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I tell everyone thinking about buying a wrx, treat it like it’s a living thing and it’ll live a long, strong life.

Reaction to the powerslide was a bit slow. Came out unscathed though, that’s what matters 👍.

What bov you running?

Good topic and good video.

I have a 350hp ej207 STi GDB JDM I want to build it for around 500hp lol But to be honest, its just of curiosity. Truly, I dont think you need more than 300-320hp for a fun ride with STI. More hp is just only for 100-200km\h. I mean, for that launch guys may be for 0-100, but its not really that fun. For me its the most fun just on some kind of touge with great nature around it, or just doing some some of 200+km\h on a decent highway. Well, and snow fun in the city.

I love this video and love your car! My '14 GR WRX is right at 300whp with a 2" lift coilover kit just to bring it to a comfortable height to get in and out of for a daily (also dedicated dog car). I also have a '23 VB WRX at 340whp which feels just right. But that being said, my '20 VA STI has 600whp and I absolutely LOVE the power. I knew what I was getting into and I keep up with the maintenance and upkeep on all 3 cars. I do warn my Subi friends about adding power, but I also endorse the decision, so I'm a bad influence lol.

Also, please do an install video anyways❤😂

I cannot wait to see the results of this. The results after your tune is updated will determine whether or not I go to single scroll/ewg or not.

damn they got even more expensive I think mine was 350 back in 2019. that crank pully tool doesnt work for the fluidampr. they one now but the regular one wont work none of the holes line up

sounds like you scraped the hell out of underneath

how much power you got now?

love the 2005 sti interior

PRE upgrade for the Subaru WRX and STI IHI turbos is based on the modern Garrett G25-550 turbo. BACKSTORY OF GARRETT: Garrett started offering ball-bearing turbos for production vehicles around 30 years ago in the early 1990’s and one of the cars using it was a JDM 1994+ S14 Nissan Silvia. The S14 used a ball-bearing Garrett T28 variant which is basically a GT2560R as called by the more modern Garrett nomenclature. Since then, Garrett went from the GT-series turbos (GT28, GT30, GT35, etc.) to the GTX-series with the GTX28, GTX30, GTX35 turbos. The only difference was a more efficient billet compressor wheel which was able to flow more air as measured in pounds per minute. After the GTX Gen1, came the GTX Gen2 turbos which had an even more efficient compressor wheel which typically can flow 10% more than the GTX Gen1 turbos. The turbines stayed the same for GT, GTX Gen 1, and GTX Gen 2. It’s all great at this point, but it became the end of the line for the GTX turbos. No matter how efficient the compressor wheel was at supplying air, you also need to get it out of the turbo and you need to get it out efficiently. This is the key to all this. The 25-year old Garrett turbine blade rotor technology worked great for two-plus decades, but has become the restriction. Exhaust restriction will increase exhaust back pressure, commonly known as EMAP (exhaust manifold absolute pressure) or EBP (exhaust back pressure), increase EGT (exhaust gas temperature), and can even lead to cylinder misfires and knock. Garrett did a complete redesign of their turbos and called them the new G-series. The GTX28 has been replaced by the G25, the GTX30 has been replaced by the G30, and the GTX35 has been replaced by the G35. There are a few larger GTX->G turbos that follow this nomenclature evolution as well. G-series compressor wheel design has been greatly improved even compared to the GTX Gen2 turbos, but most importantly, the turbine blade rotor design has been completely changed. The extra mass air flow that can be supplied by the comp wheel, can more-efficiently exit the turbine with less back-pressure. This combination of a highly-efficient compressor wheel is matched by a highly-efficient turbine for a 'balance-flow turbo'. An inefficient, old-tech, turbine cannot get the extra exhaust volume out and creates excessive exhaust back pressure (EBP), higher EGTs, and even additional knock will occur. Most common solution to lowering the exhaust back pressure is a larger turbine rotor (larger inducer and exducer) or an archaic clipping of the turbine exducer blades on the stock turbine. A larger turbine rotor will usually help reduce back-pressure and EGT, but usually at the expense of extra weight, higher moment of inertia, and more lag. Clipping turbine blades means you literally set up the shaft in the lathe or a surface grinder and machine off the tips of the turbine exducer blades to reduce their area, open up the area between the blades, and allow the exhaust gasses to get out of the turbo with less flow restriction. Reduction of blade area can also cause added lag. PRE TURBO UPGRADE HISTORY DEVELOPMENT I started rebuilding Subaru IHI turbos in 2010 and did my first upgrade on a VF39 back in 2014. The 11-blade compressor wheel you see most IHI turbo rebuilders use is based on the Garrett GTX2860R Gen1 and I worked with a company back in 2014 to develop it. This was a drop-in billet compressor wheel which required no compressor housing machining or modification and flowed 10% more than a stock IHI and typically picked up 30whp. Where a stock STI IHI turbo made +/-300whp on a Dynojet on pump gas, this upgrade made +/-330whp, while having same spool characteristics and better top end. The compressor wheel costs $100 and while 'already in there' for a turbo rebuild, makes perfect sense as the HP per dollar can't be beat and there is no other part you can bolt onto your car that will make 30whp for $100, PERIOD! After maxing out the capabilities of the drop-in comp wheel, I started machining compressor housings and fitting slightly larger comp wheels with great success. Eventually, you can’t go bigger than a 20G compressor wheel in stock housing so you have to start designing more efficient parts. The stock turbine shaft becomes a flow restriction with the 20G-sized compressor wheel anyway. Going back to the whole ‘crapping out what you take in’ theory. This is how the ‘G25 turbine blade rotor design on an IHI shaft’ came about. There are ‘high flow’ and larger turbines available online for the IHI, but all they literally do is keep the same blade profile as stock and remove one or two blades to increase volume between the blades and reduce back-pressure. This is nothing innovative compared to what Garrett did when they designed the G-series line of turbos. IHI has used the same turbine shaft on Subaru-production cars since late 90’s when the Impreza 22B came with a VF22 turbo. This turbine technology was great at one time, but now, can be considered 'ancient' and needs modernization. The goal of my upgrade project was to have a new comp wheel and turbine to work as a matched set rather than a stock turbine with high-flowing, bigger compressor wheels. PRE G25-500 UPGRADE FOR THE IHI TURBOS The Garrett G25-550 compressor wheel and turbine rotor sizes is very close in physical size to what’s in the stock Subaru WRX/STI IHI turbos. All these IHI turbos use the same cartridge with the same compressor wheel and turbine shaft dimensions and aero profiles. My solution is a custom hybrid turbine shaft and a custom compressor wheel based on the Garrett G25-550 turbo. The dimensions of the G25-550 compressor wheel had to be manipulated to make it fit the stock IHI compressor housing and be as close to original form as possible. Compressor wheel development went in the similar footsteps of the GTX->IHI from 2014. The G25-550 comp wheel is very similar in size to the IHI. Making minimal changes to the G25-550 allows it to fit the stock IHI compressor housing without modification. Since my product is not related to the Garrett corporation, I cannot use their G25-550 name, and don't need a 'cease and desist' for violation their likeness. Thus, the name of my upgrade is G25-500. The turbine shaft is a hybrid design using the blade rotor from the Garrett G25, but made with the IHI journal bearing shaft dimension and the blades are profiled to fit the stock turbine housings without any modification or machining required. The hybrid turbine shaft project was a fairly large financial investment, order of 100 pieces, and a 6 months manufacturing lead time. The first G25 turbine test ran on the dyno in October 2020 and by August 2021, I ran through all 100 turbine shafts from the original batch. After that, I had a second batch of 200 pieces of the G25 hybrid turbine shafts made. Attached is a picture of the stock IHI turbine shaft and my G25 hybrid turbine shaft. Blade shape is completely different and that’s what gives it the efficiency to match to high-flow compressor wheels. The compressor wheel and turbine shaft are both machined to fit the stock compressor and turbine housings without any modifications. For the DIY customer: buy the parts, drop them in, and go for a tune or buy a complete CHRA and swap it into your compressor and turbine housings. PERFORMANCE RESULTS AND COMPARISON TO STOCK A stock STI from factory is rated at 300hp at the crank. On a Mustang dyno, a stock STI on pump gas makes right around 220-225whp. On a Dynojet, which reads 10% higher than a Mustang dyno, a stock STI makes right around 250whp. An FBO STI on pump gas on a Mustang dyno makes right around 270-280whp. That’s right around 300-310whp on a Dynojet. An FBO STI on ethanol on a Mustang dyno makes right around 300-310whp. That’s right around 340-350whp on a Dynojet My G25-500 upgrade consistently makes 340-360whp on a Mustang dyno on pump gas. The lowest I have seen was 338whp and that was a 2019 STI at 19psi on pump with stock TMIC, stock turbo inlet pipe, and 100% stock header/up-pipe. Just basically my upgraded VF48, AEM340 fuel pump, ID1050x injectors, and a tune. The highest I have seen was 362whp at 20psi on pump gas on a 2012 WRX with a new OEM RA shortblock, stock D25 heads, HKS header, no-name up-pipe, full exhaust, and Perrin FMIC kit. On e85, my G25-500 upgrade consistently makes 390-400whp on a Mustang dyno. Lowest I have seen was 389whp on a 2006 STI with a new RA shortblock, stock heads, 100% stock header/up-pipe, stock TMIC, and turbo-back exhaust. Due to the restrictive stock header, it took 23psi to make that power. The highest I have seen so far was that same 2012 WRX that made 362whp on pump. That car made 404whp and 421 lb-ft on e50 at just 20psi while still being internally gated AND using an OEM wastegate actuator. I have a few people using my G25-500 upgrade on track day cars with great success and this summer, my upgrade was allowed to be used in SCCA Rallycross.

Ive been talking to PRE a little bit. Kind of torn. I have a Dom 1.5 in hand right now, and am trying to decide which way to go. I have 3 options. Run the dom 1.5 as is, send my stock turbo to him for the g25 combo, or send the Dom to him for a g series upgrade that he hasnt tested yet. So tough to decide what to do! I really just want ~375whp on pump.

What kind of dyno are you using? It's just the compressor wheel swap?

I loved my twin scroll vf37 ej20x. Made 380 hp and 320 torque on e85. I now have a 2.5l sti with a large old garrett and the driving experience is different. I am slow as all hell until i hit 3500 - 4000. Made 360 on 91 and it feels arguably faster because of the crazy jolt of power istead of linear power band. Small twin was better driving experience but bigger single on 2.5 is more fun :)

What turbo should i buy for this. I am currently running vf39. Im going to build a 2.1 stroker with 4032 piston, forged rods, springs, valves, shimless buckets. Just trying to build a oem+ Ej205

I have a 03 wrx on flex and im running 22psi all the way to redline. Engine is ej205. Its been 15k since i tuned my car and its been solid. Now i want more power 😂. But going to keep as is for longevity

Very interesting. Keep us posted on your results. I have a Ver 8 motor and VF36 that might need this.

Well Well Well...

Great Video. Side note Fluidampr has something no other damper has which is called a rotating weight. So when the engine is running the crank feels only 2/3 of the total damper weight due to the technology inside the inertia ring will be suspended in air while the engine is running.... Physics are cool !!!!!!!

Never accelerate going in a turn only once you leaving out

What’s your fan and rad setup for your swap? My gd rad sits wayyyy too close.

Ask for the Doc/Devin he is a buddy of mine. I have a 93’ almost exact thing just white w/ blue interior.

youtube.com/@superchargedpathfinder?si=VFWabUAVVqcmXcfJ

What are your wheel size.

I'm getting a new car 😅 No I'm not selling my hawkeye. I enjoy it to much.

Any options you recommend for the Lightweight battery? For the bumper beams, Oswald Performance sell an even lighter aluminum beam for front and rear. They also have a replacement subframe brace kit which is lighter than oem. Here are some things I've done to my 02 Impreza for weight reduction: - all floor mats removed - spare wheel, jack, and tools, literally everything from the trunk removed. - when on track, remove rear seats (takes less than a minute to remove and refit these, its ridiculous). other things to consider: - whiteline sell lightweight control arms. could help reduce unsprung weight - lightweight lug nuts

great vid man sick car

I want a GC8 so bad now thanks to you lol

Def gotta show the carbon fiber on the wing

Why would you delete ABS????

Had you been driving with the brake booster unhooked for a while, or just the abs disconnected?

how much power?

Have you ever heard of reoccurring issues with clutch master cylinders going out? Have gone through 3 master cylinders in 2 years in my 2011 wrx.. Its getting old lol

People do buy these cars because they can't afford G80s but I disagree with the mentality. What other cars makes power, has a robust 6 speed manual, and is AWD? Not to mention sounds this good and has an amazing aftermarket support. The communitys been ruined by kids who buy used ones (can't really afford them if you're talking about ownership, maintenance, and modding) and throw a buncha random parts on them. This car offers a driving experience that not even G80s will. And you can make the most of it, meaning add power to it safely. Yes you should definitely upgrade everything else, tires suspension etc. But I will go as far as to say that since there's no cars like these, you should have the car payment, religious maintenance, +20k in mods to say you can actually afford it. And it will be one of the most amazing driving experiences. The more you put into it the more rewarding it will be because again, no other car has the same formula

What interior do you have on (what year and car)

Sorry man, this video is just wrong. I get the angle you're coming at this from though because typically the type of person that buys this car and comes to TH-cam for advice is a young kid, 18-25 that doesn't have much experience on cars but always wanted an STI and now wants to get into modding it. THAT demographic cannot make this car fast, fun, and do it in a budget friendly way. An adult that can do their own research, do their own maintenance, learn for themselves, can do anything they want with the Impreza platform with enough time and money. You'd be hard pressed to find a car with more aftermarket support and experience in the world besides maybe the Ford Mustang. All it takes is being willing to read the old NASIOC forum, read the oem service manual, and then take modding one step at a time while doing all the work yourself so you can learn. Keep the car stock for awhile before you do anything. I bought my 06 WRX in 2014 from a friend. It was already heavily modded and unreliable but it's the car I wanted my whole life so I committed to keeping it and fixing everything myself. At the time I wasn't even confident in doing my own oil changes. 10 years later and the car is completely different. Makes 650 WHP and is more reliable now than the first 4 years I owned the car when it was basically stock. That's because I took my time to build it right, do maintenance on time or early, and don't beat the shit out of it everyday for no reason. I treat the car with the respect it deserves. I also opened up my wallet and emptied it into the engine bay for years collecting only quality parts and then installing everything together, the right way. No shortcuts, no garbage parts. It's got a built shortblock and heads, completely disassembled, clearanced, reassembled by me. Full STI driveline swapped with the newer 6 piston brembos, transmission rebuild by me, full suspension overhauled by me, custom engine wiring by me, custom turbo kit, ect. All I had was the NASIOC forums, the oem service manual, my 2 hands, and time. If you want to own one of these cars and really build it, you need to be patient and ready to learn a lot. There's literally no limit.

Some notes: Subarus are still best in class in rally, as far as I'm concerned. Tons and tons of NA4WD old Subarus competing and winning rallies across north america. Power to weight IS everything, and when you consider the stunning weight of a Hellcat, somewhere in the realm of 4500lbs, taking weight out of a GC or a GD or even a GR, VA, or VB stats cclosing the gap when paired with small boosts in power. Also, w/r/t 2J swaps: you bought THE available boxer engine, all wheel drive platform, and your first instinct is to take that element away from it, why? 2Js go in so much other stuff, so much more easily than they go in a GC or GD. Whats frustrating is that there are also folks that put all this money into power into their Subarus, and then think that they can take their 400HP+ STi and put it on a rally stage and compete, becuase they've arleady spent all the money; you cant. Vermont Sports Car builds championship winning WRXs, and they're probably putting just barely over 300hp out of the crank or at the wheels, I cant remember. They get those cars weighing as little as possible, they take weight out of some areas and put it in others for better maneuverability, etc etc. Horsepower does not win rallies, the driver does.

Laughs in 800whp sti.

You're right.. That's why we are going for 1000hp baby!

I've been there with my Impreza coupe WRX swap, but only in the parking lot. I don't have the balls to take it on track. Looks like a blast!

This isn't snap oversteer this is just failing to counter steer

The way the 240i took off on the at the beginning of the straight is impressive. Big B58 laying down the power.

😅 ouch this is probably not going to go over to well. People don't usually tie the VA VB together VB being all kinds of different. Nevertheless each their own. Personally I think the VA is the perfect balance. A modern-ish all around performance car. It looks modern plenty of parts availability. Is it heavy Sure is but that's only one part of it. Is it expensive maybe it depends. Where you want to allocate your resources to. I tended to drive a dog s*** reliable efficient daily. Also something I don't care about that I can park in a Walmart parking lot.😅 I couldn't see myself wasting money on an Audi sq5. That's a nice long Long block.

Need some help with your hand placement. Otherwise nice lap

Thank God you made this video. That is why I will never power mod my 2020 WRX/STI. My Bluebaru will remain stock forever. The STI is a legend. I get all types of cars always trying to race me to and from work out here in Ca. 😊 A great video brother. Subies forever.

Gonna make my subie push 1500hp

This is why you never accelerate in the corners

Hell yeah!