The reason for less blades in the JDM water pump is to reduce cavitation of the water at higher rpm, the R32 GTR also did this on the RB26DETT N1 engine, which also has less blades.
Great video. I’m really glad you gave some hydrologist insight on the water pump blades. As someone who knows basically nothing about fluid dynamics, I would have assumed the JDM pump with bigger blades and a bigger gap would have moved more water
That water pump difference is strange. The angle on the back of the blades is different too. The EJ207 revs MUCH higher than the EJ205 so I would imagine part of the reason for the difference is optimizing performance and minimizing cavitation at very high RPM.
The answer is much simpler than that, it is simply due to external temperature. Japan simply does not exceed 30 degrees celsius where as places like the US and Australia can exceed 40 degrees celsius + requiring a better cooling system to offset that difference.
Man sometimes I get overwhelmed, then I find lots of info with great ppl like you sharing their Subaru knowledge and I’m thankful for that. Now that I’m getting the engine out, I don’t want to rush, set a goal a day to do things right. Appreciate your work & thanks.
Hey, I own both v7 ej207 and v8 ej207 and can confirm they both use the same crank pulley even though one has forged pistons and the other has hypereutectic pistons. Just thought to share that with you. Love the content, keep up the great work man!
Ej207 ftw You are going to love the 207, such a healthy poweband. AVCS gives a noticeable increase in torque down low. They really scream all the way to 8k without hesitation!
I really appreciate the in depth analysis. I'd like to add that the 6 blade STI water pump designed to slow the coolant flow to aid thermal exchange as well as to lower the resistance at higher revs.
It would be a lot of work, but you should totally add chapters for this video for each of the parts comparison. It will optimize it for search on Google as well as letting people find what they need in it.
Another awesome video Luke! Super informative! I love my ver8 ej207, a couple differences from the v7 ie twin scroll and i don't think forged internals on the v8. But man Your going to love that 207 these little guys rip! Glad your back man! Take care keep safe! 🍻
Just picked up a V9 207 that I'll be running with a V7 ecu in my blobeye. Had low compression, so I'm going to have the bottom end built. Hopefully I can get it running in the next few months!
Amazing video! I have always wondered about the differences. The forums never go into this kind of detail and I am a visual learner so seeing the differences first hand really helps!
@@SubaruONLY I had a question pop into my mind about avcs heads. Could you take the AVCS and sti cams off sti heads and use them on ej205 heads? Then wire-up the heads to a avcs equipped JDM ecu? Or is that not possible?
Interesting and possible. One thing I didn’t mention, was that the 205 was made in 2005 and the 207 was made in 2001. So maybe it was just an evolution of the pump design. Not 100% sure though.
The TD04-13T can get an inexpensive Saab -19T upgrade and will bring the flow about 2/3 the difference of the VF30. The 04 257 ecu should be able to run the 207 without a tune (of course it would run better with one). The desirable water pump is the solid face impeller because it has less cavitation. I believe the oil passages are quite a bit different as well.
@@tflo9543 You are correct since it is equipped with a VF30. I think several solutions may be possible; Use the USDM 257 ecu and convert to DBW and a merged harness Use the JDM 207 ecu and merge the harness, Run the 205 ecu and disable the AVCS, Or some other answer so he can run in CA.
Yes, running the USDM ECU with the 207 heads and shortblock, plus TGVs, but it can’t activate the AVCS - as you pointed out. But it’s running great on that US ECU.
Great video! Wish you would have had the exhaust ports clean and spent more time comparing them. Almost looked like the usdm had larger final diameter exhaust ports vs the “better” jdm head…? I will be porting my USDM heads and am researching…
i have an Aussie delivered 2003 GD wrx that came with a 205. I then swapped it with a 207 (we got the same motors as Japan) first came in the 99 gc sti. The reason for the water pump change is difference in driving behaviour/usage
2.0L Subaru's cylinder heads side walls are thicker than 2.5L or H6 3.0L It means it would take more boost! If you want to make heads more durable it involves CNC drilling between cylinder head and water jacket and inserting metal rods
Idk the technical reason for it but alot of the older waterpumps on US engines were like the one off the 207 and the newer replacement pumps had all changed to the newer style like the one on the 205 ... I worked at a Subaru dealership for a long time and I remember reading a tech note about that change..maybe 01 or 02?? Cant remember for sure
Wow, fantastic video. Thank you very much! I’m just importing a 2008 STI hatch from Japan. It has the EJ207 v10 I believe. Does anyone know where I can find the factory service manual it?
I think I might need to use a combination of manuals. The USDM for the hatch display a lot of information relevant to the car but the engine information is for the EJ257. From my research service manuals for the Australian 99-07 wrx Sti should have info on the EJ207 engine maintenance? This would obviously be earlier revisions than then the v10?
Only S series and spec RA / spec C ej207 have factory thermostatic external oil cooler... Normal jdm sti ej207 use water-oil cooler unit like the rest of turbo ej
I was told by my mechanic that there wasn't a truly forged factory piston wrx, there was in the legacy turbo jdm they say the 207 has forged pistons but it doesn't
I like how I can get too ahead of myself bc I barely know how to diagnose my car problems and yet I’m here learning about EJ engines for a future swap🤣
Need some help or atleast pointers on a swap.. jdm ej205 in to a 2002 rs 5 speed shell , will it just drop in? And i am geting i wire harness merger to keep de avch , what should i know to make this work?
Gonna need serval items swapped over from the US ver to the JDM to make it all work - check out iWire’s YT content for this exact swap and all the details (or just give them a call) - they break it all down perfectly. Cheers and good luck!!! 👍
Okay here’s my question my 2011 Sti spun a rod so I decided to get a JDM ej20 it has dual avcs z20 heads ..the first ej20 jumped timing due to error but the block is fine my original Subaru had dual avcs w25 heads on a ej257 block..could I build the JDM motor and everything work properly where it’s dual avcs I swapped the cam sensors to usdm I basically now have two ej20 blocks and would like to build them instead of sell them and deal with a headache I know it’s not the same size where it’s a 2.0 but I was gonna have it closed decked and honed for new pistons and put the stock heads back on to make around 400-450whp with supporting parts
Excellent video. Wish this came out 10yrs ago in the engine swap heyday and a lot of misinformation were everywhere.... if you get q chance to verify the jdm ej205 HT20 HEADS that would be cool
So I just grabbed a EJ253 AVLS for 2.5i. I want to use the cleaner manifold. Other than swapping sensors if clips don’t match and both use electric EGR on manifold Can I just not use the whole long block or just block??
@@SubaruONLY thanks bro. Interesting how much actually matches up. Other than A/C harness clip. They all share the male/female clips. Car runs excellent
What ive seen having seen some of the jdm parts when they were still pretty new and in Japan on the car the red wrinkled finish on the jdm engines start out as a bright colored paint but they have a tendency to darken over time and I was under the impression that the OEM paint was just a darker color than the paint that I was able to find here in the states...but in actuality they start out as a very VERY similar color.... Just a useless little fact I was able to find out lol.... I end up powder coating as much as I can wrinkle black now days lol
@@SubaruONLY I have a jdm v8 and my buddy have the jdm version 7, the version 8 have the better heads and twinscroll setup but the 7 was bless the all the forge internals
I hope you got the message about WHEEL TECHNIQUES in Santa Clara, CA the other day. LMK. Talk to JOHN. I have known him for over 30 years. He does great work. Good job Luke. Lots of awesome details I never knew about those engines. God willing, I will do some sort of Subi racer someday. I have the ability, but cashflow and time won't allow right now. Just trying to keep my head above the water right now.
Thank you! Yes, I did see that - will def reach out to John and I’ll mention you gave the recommendation!!! Feel ya on staying above water, been there more often than I would prefer, but that’s life, gotta do what you can, when you can. Cheers and thanks again for the recommendation!!!
Japan is generally pretty cold, therefore a "less efficient water pump" will suffice, hotter or broader range temperature ranges require better cooling capabilities. Much the same as how older model european cars had terrible A/C where im from in Australia, they failed to address this issue before importation and the systems they used were not effecient enough for our climate!
I'm a little sure it's more correctly a 255 vs a 205. not to be confused as a negative dis. just wanna keep it straight. great stuff. please look for my email I sent. hope to talk to u soon my friend.
Sorry, I can't listen to you repeat yourself over and over. Honestly, the video could have been half the length. Seriously, go back and count hoe many times you say the same thing twice. Couldn't get through the whole video.
This channel is so underrated! So much info and so easy to follow along when describing individual components!
Thank you!!!
He’s Humble and will be around longer because of it. Versus mainstream
The reason for less blades in the JDM water pump is to reduce cavitation of the water at higher rpm, the R32 GTR also did this on the RB26DETT N1 engine, which also has less blades.
Yep and prevented foaming
Great video. I’m really glad you gave some hydrologist insight on the water pump blades. As someone who knows basically nothing about fluid dynamics, I would have assumed the JDM pump with bigger blades and a bigger gap would have moved more water
Actually not neccessarily moves more water...
But its more about reducing pump cavitation at high rpm (ej207 revs to over 8k rpm)
That water pump difference is strange. The angle on the back of the blades is different too. The EJ207 revs MUCH higher than the EJ205 so I would imagine part of the reason for the difference is optimizing performance and minimizing cavitation at very high RPM.
Ya I believe you’re correct in the difference reasoning
The answer is much simpler than that, it is simply due to external temperature. Japan simply does not exceed 30 degrees celsius where as places like the US and Australia can exceed 40 degrees celsius + requiring a better cooling system to offset that difference.
Minimizing cavitation is in my opinion correct but temperature plays a large role in cavitation to begin with 😊
I love these super tech talk videos, thanks for the comparison it actually helped a lot with determining my build!
Man sometimes I get overwhelmed, then I find lots of info with great ppl like you sharing their Subaru knowledge and I’m thankful for that.
Now that I’m getting the engine out, I don’t want to rush, set a goal a day to do things right.
Appreciate your work & thanks.
Thanks for the kind words buddy - much appreciated. Good luck 👍
🙏🏼🙏🏼
Hey, I own both v7 ej207 and v8 ej207 and can confirm they both use the same crank pulley even though one has forged pistons and the other has hypereutectic pistons. Just thought to share that with you. Love the content, keep up the great work man!
Awesome man. Thanks for the first-hand info!!! Nothing better!!! 👊
Nice - thanks for sharing!!!
Any other differences between the 2?
Excellent video! This is the most thorough comparison I've found of the EJ205 vs EJ207. As a relative Subi noob, this was extremely enlightening.
Ej207 ftw
You are going to love the 207, such a healthy poweband. AVCS gives a noticeable increase in torque down low. They really scream all the way to 8k without hesitation!
The avcs is Only on the JDM version, I believe. Euro doesn't have it and the usdm i'm not sure.
@@PedroFTeixeira
Only jdm, we never got an ej20 w/ AVCS in the states.
@@tflo9543 how about in narrowbody hatch 08 wrx?
Still no ej20 avcs?
@@AmirPomen NOPE
Yep, exactly 👆👆👆
Nice video Luke. You’ve been missing for some time now. Glad your back!
Thank you buddy!!!
I really appreciate the in depth analysis. I'd like to add that the 6 blade STI water pump designed to slow the coolant flow to aid thermal exchange as well as to lower the resistance at higher revs.
So I made a good choice! Just dropped a 207 into my bugeye wrx. Mating it with a vf39 STI injectors and STI intercooler
It would be a lot of work, but you should totally add chapters for this video for each of the parts comparison. It will optimize it for search on Google as well as letting people find what they need in it.
I totally need to man. Sorry for the late reply!!!
Another awesome video Luke! Super informative! I love my ver8 ej207, a couple differences from the v7 ie twin scroll and i don't think forged internals on the v8. But man Your going to love that 207 these little guys rip! Glad your back man! Take care keep safe! 🍻
Just picked up a V9 207 that I'll be running with a V7 ecu in my blobeye. Had low compression, so I'm going to have the bottom end built. Hopefully I can get it running in the next few months!
Great video, easy to understand and packed full of info, great for Subaru noobs!
good show and detail = i have just brought a ej207 RA type C short block and will go into my sf GT forester !
Amazing video! I have always wondered about the differences. The forums never go into this kind of detail and I am a visual learner so seeing the differences first hand really helps!
Glad it helped. Sure hoped it would for some people.
@@SubaruONLY I had a question pop into my mind about avcs heads. Could you take the AVCS and sti cams off sti heads and use them on ej205 heads? Then wire-up the heads to a avcs equipped JDM ecu? Or is that not possible?
Good informational video, thank you for taking the time to go over the difference between the two engines. Clearly that is a ver 7 ej207.
Another great video Luke. You're putting out some great content!
Keep it up!
thank you!!!
Great breakdown and explanation. Had to take a ton of set up
Great video! Keep up the great work on this awesome content.
Is it possible that since the 207 revs higher, the water pump is designed differently to avoid issues of flow at higher rpm?
Interesting and possible. One thing I didn’t mention, was that the 205 was made in 2005 and the 207 was made in 2001. So maybe it was just an evolution of the pump design. Not 100% sure though.
The TD04-13T can get an inexpensive Saab -19T upgrade and will bring the flow about 2/3 the difference of the VF30.
The 04 257 ecu should be able to run the 207 without a tune (of course it would run better with one).
The desirable water pump is the solid face impeller because it has less cavitation.
I believe the oil passages are quite a bit different as well.
Don't think you can run a 207 on a 257 ECU. One is throttle by cable other is by wire.
You can start and run on a usdm ej205 computer temporarily.
@@tflo9543 You are correct since it is equipped with a VF30. I think several solutions may be possible;
Use the USDM 257 ecu and convert to DBW and a merged harness
Use the JDM 207 ecu and merge the harness,
Run the 205 ecu and disable the AVCS,
Or some other answer so he can run in CA.
Love this comment man. Such great info - THANK YOU!!!
Actually, this ver7 207 is throttle by cable too. Same as the US 205.
Yes, running the USDM ECU with the 207 heads and shortblock, plus TGVs, but it can’t activate the AVCS - as you pointed out. But it’s running great on that US ECU.
This will be the "go-to" channel in the future ... nice😎
lol… thanks brother!!!
Great video! Wish you would have had the exhaust ports clean and spent more time comparing them. Almost looked like the usdm had larger final diameter exhaust ports vs the “better” jdm head…? I will be porting my USDM heads and am researching…
Mind opening. Thank you for the great explanations of all components.
You’re the best, man, love your videos
Thank you man - much appreciated. Sorry for the late reply.
Love your channel so much! Please keep your hard work!
Thank you! Means a lot. Lots more to come!
Great information, always look forward to these videos.
i have an Aussie delivered 2003 GD wrx that came with a 205. I then swapped it with a 207 (we got the same motors as Japan) first came in the 99 gc sti. The reason for the water pump change is difference in driving behaviour/usage
Interesting. Thank man!
The coolant lines on the throttle body is good for venting the system of air.
2.0L Subaru's cylinder heads side walls are thicker than 2.5L or H6 3.0L It means it would take more boost!
If you want to make heads more durable it involves CNC drilling between cylinder head and water jacket and inserting metal rods
👌👌👌
Hello. I have a forester xt 2007 manual. The engine is dead. Do you recommend rebuilding or getting a used low millage engine ?
Idk the technical reason for it but alot of the older waterpumps on US engines were like the one off the 207 and the newer replacement pumps had all changed to the newer style like the one on the 205 ... I worked at a Subaru dealership for a long time and I remember reading a tech note about that change..maybe 01 or 02?? Cant remember for sure
Nice. Thanks for sharing!!!
Wow, fantastic video. Thank you very much! I’m just importing a 2008 STI hatch from Japan. It has the EJ207 v10 I believe. Does anyone know where I can find the factory service manual it?
I think I might need to use a combination of manuals. The USDM for the hatch display a lot of information relevant to the car but the engine information is for the EJ257. From my research service manuals for the Australian 99-07 wrx Sti should have info on the EJ207 engine maintenance? This would obviously be earlier revisions than then the v10?
Is the turbo inlet bigger? Or just no taper? Tapered inducer looks bigger overall
BTW, came back to say, my ej207 has the oil cooler, so I'm not sure if maybe yours just didn't have it after being removed from its original car
Gotcha. 👌
@@SubaruONLY just curious on your thoughts there too 😁
My 207 def had the oil cooler too. I was just saying many used JDM engines don’t have oil coolers, I prob made that confusing - my bad.
Only S series and spec RA / spec C ej207 have factory thermostatic external oil cooler...
Normal jdm sti ej207 use water-oil cooler unit like the rest of turbo ej
is there a difference in size from left to right on the EJ20, EJ25 and the EJ205?
What about injector differences? Also did Subaru use the same injectors for GC8 as GDA?
I was told by my mechanic that there wasn't a truly forged factory piston wrx, there was in the legacy turbo jdm they say the 207 has forged pistons but it doesn't
Most useful. Thank you very much!
Brilliant. I have a jdm bugeye in the UK
I like how I can get too ahead of myself bc I barely know how to diagnose my car problems and yet I’m here learning about EJ engines for a future swap🤣
Cheers Luke 🙂
Great video thank you
Need some help or atleast pointers on a swap.. jdm ej205 in to a 2002 rs 5 speed shell , will it just drop in? And i am geting i wire harness merger to keep de avch , what should i know to make this work?
Gonna need serval items swapped over from the US ver to the JDM to make it all work - check out iWire’s YT content for this exact swap and all the details (or just give them a call) - they break it all down perfectly. Cheers and good luck!!! 👍
Maybe trying to prevent cavitation at 8200 rpm with the water pump?
Okay here’s my question my 2011 Sti spun a rod so I decided to get a JDM ej20 it has dual avcs z20 heads ..the first ej20 jumped timing due to error but the block is fine my original Subaru had dual avcs w25 heads on a ej257 block..could I build the JDM motor and everything work properly where it’s dual avcs I swapped the cam sensors to usdm I basically now have two ej20 blocks and would like to build them instead of sell them and deal with a headache I know it’s not the same size where it’s a 2.0 but I was gonna have it closed decked and honed for new pistons and put the stock heads back on to make around 400-450whp with supporting parts
My usdm 2006 wrx will need a new engine in year or two, should i swap the jdm 207 into it? What do you guys think
Excellent video. Wish this came out 10yrs ago in the engine swap heyday and a lot of misinformation were everywhere.... if you get q chance to verify the jdm ej205 HT20 HEADS that would be cool
Hey mate i have a ej204 would i be able to plus T or not a good idea?
I did a jdm ej205 on my 1999 Subaru Impreza rs do you know what could me wrong because it just keeps cranking but won’t start?
Did u swap the cam gears?Sprocket from the crank should be good.
Which would you think is better, and also easier to put in a 2006 wrx?
Hate to ask. Been looking for an EJ207 for months. Any ideas. I live in California. Thanks.
So I just grabbed a EJ253 AVLS for 2.5i.
I want to use the cleaner manifold. Other than swapping sensors if clips don’t match and both use electric EGR on manifold
Can I just not use the whole long block or just block??
Should be fine to swap it over… just need the sensors and same throttle type, as you mention.
@@SubaruONLY thanks bro. Interesting how much actually matches up. Other than A/C harness clip. They all share the male/female clips. Car runs excellent
👍
I wonder will ej205 spark plugs and coils fit ej207?
What ive seen having seen some of the jdm parts when they were still pretty new and in Japan on the car the red wrinkled finish on the jdm engines start out as a bright colored paint but they have a tendency to darken over time and I was under the impression that the OEM paint was just a darker color than the paint that I was able to find here in the states...but in actuality they start out as a very VERY similar color....
Just a useless little fact I was able to find out lol.... I end up powder coating as much as I can wrinkle black now days lol
Interesting!!! Thanks for sharing this info!!!
Would a 2002 to 2005 forester 2.5 sohc engine would fit on a 2007 forester?
Doesn’t the 207 also have oil squirters where the 205 doesn’t?
16:28 open deck block how much max hp can handle?
Dam I have a jdm ej205 i wanted to know the difference with the usdm ej 205.. nice vid
Sweet, glad it helped!!!!
Jus a little correction the v8 are the big port head not the v7
Hmm… I could be wrong, but thought JDM only ver7 models had the big ports. You might be right, I’ll have to look into this more. Thanks!!!
@@SubaruONLY I have a jdm v8 and my buddy have the jdm version 7, the version 8 have the better heads and twinscroll setup but the 7 was bless the all the forge internals
the only big port V7 is the spec C. the spec C dimensions are used moving forward into V8 being stock big port.
every spec C is used as the stock config for the next version.
the v8 also has the long runner intake manifold
Good information Luke, do you have to change the wiring loom if you change to an ej 207
no change needed unless you want to run avcs, and iWire makes a easy kit for like $160?
Yes, that’s a bit tricky for everything to work, I’ll make a video breaking this down soon too. Thanks man!!!
great video!
Thank you!!!
Can the ej207 parts and ej257 parts be interchangeable?
what do stock v8 ej207s dyno at? and crank rating?
I hope you got the message about WHEEL TECHNIQUES in Santa Clara, CA the other day. LMK. Talk to JOHN. I have known him for over 30 years. He does great work.
Good job Luke. Lots of awesome details I never knew about those engines. God willing, I will do some sort of Subi racer someday. I have the ability, but cashflow and time won't allow right now. Just trying to keep my head above the water right now.
Thank you! Yes, I did see that - will def reach out to John and I’ll mention you gave the recommendation!!! Feel ya on staying above water, been there more often than I would prefer, but that’s life, gotta do what you can, when you can. Cheers and thanks again for the recommendation!!!
had a subie when i was in highschool....i think its time again !!!
Nice 👍 Never to late to come back into the fold buddy. What you thinking about picking up?
@SubaruONLY blob eye or hatch STi.. I know I’ll find a great deal because I’m willing to catch flights for the best condition one lol
Nice 👍 good luck!!!
so which is best to use ? JDM or USDM ?
as in most power without Turbo.
Both about the same for NA. JDM stuff only better for boosted conduits really.
Throttle body Coolant Mod!!
Super helpful
I have a 207 2001 forester
That was awesome
Did the ej207 come with forged pistons ?
In 02 sti ej207 in japan
where did you source the 207? ebay?
Found it on CL. Crazy story that I’ll share in a video at some point.
BaderBuilds should start taking notes from this channel on how to present a well coherent content rather than a chaotic one.
Haha, thanks - love his channel. He’s the man!!!
Japan is generally pretty cold, therefore a "less efficient water pump" will suffice, hotter or broader range temperature ranges require better cooling capabilities. Much the same as how older model european cars had terrible A/C where im from in Australia, they failed to address this issue before importation and the systems they used were not effecient enough for our climate!
There's actually even a better water pump propeller that's a cast part and the props are covered.
Thanks man. And for the Fb post on this subject! 👊
Thanks
EGR pipe?
Sti valves are sodium filled compared to the 205
Best info!!!👍👍
Ahhh, glad you dig it man. More to come!!! 👍
do you have a email I could send you a question I have about my ej207
Yes, sure do!!! Send to:
SubaruONLYShop@gmail.com
👍👍👍
👍👍👍
I'm a little sure it's more correctly a 255 vs a 205. not to be confused as a negative dis. just wanna keep it straight. great stuff. please look for my email I sent. hope to talk to u soon my friend.
Def a ej207 - confirmed via multiple lines of evidence. But THANK YOU for the support and the comment. Cheers buddy!!! 👊
Sorry, I can't listen to you repeat yourself over and over. Honestly, the video could have been half the length.
Seriously, go back and count hoe many times you say the same thing twice.
Couldn't get through the whole video.