with a new case is a better bet. But overall, making sure that there are no issued with the block is critical before you start machining it.
Im building an ej205 power level is 300whp with stock 07 sti turbo (vf43). Im planning to go forged rods/ piston, stock crank, and stock heads. I need opinions.
Forged is overkill for those goals. Might as well go bigger with the turbo, or keep stock shortblock. Regardless, be sure to upgrade to STi / 06+ WRX oil pan, or an aftermarket pan
Thanks for your question. That is a slightly hard question to answer. It isn't as easy to get an EJ205 above 300 whp with a good usable power-band, so not as many people have done that so there is less information out there about it. I think that I'd say that 300 whp can definitely be reliable on an EJ205 engine, but getting to that power level and still having a good powerband is the hard part. You can certainly do it with a 20G turbo, but on the 2.0 liter, you end up with minimal power below about 3,500 rpm. I hope that helps and Stay Tuned!
My favorite turbo for the EJ205 is something like an Evo-3 16G or Blouch's 16G XT-R. That will give you good power from 3,800 rpm on, and will pull to red-line. You should be able to make between 240 whp and 260 whp on that as well. Hope that helps!
Any idea on short block recommendations when my OEM engine goes. Right now it's just stage 2 mods but when it goes I'd like to get equal lengths headers, and a cobb20g turbo. OEM block with safe tune or IAG stage 2 block?
Thanks for your question. If you are looking at a 20G turbo, that falls to the top of the range that the stock block can support. If you don't plan on trying to push past 350 whp, then I'd say that would make sense for your build. If you want to have the option to go for more power, then the IAG block might make more sense, but you would have to make sure that you will be building to that power level in the reasonable life-span of the engine. I hope that helps, and thanks for watching!
Thanks for the vote of confidence, but engine building is not in my skill-set yet. If you need an engine built, we can point you to some experts that can take care of you ;-) Thanks for watching and Stay Tuned!
This is very informative! I just recently ran across your channel and while you don't have the flashy production that other channels might have the information presented and non-biased fact based information is super refreshing, and is frankly more important than the fancy set loud, dub-step intro music, and seizure inducing graphics. Definitely keep it up!!!! Good job guys.
Awesome compliment. Thanks Henry!
@@FlatironsTuning Your welcome and I say this as a former deal tech for the other Manf that makes split case engines.
Your vids are great... i wish some of the SUBI forum members would reference these instead of misinformation and in-fighting on which way is better. Thank you for this!
Thanks very much Luis! If any of our videos can answer questions, or gets good information out into the community, then we have accomplished our goal.
Thank you for watching!
I started my build about 6 months ago and my engine is getting a complete build. I wish this video and several others on your channel were available when I first started. Would've saved me some big headaches and a lot of money. I look forward to more videos!
Thanks Brian! We are working to get more videos up, and if there is anything specific that you are curious about, let us know and maybe we can cover it. Our goal is to get as much information out there as possible to help people like yourself with their projects.
I went with an ej207, built/forged bottom end, 272 lift cams, Tomei m7960, and 1000cc injectors. As of this comment it's almost finished, and I really hope I can meet my goal of 400/400 on 91CDN. Your videos really helped me understand these motorcycle motors, I.E. how much the factory PCV system barely keeps up with OEM specs.
Awesome! Very glad that our videos were a help, and hope that you have great luck with your build.
Thanks for watching and Stay Tuned!
The point about forged pistons clearance and built blocks shortening engine life was very interesting.
I agree, I didn't think twice about it and automatically thought forged pistons were just built to last longer and handle more power. As true as that might be I never thought that it would cause wear to another component.
Thanks Edward!
My 14 WRX spun a bearing two weeks before this video was published! I wanted to do the work myself but man it was stressful! Glad I had a buddy to guide me over the phone. 7 weeks later and luckily it started up on the first try. After watching this video I am glad I stayed with a stock block with modest power goals. I have the turbo and nearly ALL tge supporting mods to go over 300whp but my hope is that the engine will make 300whp without working so hard. I drive 30,000 miles/year. Thanks for the tech tips!!
This video just saved me hundreds of dollars. Thank you
Very glad that you found the video and that it was helpful!
Thanks for watching and Stay Tuned!
You sound like my dad when I bought my very 1st wrx at 16.. few wrxs, evos and rx7s later... and I'm still the same.. hard on the gear🤣 and thats why Drivers Habits are the biggest killers of cars and budgets..
Awesome videos bro I must say.. keep up the good work..
Thanks very much, and thanks for watching.
Stay Tuned!
This is super great! I feel like the shops around here just prescribe forged pistons no matter what - which is frustrating because I know it's not that black and white especially at the power levels your describe, which 90% of people would be more than happy with 300-350whp
Thanks! Forged pistons and built engine's definitely have their place. But there is just a little more to the decision than is usually talked about, and we wanted to try to get that information out there so people can make the best decision.
Thanks for your feedback!
A lot of subie owners DO NOT understand this concept and wonder why their motor went 💥
Thank you for this video! This brings STI tuning to perspective for me. I was thinking no more than 350whp on stock engine (once my car is out of warranty). I never liked the idea of mixing and matching parts that Subaru engineers never planned to go in the EJ.
Warranty ? Who buys a car to build and gets a warranty? Your a ricer
Thank you for all these videos, you guys are a wealth of knowledge.
Thanks Alex, and thanks for watching!
@Alex - you don't need brakes with a fast car (joking)
But if I keep the stock brakes I can afford more HP. LoL
Another great video. I can honestly appreciate this video. I just started my build, I ended up going with a iag stage 2 block. My goal is 450hp, not sure with what turbo I should go with. I want a direct bolt on.
Thanks Miguel. That is a good block as a starting point certainly. For turbos, I'd recommend looking at a small 30R with external gate if you are wanting to go rotated, or if you are looking for stock location, something like the Turbo Dynamics MDX555-450:
www.flatironstuning.com/p-3943-turbo-dynamics-mdx555-450-hybrid-turbocharger-450hp.aspx
Or the Blouch Dominator 1.5 XT-R:
www.flatironstuning.com/p-2306-blouch-dominator-15xt-r-ball-bearing-turbocharger-for-the-subaru-wrxsti.aspx
And of course you will need the supporting fueling and cooling mods to go along with the turbo.
Hope that helps, and good luck with the build! Thanks for watching!
FlatironsTuning thanks alot. I'm planning on going flex fuel. Quick question, do you think I can get away with stock heads and cams or should I port them and get aftermarket cams (stage 2)?
Hello Miguel. First, what heads do you have? On the 2.5 liter engines, you can get well over 400 whp with stock heads and cams. And for your goal for 450, I'd say that the stock 2.5L heads and cams should be fine. I'd start to look at cams if/when you start to shoot for more than 500 whp.
FlatironsTuning man, thank you so much! Hope your channel keeps growing, thank you for your great information.
FlatironsTuning 2006 sti
When you say "350 wheel horsepower", what dyno are we talking? I have a tuner with a mustang dyno that basically said there's no way I'm getting over 275 to the wheels unless we install a larger turbo and supporting mods. I was under the impression installing a larger turbo was basically death for the cast pistons.
Thanks for your question. With a good tune, going to a reasonably larger turbo on the stock block can work well. The power goals and tune just have to be good.
With those in place, the stock block should be reliable in the 320 - 350 whp range.
Hope that helps and Stay Tuned!
What about just snatch out the 2.5 and drop in a ez30 or ez36 with the factory sti turbo
Aftermarket with the EZ series, despite the obvious benefits, are basically close to zero. A travesty really.
It can be done, but it is not easy at all. There are not nearly as many parts for the 6 cylinder engines to support forced induction as you would think, but some are doing it.
Our friends at ASF Machine have done it.
Check out this link:
th-cam.com/video/kiBjv9u8mNc/w-d-xo.html
Amazing info on these vids,Subbed.
Very glad you found us. Be sure to pass it on.
Thanks for watching and Stay Tuned!
@@FlatironsTuning Sure will,love the subaru videos.
I’m on engine #4 have 44k kilometres on car …. 2006 sti that’s only been track driven
Excellent explanation. good info. and good videos.
Thanks Hector!
In the process of rebuilding someone else's build on a 02 wrx hybrid, I'm doing complete tear down. It has 257 block with wiseco pistons, eagle rods, with 205 heads sized to 52cc, 1000cc injectors, td05 turbo, Cobb accesstuner. This setup will put me at 8.9:1cr not sure if I should drop down to 8.5:1cr. Looking for around 325-400hp. Car will be used for auto x and drag strip. What is your suggestion for cr and anything else? I will be ordering parts from you guys at flatiron just because of the knowledge you have with these cars. Great videos, keep it up!
Thanks for your question! For this specific of a question, I'd recommend calling us or e-mailing us directly so that we can go into detail with you.
The short answer is that ideal compression ratio largely depends on the fuel that you will be running. If you are running E85, or a largely detonation/pre-ignition fuel, then there can be some nice gains made from increasing your compression ratio. However, if you are running standard pump-gas, our experience has been that you are best to stay close around the OEM compression ratio.
Thanks for watching, and thanks for your business!
I know it’s a old video. But what about the ej205. How robust are they. And could you make around 350 on a stock block
Another great video 👍
Thanks for watching Chris!
Thank you! All the info you stated is spot on with what my tuner said. Very reassuring. I definitely trust him even more now. I'm going for 450whp. We are over building and tuning it conservatively on both acn91 and e85(full flex fuel kit). Since I trust your judgement. Would the block(iag 3 tuff) last longer with this type of approach or is it overkill? I still know that I'll be doing a refresh around 80k give or take. My tuner was very straight forward with that but when I suggested a less "strong" block he suggested that I not go that direction. I will be tracking it 5 or 6 times a year or more(California weather). I know it's kind of a hard question to answer(subjective) but your opinion/thoughts are greatly appreciated. Oh and I upgraded EVERYTHING to support this powa' Cooling ,exhaust, fueling, turbo, oiling and induction and I mean everything. Thanks.
if one builds an engine with a bunch of aftermarket uprated parts apart from having the installation of the components being done right, and assuming all the parts are the perfect fit down to the oil pickup, the pan and the oil pump then it is going to be a motor that most likely will last if ran and mantained properly.
But then again the forged pistons and the extra clearence would eventually wear it down to a point where the engine wont perform as it should... is there a way to mitigate wear from a bit looser pistons?
Im thinking maybe inserting the right sleeves could help not only reinforce the cylinders as deck inserts also do but as I would think the right sleeves surely must be harder and tougher than the original bore material and might help extend the life of the cylinders or no not really?
Thanks for your question. There are low expansion forged pistons that are designed to run tighter piston to wall tolerance, and that would be one direction to go if you are looking for more life out of the engine compared ability to hold maximum power.
You really don't want to deviate from a manufacturer's spec's on PTW tolerance.
Here are the RCM low expansion pistons for instance:
www.flatironstuning.com/rcm-omega-piston-set-low-expansion-ej25
It all depends on your overall goals really.
Hope that helps, and Stay Tuned!
I have a head gasket failure. Should i throw forge pistons or leave it? i made it up to 133k mile from factory brand new the only mods i had was an intake and accessport. my power goals is 350-380whp its my daily.
Thanks for your question. The biggest variable there is how many miles you want to get out of a new engine. If you are hoping to get close to 100k miles, sticking with a stock block is the safest bet. You would just want to reduce the power goals slightly to keep the engine reliable.
Hope that helps and Stay Tuned!
Forged are fun but you can't beat a constantly happy daily cammed ej207, check mine out
Thanks for watching and Stay Tuned!
makes sense - sensible
best thing in boulder, bar none
What about a hypothetical question-what if you have a built short block, say capable of 500+HP and have it tuned to 350HP,
change oil every 3K Miles, Use Subaru coolant[with conditioner], do only occasional[as in rare] hooning, would the engine last
as long as a stock engine?
Thanks for your question. It is hard to say for sure. There are definitely people that are able to get up to 100,000 or so miles on a built block. But there isn't a clear formula to do that.
The biggest factor would be to monitor oil for consumption, and to keep an eye on your PCV system.
Another thing to consider is that the higher the power target of a block, typically the loser the tolerances. This can apply to the bearings, ring gap, etc.
Those lose tolerances generally will add up to slightly accelerated wear over time, which can also shorten the life of an engine.
I hope that helps, and Stay Tuned!
@@FlatironsTuning Thanks so much for enlightening us about the pitfalls of a built engine. In essence, due to its looser tolerances, having a built engine
becomes a "roll of the dice" as far as longevity is concerned. A trade off between having more power [and bragging rights] and a "relatively" weaker engine
that allows you to sleep better at night. This endeavor then is suited for people with deep pockets willing to do an engine rebuild say every 60K-80K miles-
that probably at the most ideal circumstances. Thanks again!
@@4rct1c9Ic3m4n Overall, the reason that we made this video was to address the perception that you addressed with your initial question. There is definitely a perception that if you build the engine to hold tons of power, but you run it at a fraction of that, it will last a long, long time.
Over the years, we had enough people that got burnt by that misconception that we wanted to put out a better guide for making the decision of how far you want to go with a build where reliability is concerned.
Glad that it helped, and Stay Tuned!
@@FlatironsTuning do you have any thoughts on the Type RA block found in the 19+ STIs? Seems that people have been successfully running over 400whp on them, though for how long it'll last it's probably too soon to say. I'm not sure how the tolerances compare but is it possible that it could provide an OEM level of longevity while also allowing a higher power level?
@@gorbasho You may have noticed that we are using an RA block in our Pikes Peak car now. Here is a link to the details of the build, and you can take a look at our dyno sheet for reference:
www.flatironstuning.com/blog/a-detailed-look-at-the-build-of-our-2021-pikes-peak-race-car
We are pushing just above 400 whp, and I'd say that if you have a race car, this might be a viable option if you wouldn't want to ever push mush further than that in terms of power.
But for a street car, I'd definitely say it is far too early to say that a Type RA block would be a solid choice with that kind of power target. I think I'd still recommend looking at a built block with that kind of power target.
Hope that helps and Stay Tuned!
Right now on your website my cart is about 3,650 with parts for my build am looking for reliability engine and maybe 375HP my question do you guys offer remote tuning
Thanks for your question. We do not work on or Tune customer cars unfortunately. But we may be able to help you find a Tuner to work with.
Thanks for your business and thanks for your support!
Stay Tuned!
I did cobb 20g turbo, killer b headers, 1050 injectors, fuel pump, q300 cat back, ets tmic, cobb intake, cobb up pipe, koyo radiator, IAG AOS, IAG oil pick up, Killer B turbo inlet, VSC radiator hoses, 3 port, 04 sti regular and pro tune. I put down around 360whp on pump with stock cats on a conservative tune on 15 sti engine.
Very well explained.
I have a ej25 but im a bit worried of ringland and i was thinking of upgrading to forged piston and acl race main and cone bearing. Keeping stock VF52 probably a good tune at 16psi or more.
Should i get forged rods too?
Is it a wise upgrade....?
Looking for 320hp from crank and an engine to last!
Thanks for your question. If you are just running a VF52, then forged pistons should not be needed. And as stated in the video, the other thing to keep in mind with forged pistons is that they typically come with a shorter overall life expectancy than the stock pistons.
Hope that helps, and thanks for watching!
@@FlatironsTuning Oh! You actually replied, thanks.
Im going for street tune (stage1) my ej25 for 300hp, i hope rings wont give up. Going to invest for quality tune. Thanks for the tip.
@@deom2i Sounds good. If you are going to get a street tune, you may want to go through the video that we made going over the advantages and disadvantages of the different types of tunes too:
th-cam.com/video/0YqStaVQg_c/w-d-xo.html
But yes, at that power level, you should be fine with a good tune.
Good luck, and thanks for watching!
What are good cams for a stock jdm ej205 with avcs, the motor has a 16g blouch turbo, IAG fuel rails and 1000cc injectors, catless tbe and uppipe
Thanks for your question Rob. With that small a turbo, I'd just stick with the stock cams. If you put in an aggressive cam, you will start to lose low end torque which that turbo does well, and then at higher rpm when the cam really starts to to work, that turbo will fall out of its efficiency.
Hope that helps, and thanks for watching!
what would be a great setup for a 350-400whp tuned ej255? weekend driven
I have an ej20 just did head gasket replacement, its a non turbo would like to put a small turbo with 4 to 6 pounds of boost..whats the simple way to do it without doing the whole engine again
Thanks for your question. Unfortunately there is no easy way to do that, and if you don't go in and build the engine, your gains will be minimal, and the potential for engine failure is moderately high.
Years ago, there were a number of people that were supercharging their Subaru's, and if anything, I'd say that is what you would want to look into. It is much easier to deal with on an NA car compared to a turbocharger.
But even then, there is a pretty high risk to your engine.
Now that turbo swaps are so prevalent, I'd say that if you really want to go down this road, that is what you want to look at.
Hope that helps, and thanks for watching!
So I've got a question for you, I recently did a hybrid ej255 with 251 heads and intake. I'm going standalone soon and want to run around 14psi. My valve guides seem to be leaking so I figure when I go to pull the heads I should upgrade my springs and valves. Do you have an approximation on how much power the stock 251 head springs can handle? Or is it more of a case of high they can rev before valve float? I'm on 5psi right now till I get my ecu tuned
Thanks for your question Chris. I'm going to say that I don't have enough experience to give you a good answer on that one. I'd recommend talking to ASF Machine. They played with the 2.5 Liter SOHC heads a good deal a few years ago, and they should be able to help you out.
Delta Cams would be another good place to talk to.
Hope that helps, and thanks for watching!
@@FlatironsTuning no worries thanks alot for the info! Mad quick reply as well. Love your videos
Great no-fluff videos, with valuable information on the subject! I'd love to get some input on engine longevity for a built block with different types of forged pistons. 2618 vs. 4032 alloy? My understanding is that 4032's run a clearance closer to stock, so how much longevity does that equate to vs. a 2618?
p.s. love the new(ish?) website storefront - haven't ordered anything since late 2014, it's a big improvement!
Thanks for your question. Looking as simple wear, yes, an alloy that lets you run a tighter piston to wall clearance would be more ideal. You will always need to pay attention to the piston manufacturer's specifications, and use that to compare one piston to another. When you are looking at power, that is a somewhat different matter. You need to look at what the manufacturer says about how much pressure/power the piston can withstand. From what we have seen, in many cases the alloy that does allow for tighter PTW clearances will be rated at lower overall power.
Ultimately, if you are looking at a couple different pistons, we would recommend talking to the piston manufacturer directly about their specs, and make your decision with that information.
Good luck with your build, and thanks again for your question!
Been thinking about going with an outfront 2.14 stroker with big port heads. Any experience with that setup? I've been back and forth on what turbo setup to go with. It's not a daily driver so it wouldn't see crazy amounts of miles and I'm always very meticulous with oil changes. I've been at about 300whp for a couple years and have just always wanted more.
Thanks for your question. We have helped a number of people with 2.1 strokers over the years.
The biggest points that I could give are these.
First, they seem to be happier on E85 or race gas compared to pump gas.
As far as torque goes, it will be easier to make more low end torque with a 2.5 liter engine, but the 2.1 stroker can be a bit happier to spin at a higher rpm as long as it is balanced, and the heads are built to match.
They can definitely be fun engines. We were just at the track with Lucas from Wild Westy, and his GC has a 2.1 stroker that is making about 360 whp on E85. It is a fun car! Stay tuned for the video.
Hope that helps, and thanks for watching!
How much wear (in % terms vs a 325hp) for a 350kW (@wheels) engine ?
Wow I didn't realise my ej255 was capable of 350 hp. Surely it wouldn't be that reliable and wouldn't last that long, won't the pistons give out real quick?
Thanks for your question Jordan. First, remember that a reliable tune is a critical piece to keep the engine reliable. And 350 whp is an upper limit.
But if you have a good tune, the car can be pretty reliable at that power level. If you dial it back to low 300's (like 320 - 330 whp) then your chances of reliability are increased too.
I hope that helps, and thanks for watching!
@@FlatironsTuning okay thanks for your response. Say at 330 hp, what kind of life span are we talking provided the car has a good tune and is a street driven car driven only 2-3 times a week but the power would be used regularly. Thanks for your helpful comments.
Does this info also apply to ej205 engines?
as far as what maximum power a stock block (ej205) will hold up to.
Thanks for your question. Roughly speaking, I would say so. Though on a 2.0 liter engine it has a much different driveability at even 300 whp compared to the 2.5 liter engines.
Most of the time, once you get close to 300 whp on the 2.0 liter engine, the compromises needed to push further just don't fit for most people.
Hope that helps and Stay Tuned!
@@FlatironsTuning thank you for the reply! :)
i have a bugeye wrx, still on its factory motor. possibly looking 300hp, 320 max. what would you recommend be the best upgrades to get it to run the best for that power level? already got a mishimoto front mount + their short ram intake, not yet on the car as I don't have the money for the tune yet. umpire uel catless headers/up pipe (same story as fmic). and have been looking at things like better fuel pump, possibly something with a flow rate of 355lph (looking e85 compatible maybe as well) , bigger injectors and swap the tdo4 with a td05. the goal is the have mods be able handle more than what I want out of it to hopefully not have things so over worked if i do a spirited drive.
Thanks for your question. On the 2.0 liter engine, getting to 300 whp will require a bigger turbo (I'd say a TD05 20G at a minimum), and the result is typically a significant loss of usable power band. And If you are on a higher mileage engine, you may not want to stress that block that much.
I'd say that one of the best turbos for the 2.0 is a 16G, which should get you around 250 whp with a good tune. That makes the car a lot more fun, and it can still be reliable with a good tune.
Hope that helps, and thanks for watching!
@@FlatironsTuning awesome!! cheers for that. yeh not looking for crazy numbers. just looking to wake it up a little more and run more "efficiently" with less air flow restrictions and better cooling. would you think a 3 port boost controller/solenoid would be worth the investment as well? i've heard they help alot when you get a tune done to have more predictable and consistent boost levels
@@sebsshenanigans They can, but it definitely comes down to the turbo itself much more than the controller. But if you are getting a tune done, it is not a bad idea.
In a pinch, get one, and set it aside so you have it if you need it. Start with the stock solenoid and see if that will get the job done.
So what's your opinion and guideline on forged pistons like the eja207 from the factory
Thanks for your question. We haven't worked with enough of those engines to give you a solid answer I'm afraid. A lot of that would come down to what the piston to wall tolerance of the factory pistons was. They would definitely be able to handle more power than a block that came with cast pistons.
But if the PTW tolerance is tight to keep noise and wear to a minimum, that may be an issue above a certain point.
Hope that helps and Stay Tuned!
There not a true forged piston the only true frohed piston came in the Japan spec liberty rs
Is it advisable to swap out the JDM ej207 for an ej25 /255/257? I understand that the lining in ej25 is much thinner and prone to crack.
That is a hard question. I'd say that if your EJ207 is in good working order, there is not necessarily any need to go in and replace it. The EJ25 cylinders are a bit smaller than the EJ207 (especially compared to the thick wall EJ207 from the newer blocks), but they are not a limiting factor below about 550 whp.
Generally speaking, the decision about what displacement block would be best for you often comes down to power goal and desired power band.
I hope that helps, and Stay Tuned!
@@FlatironsTuning Appreciate the reply. Thank you!
@@FlatironsTuning am actually planning for a forged daily drive build. Minimal lag with some serious kick to the back upon full boost.
Was contemplating whether to go for a full 2.0 forged, 2.1 stroker or a 2.5 forged.
As per the above, my major concern in 2.5 build is the liner crack issue.
2.1 gonna be an issue to me in sourcing for the offset wrist pin piston.
2.0 straightforward build but bored?
Aiming at 400-450whp. Day dreaming of a flat 300-400wtq curve (wondering is it possible?)
Yet to decide on turbo.
If I'm looking to do a hybrid build using wrx heads and je pistons would you recommend installing the pistons on an new oem sti short block or at that point should I go with something like iags closed deck case halves and new rods etc? Only looking for around 375 hp.
If that is your power goal, you are just past the point where stock pistons would be at there limit, requiring forged pistons. You could certainly put them into a new OEM block, or build a new OEM case. You don't need a closed deck block. That is only needed if you are looking to push past 550 whp or so. You would not get any benefit for it at your power goal, and you would be adding a significant amount of cost to your engine build.
I hope that helps, and good luck with your build!
FlatironsTuning Thank you, for that 350-375 hp range would you always recommend starting with a new oem shortblock or is rebuilding a spun bearing or similar 257 okay to do for that hp? Not really looking for insane reliability because it's not going to be daily driven at all more for just autox and track events.
Well, the first step with any used block is to have a quality machine shop inspect it. If it is good, but needs to be over bored, I'd recommend not going to more than 99.75mm. you really want as much material in the cylinders as possible. 100mm is okay for moderate builds, but not ideal. For bigger power (450 whp+), starting with a new case is a better bet.
But overall, making sure that there are no issued with the block is critical before you start machining it.
Im building an ej205 power level is 300whp with stock 07 sti turbo (vf43). Im planning to go forged rods/ piston, stock crank, and stock heads. I need opinions.
Forged is overkill for those goals. Might as well go bigger with the turbo, or keep stock shortblock. Regardless, be sure to upgrade to STi / 06+ WRX oil pan, or an aftermarket pan
What's the power limit of the ej205
Thanks for your question. That is a slightly hard question to answer. It isn't as easy to get an EJ205 above 300 whp with a good usable power-band, so not as many people have done that so there is less information out there about it.
I think that I'd say that 300 whp can definitely be reliable on an EJ205 engine, but getting to that power level and still having a good powerband is the hard part.
You can certainly do it with a 20G turbo, but on the 2.0 liter, you end up with minimal power below about 3,500 rpm.
I hope that helps and Stay Tuned!
@@FlatironsTuning yea I'm shooting for 275whp
My favorite turbo for the EJ205 is something like an Evo-3 16G or Blouch's 16G XT-R. That will give you good power from 3,800 rpm on, and will pull to red-line. You should be able to make between 240 whp and 260 whp on that as well.
Hope that helps!
Any idea on short block recommendations when my OEM engine goes. Right now it's just stage 2 mods but when it goes I'd like to get equal lengths headers, and a cobb20g turbo. OEM block with safe tune or IAG stage 2 block?
Thanks for your question. If you are looking at a 20G turbo, that falls to the top of the range that the stock block can support. If you don't plan on trying to push past 350 whp, then I'd say that would make sense for your build.
If you want to have the option to go for more power, then the IAG block might make more sense, but you would have to make sure that you will be building to that power level in the reasonable life-span of the engine.
I hope that helps, and thanks for watching!
Ever thought about making videos on the new fa wrx?
Of course! Unfortunately we just don't have one that we can do testing on, etc. at the moment. I'm sure that we will find one at some point :-)
I just want catback & accessport te37 I'm good for my 2013 wrx I daily i baby my car
Can this guy build my engine please
Thanks for the vote of confidence, but engine building is not in my skill-set yet. If you need an engine built, we can point you to some experts that can take care of you ;-)
Thanks for watching and Stay Tuned!