Probably not, to be honest. Feel like the OEM setup is fine for anything that remains totally OEM tune. Can’t hurt, but there’s always the chance something isn’t reconnected quite right, so there’s always a slight risk when doing any modification.
Interesting take on piston 4 failures. From what I've come across within the Subaru community, lean mixture in cylinder 4 stemming from OEM series fuel line system was to blame (you did touch on this). Limited cylinder 4 cooling does make sense too though. Thanks for the thorough cooling system break down.
Hey Luke I have a very important question regarding my 06 forester ej2.5 non turbo I watch alot of ur videos and I can say love it and interesting .. this video does this apply to non turbo ej2.5 too
+Manuel Berrueta Awesome - Thank you. That is what I'm trying to do - Provide value in every video, so people feel like they actually gained something or thought about things in a slightly different way. Anyways...THANK YOU! More to come!
Between parallel fuel and the reverse cooling mods If Subaru is so cool why don't they do these things from factory? Thanks for helping me realize Subaru has lots of room for improvement.
Came here from another vid of yours If you do a remake of this can you talk about pulling off the headers and looking at the exhaust valves. While back when I looked at mine all were the "rich white colour " but the last one on fuel rail
Is it possible to remove all the hard lines and only run the OEM fuel rails with parallel fuel lines? Or do you need to upgrade the fuel rails as well? If so can you do a tutorial on how you hookup the hoses to the OEM lines
This way you invert the order the cylinders get fuel. It should be after the split one line going to the front of the right fuel rail and the other to the rear of the left fuel rail (left and right as in you scheme).
SubaruONLY Honestly I have no idea if changing the firing order with respect to stock will make any difference. Many seem to be doing the way you did. But if you take a look at the Perrin fuel rails they are setup the way I described, which maintains the firing order unaltered.
+siliconfilm Hey - thanks for the follow-up. So I don't change the ignition firing order - I keep it 100% stock. For the fuel system...The side that the fuel enters the fuel rails doesn't really affect how or when the injectors distribute the fuel (unless we start getting really technical). All that matters is how much pressure drop you see across all fuel rail points and not putting too much heat into the fuel before it enters the rails. Too much pressure drop and you'll end up with inconsistent fuel delivery and too much heat transmitting into the fuel line could cause vapor lock (blocks flow of liquid fuel). Hope this answers at least part of your question. Cheers my friend!! 🤙🤙
SubaruONLY great so the firing order stays the same. One thing you can do to keep fuel cooler is running the fuel lines over the intake manifold. I guess if you use large aftermarket fuel rails and larger fuel lines you could also keep the design in series and the greater flow should fix the allegedly lean condition of cylinder #3.
Excellent content! Recently discovered a fuel leak under the intake manifold of my 05 sti. In the process of repairing the line, would it be wise to go with a paralleled set up? Would I need a tune to run this modification?
Hey man. No tune needed for switching to parallel fuel line setup. Is it needed, not likely for near stock STi. Will it hurt, not at all if installed correctly. Good luck!
@@SubaruONLY Do you have to run a fuel pressure regulator if you're running stock power? Would be nice to do this setup when fixing my fuel leak without having to spend money I don't have on a fuel pressure regulator.
Interesting you're using standard lines, can I ask why you chose that route and not braided? Personal choice maybe? See my videos for my 472bhp JDM TYPE R, parallel rails are next for me and trying to weigh up options 👍
+Aaron's Videos Thanks for dropping the question. And btw, your car sounds awesome - I will check it out. I went with stock lines cause I was staying with the stock rails and those rails have the smallest inner diameter/choke point at their inlets and outlet points for the entire fuel system. So, go bigger diameter braided would actually not have helped the flow of fuel in my case. HOWEVER, if I went to larger rails, YOU are 100% on target and larger ID fuel lines (braided or any high performance type - there's so many options out there now) would be the only way to go. If I stayed with stock lines at that point, I wouldn't be taking advantage of the new ID and associated fuel capacity of my new rails!
I'm interested in modifying my stock fuel lines on my 2003 wrx, everything is off the longblock for a jdm block swap anyways and I want to create a safer fueling system while I'm at it. Do you have any ideas for the fuel pressure regulator faceplate on the cylinder 1&3 factory fuel rail? I'm thinking of chopping it off and having the hole welded up. But if I could just tap it and use it as a return line so that both fuel rail return lines lead to the same FPR that would be great. I can send pictures of the concept I have in mind I would love to have your input. Love the channel, thanks a ton!
SubaruONLY Tomei actually makes a FPR adapter to a 1/8 npt thread. So I'm going to use 2 passenger side fuel rails with these adapters leading to my return lines.
@@SubaruONLY I’m glad to join your channel and have just bought myself some parts off of your Amazon Store. Would you like to consider making videos on how to make more power and torque in a non turbocharged ej motor? I know that it’s not the most cost effective way to make power but ( I love the na ej as it is playful and peppy, just not powerful) what can be done to a Sohc EJ22 engine?
@@SubaruONLY That’s works well for me, any recommendations on the type of supercharger and brand to best utilize for a fun street/ occasional track car?
+JackstandJohnny You are 100% correct about cylinder #4 being the most common failure location. This is also a highly debated question, here are my thoughts: (1) The fuel distribution is definitely one of the culprits but I think there are some other things at play here as well. (2) For example, the knock sensor is nearest to this location and I have read that Subaru tunes their ECUs to advance spark on this cylinder more than others to creep up on highest advance possible, then it uses the threshold for that cylinder as a proxy for max timing advance on all other cylinders. (3) I also think the fact that the cylinder is in the back of the engine plays a role as this causes more heat soak than the two front cylinders. I'm sure that's not all of the reasons but those seem like some big ones to me. Hope this helps or at least keeps the wheels turning...Thanks 👍👍
How did you take the stock fpr out of the system ? You must of used a dual input regulator for this to work or the first fuel rail would have no pressure ?
It helps keep the pressure even across all fuel injectors. This is because the pressure drop happens right after all the injectors, which helps act as a buffer to minor fluctuations.
Parallel is good regardless of the injector size. And, as the fuel flow requirements increase, parallel flow only helps more. So, in other words, can’t hurt at all!
+Mark Villanueva Actually, I would because I feel my evaluation of inner ID and factors that control things like turbulence is adequate to make a good judgement. The one think I can’t really assess is the quality of the material used - that’s the one risk, but I’ll just keep eye on wear and tear on the parts.
What year is it stock series? I know the 08-14 stis are parallel from factory. Dom has a whole video on it. Cant remember what all years and models it includes
Well... like so many parts, this is a part that is a little costly if you buy from reputable manufacturers - which I 100% do recommend doing. There are cheapo eBay ones out there but this part is something that can cause major engine damage if it fails or starts to become inconsistent - so stick with the high quality manufacturers. Here’s the ones I like: (1) AEM, (2) Radium, (3) Tomei, (4) Deatschworks, (5) Aeromotive, or (6) FuelLab. These are all legit and reliable options!!! 👊
+moog - I have but have not personally gone down this rabbit hole. From what I understand, it's basically the OEM fuel dampners that are impacting higher than stock fuel flow characteristics. This can create that stumble between 2000-3000 RPM - Super annoying! SOLUTION: Many have had good luck using the IAP or the COBB kit - I would try one of these. Thanks and good luck. Let us all know how it goes! 👍👍
I am trying to resolve a gr stumble. That's how I found your video. I have 1000cc injectors on factory rails and lines and I have a aeromotive fpr. I still have a stumble. I'm looking at new larger rails like iag plumbed in parralel. I think your mod may be a better fit for me.
I've been doing some reading and saw a thread on nasioc discussing why series is better than parallel for our engines. Not saying it's right or wrong, but since the point was that since none of the cylinders are firing injectors at the same time (or the overlap is negligible) there isn't much gain to be had by going parallel. They were also saying one of the reasons people have problems with the junky agency power rails is due to the fuel velocity being halved in each rail and somehow inducing vapor lock. BTW, just found out about your channel and subscribed. Keep up with the awesome content! interested to hear your thoughts... Ryan
+ryan lewis Thank you for checking out the channel and for taking a second to post a comment! Much appreciated! The whole discussion on 'Parallel vs Series' Fuel System is is a hotly debated topic for sure - It has been for many years in Subaru circles. I think there are probably compelling arguments for either position. As you get into the technical details, there is a lot happening here, as you touch on by mentioning the aftermarket rails and the impact to fuel flow velocity. One could probably write an essay on this question alone but I don't think anyone what's to see something that long-winded here, so I'll try to make it short and concise... Basically, I don't believe going to a 'Parallel Flow' set-up could do anything but HELP - The science doesn't back-up any other position in my opinion. Here's my logic, you are right about the fuel velocity and vapor lock being a critical concern and condition to avoid. With respect to velocity, the liquid (in this case fuel) is primarily effected by two physical conditions, change in flow direction and more importantly change in inner orifice diameter (in particular, going from small diameter into big diameter - This can create VAPOR LOCK and induces a lot of turbulence). When you switch your fuel system from series to parallel, you reduce the number of turns and the number of times the fuel goes from a small orifice into a big orifice, so going to a parallel design should help reduce the chance of vapor lock and keep the fuel velocity up. Fuel pressure is at play here too...less turns and less turbulence leads to lower frictional loss and the preservation of closer fuel pressures across all fuel injectors. So, I think Parallel design in theory should help keep more even fuel pressure across all rails too. *ONE NOTE: Everything changes if we start talking about using aftermarket fuel rails. It's all about maintaining a constant inner orifice diameter (and having a large enough inner diameter orifice to handle to required volumetric needs); -AN fittings and hoses do exactly this. So if you step up you whole fuel system, the advantages of going to 'Parallel' design start to decrease. That being said...If you were building a 1000HP motor, you would still want the most robust and bullet-proof fuel system design and I think 'Parallel' wound still be the way to go; I've seen many big horsepower motors used in professional motor sports (drag racing to circle track) use 'Parallel' designs. It will probably be a hotly debated topic for many years to come... Thanks again for the post!!! 👍👍
thanks for the comprehensive response. that's a good point about the inner diameters/sharp turns of the aftermarket rails throwing a wrench in the works. taking the pro parallel argument one step further, do you think there's consistency/reliability to be gained by going semi returnless and going: fuel pump --> fuel distribution block --> fpr. with the distribution block having 4 equal length lines going to the end of each fuel rail? I'd imagine this provides more consistent pressures at each injector, and keep the return fuel from getting cooked by the engine. This would decrease fuel velocity through the rails again, but if I read your post correctly that's a moot point. Right?
+ryan lewis - This sounds like it would provide the most consistent fuel pressure at the rail, but if I read your comment correct, there is no return fuel flow back to the tank at all. Is this correct? If so, I think this would burn out the fuel pump, as those units are designed not to flow against a dead-head line. As I understand, these fuel pumps can push the volume but can't deal with very much back-pressure.
SubaruONLY I'm talking about a semi returnless setup. Not a full in returnless setup where the fpr is integrated into the tabk/pump. basically having the fuel going to a distribution block, fuel pressure reg and then the tank. the distribution block would supply fuel to the rails and act as a pass through for fuel going to the return lines (instead of sending it through the rails and then the reg). thanks for the reply!
+ryan lewis Ah, OK - I got you. I have not seen this type of setup first hand, so my perspective is limited in that respect. BUT, I will try to apply my experience and scientific rationale to weigh in... As I see things, having the fuel flowing at good consistent rate with plenty of volume and at the right pressure (for the full RPM range) is the most critical thing to achieve. From there, you can try to cool the fuel and avoid any vaporization, which can cause vapor lock (basically a bubble of vapors in the fuel line that blocks liquid fuel from passing through), which YOUR design/approach focuses on addressing, I believe. I don't have any data to back this up, by I think allowing the fuel to flow back to the engine is a good thing overall, as it prevents the fuel from sitting in the rail and absorbing all the engine's heat. Heat is going to transfer into the fuel no matter what you do, it's really just a question of how you minimize it. I think removing the return line (from the rails) would cause more heat to transfer into the fuel (at least at the rails) and might increase the chance of crossing over fuel's vapor pressure threshold and create vapor lock. So, overall I wound go with parallel but just make all the lines and rails bigger to supply all the fuel your particular engine combination requires.
Hey luke important question ..on N.A set up can running parallel fuel line increase performance on n.a set up .and any fuel pump upgrades for a N.A set up?
Hey bud - thanks haven’t gone too deep into the high performance NA motors, but I don’t think the fuel supply is as much of an issue with NA motors. So not sure if it would help much.
@@SubaruONLY thanks luke I just feel like u can give a N.A power just as a turbo can maybe not much power but something is something ..another question my 06 forester ..can my computer capable of flash tunning or just subaru computer are they flashable seen someone make a N.A impreza turbo and he had flashed and tune the stock wrx tune setup and it work great
@@SubaruONLY I mean I have a video of a N.A non turbo impreza get flash tuned with a cable off ebay if that N.a ecu can be flashed wonder if it's good for the forester.same motor
Did a 5 min search and looks like these NA ECUs can be tuned (COBB briefly offered an Accessport for 06-07 NA Imprezas, but it provided less than 10HP, didn’t sell well, and as a result, was discontinued), however, the gains for the cost are debatable. I’d focus on adding lighter parts and suspension mods to make the car more fun - just my opinion... cheers and good luck!!! 👊
Ok, Im running a parallel system and wanting to drain the fuel lines of bad e85. I have drained fuel tank by the in tank fuel filter(under back seat) thinking of disconnecting the line attached to the fuel regulator to drain old out of lines? By Is this the best way or there a better easier way.. novice here.. thanks
Just got back in the subaru game after buying a GT (st/b) foz as a daily. What sorta power level would you recommend doing this? Currently the cars up pipe, td04, 3" exhaust, EBC (15psi), walbro pump and an intake.
Thanks for the question and checking out the video - Much Appreciated! Yes, I did flare the stock fuel lines using an "ISO bubble flaring kit". They say it's for brake lines but I was able to use it to flare the stock hard fuel lines (where I cut them) very easily. Here's a link to the Flaring Kit I used for Reference - It's a $30 kit from Amazon: www.amazon.com/dp/B0015PMZMU/ref=cm_sw_r_cp_apis_1491187829774
+Jon Cole I found it at a specialty shop. I’ll try to hunt it down. I think I searched for this term, “stainless steel y splitter”. They manufacture made OEM parts for domestic manufacturers I think.
I checked it out. I would go with something that had more of a barb fitting for the hose, so the fuel line can’t slip off. The inner size should be ~ 5/16”, which is about 7mm. Here are a couple of options: 1) rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F232853108745 2) rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F311095859089 Hope this helps. See how those have the barb ridges to hold the hose on once it is slipped over - still use high pressure fuel line clamp of course. The stainless option is way more expensive but stainless is really nice to use as it doesn’t corrode at all, and it will probably be a better quality casting too. But the brass option should be fine too. Bet you can find these on Amazon too - FYI. Good luck buddy! Let me know how it goes! 🤙
Sorry guy, still the same back up pressure point...just at the splitter down to were the rail w.o the regulator...if u have 2 regulators on each side then it would work. But nah lol still going to have more pressure on the rea4 rail
Running lean p2096 ..when I keep a consist thottle thru out drive code wont pop up until hard thottle... I did head gasket job.. dought it be that...I thought is fuel pump fuel filter ima do that and injector those are what I think is causing it or exhuast leak but I got full bolt on..and obx long tube equal lenght headers and everything tight
Sounds like a potential leak somewhere - intake side is very common for lean condition. That would be my first target area to look over closely. Good luck buddy! 👍
Hello I have a couple of questions for everybody and the comment section does anybody know if there is an aftermarket fuel system for the ej22 phase 1?
Thanks Luke, Great Video but , there is a better way. You use a fuel rail to AN 6 converters, run your hoses to from , in and out with AN6 fittings and plumbing to the fuel rails , fuel pressure regulator and return lines. and to your fuel pumps and fuel filters. I'm a gyroplane nut and thats what I'm using on my Subaru engine.
I see this is an old video. Just now getting into subarus. Your only running 4 injectors with probably a 255 pump. V8s run the same pump with pressures of 45psi and higher and dont have this problem. Try going to a bigger size line and your problem would go away!
Hey man! Thanks for the message! Yes, I think you are 100% correct - great advice! Bigger lines would be very good call! Side note, I actually started my automotive journey with small block Chevy engines - so some pretty familiar with your reference perspective. I spent many years drag racing and circle track racing small block chevys in early 2000s. Had a couple 68 Cameros, 64 nova, and others! Good times man!
![[MV] A leap of faith...ความเชื่อใจครั้งสุดท้าย (From "Petrichor the series")](http://i.ytimg.com/vi/U1piZH2CNXA/mqdefault.jpg)
This is hands down the best quick explanation I've ever seen for our EJ fuel systems.
Sweet - thanks buddy!!!
@@SubaruONLY In your experience, is there a point in which you would recommend going with a parallel setup over stock on an otherwise stock USDM sti?
Probably not, to be honest. Feel like the OEM setup is fine for anything that remains totally OEM tune. Can’t hurt, but there’s always the chance something isn’t reconnected quite right, so there’s always a slight risk when doing any modification.
Interesting take on piston 4 failures. From what I've come across within the Subaru community, lean mixture in cylinder 4 stemming from OEM series fuel line system was to blame (you did touch on this). Limited cylinder 4 cooling does make sense too though. Thanks for the thorough cooling system break down.
that... is bloody brilliant... this needs to get added to the build list
I will definitely be going this route for the R-STi build at some point!! 👊
Maybe you could make playlist with all the diy upgrades you have shown us ;-)
Good idea. I’ll try to set that up this week.
Thank you, You saved me a lot of money. I am in the trade and have built many cars and never even considered doing this.
Awesome. Glad it helped! 🤙
If anyone is having a problem keeping up with him talking. Go to setting and use the play back option and select the 0.75x speed! Your welcome!
lol
nice video really helpful and a great cheaper way than paying out $700 for some kit ! well done and thank you .
Going hard from first to second gear the engine can sometimes lose power for a second you think this could be part of the problem.
Thanks Jason
Hmmm. Would have to dive into more details to tell. Could be a fueling issue to timing.
@@SubaruONLY hello again been looking through your videos was wondering if you done a one on fitting a bigger turbo
Hi, no I haven’t. But will think about that for a future video. Cheers!
@@SubaruONLY thanks for reply Luke
Hi Luke were can I get one of them fuel line splitters and all the other bits m8
Glad I found this video before buying parts. It gave me the big picture. Thanks
Awesome! 👊
Thanks Luke, loving your videos mate. Super informative and detailed 👌
Hey Luke I have a very important question regarding my 06 forester ej2.5 non turbo I watch alot of ur videos and I can say love it and interesting .. this video does this apply to non turbo ej2.5 too
It does. But only really needed if making more HP than stock.
Hey being wonder If youd be able to do a re take on the parallel fuel delivery system n how to do it or like a detail n more in depth
Nice, Simple and to the point, great information!
+Manuel Berrueta
Awesome - Thank you. That is what I'm trying to do - Provide value in every video, so people feel like they actually gained something or thought about things in a slightly different way. Anyways...THANK YOU! More to come!
Between parallel fuel and the reverse cooling mods If Subaru is so cool why don't they do these things from factory? Thanks for helping me realize Subaru has lots of room for improvement.
Lol. Thanks. 😂
Awesome video that's simple and to the point!
+L MT
Thanks! Tried to do exactly that!
Came here from another vid of yours
If you do a remake of this can you talk about pulling off the headers and looking at the exhaust valves.
While back when I looked at mine all were the "rich white colour " but the last one on fuel rail
For sure buddy! Will do - thanks!
Is it possible to remove all the hard lines and only run the OEM fuel rails with parallel fuel lines? Or do you need to upgrade the fuel rails as well? If so can you do a tutorial on how you hookup the hoses to the OEM lines
This way you invert the order the cylinders get fuel. It should be after the split one line going to the front of the right fuel rail and the other to the rear of the left fuel rail (left and right as in you scheme).
+siliconfilm Interesting. I'm curious - What's the logic doing this? Does it create an advantage or safer running conditions?
SubaruONLY Honestly I have no idea if changing the firing order with respect to stock will make any difference. Many seem to be doing the way you did. But if you take a look at the Perrin fuel rails they are setup the way I described, which maintains the firing order unaltered.
+siliconfilm Hey - thanks for the follow-up. So I don't change the ignition firing order - I keep it 100% stock. For the fuel system...The side that the fuel enters the fuel rails doesn't really affect how or when the injectors distribute the fuel (unless we start getting really technical). All that matters is how much pressure drop you see across all fuel rail points and not putting too much heat into the fuel before it enters the rails. Too much pressure drop and you'll end up with inconsistent fuel delivery and too much heat transmitting into the fuel line could cause vapor lock (blocks flow of liquid fuel). Hope this answers at least part of your question. Cheers my friend!! 🤙🤙
SubaruONLY great so the firing order stays the same. One thing you can do to keep fuel cooler is running the fuel lines over the intake manifold. I guess if you use large aftermarket fuel rails and larger fuel lines you could also keep the design in series and the greater flow should fix the allegedly lean condition of cylinder #3.
Old video, I know, but how do you re-flare / re-bead the oem fuel lines after you cut out that section so that hoses can't slip off?
hey great video!
do you also have some reccomnedation for which injectors i should use? I need about 650cc/750cc injectors.
Excellent content!
Recently discovered a fuel leak under the intake manifold of my 05 sti. In the process of repairing the line, would it be wise to go with a paralleled set up? Would I need a tune to run this modification?
For the tuning question, I think the answer is NO.
Hey man. No tune needed for switching to parallel fuel line setup. Is it needed, not likely for near stock STi. Will it hurt, not at all if installed correctly. Good luck!
@@SubaruONLY Do you have to run a fuel pressure regulator if you're running stock power? Would be nice to do this setup when fixing my fuel leak without having to spend money I don't have on a fuel pressure regulator.
Interesting you're using standard lines, can I ask why you chose that route and not braided? Personal choice maybe? See my videos for my 472bhp JDM TYPE R, parallel rails are next for me and trying to weigh up options 👍
+Aaron's Videos Thanks for dropping the question. And btw, your car sounds awesome - I will check it out. I went with stock lines cause I was staying with the stock rails and those rails have the smallest inner diameter/choke point at their inlets and outlet points for the entire fuel system. So, go bigger diameter braided would actually not have helped the flow of fuel in my case.
HOWEVER, if I went to larger rails, YOU are 100% on target and larger ID fuel lines (braided or any high performance type - there's so many options out there now) would be the only way to go. If I stayed with stock lines at that point, I wouldn't be taking advantage of the new ID and associated fuel capacity of my new rails!
Nice video. Exactly what I was looking for! Keep the videos coming!
+Irene Guerin
Stoked to hear - THANK YOU! More coming, stay tuned.
I'm interested in modifying my stock fuel lines on my 2003 wrx, everything is off the longblock for a jdm block swap anyways and I want to create a safer fueling system while I'm at it. Do you have any ideas for the fuel pressure regulator faceplate on the cylinder 1&3 factory fuel rail? I'm thinking of chopping it off and having the hole welded up. But if I could just tap it and use it as a return line so that both fuel rail return lines lead to the same FPR that would be great. I can send pictures of the concept I have in mind I would love to have your input. Love the channel, thanks a ton!
Awesome man. Yes, send pictures and info to my email: SubaruOnlyShow@gmail.com
SubaruONLY Tomei actually makes a FPR adapter to a 1/8 npt thread. So I'm going to use 2 passenger side fuel rails with these adapters leading to my return lines.
Nice! Thanks for sharing this! 🤙🤙
What kinda manifold is that? Need that bolt pattern for my heads cant find it anywhere.
You saved my pistons i owe you my left testie
+Glenn Andrews legit. Keep it rolling!! 🤙🤙
@@SubaruONLY I’m glad to join your channel and have just bought myself some parts off of your Amazon Store. Would you like to consider making videos on how to make more power and torque in a non turbocharged ej motor? I know that it’s not the most cost effective way to make power but ( I love the na ej as it is playful and peppy, just not powerful) what can be done to a Sohc EJ22 engine?
Supercharger.
@@SubaruONLY That’s works well for me, any recommendations on the type of supercharger and brand to best utilize for a fun street/ occasional track car?
Think the ones used for OEM BMW applications have been used with some success.
So is this the cause for the known 2-3k rpm drop of power/stutter? Thanks
Would you say this is the main cause of the famous cylinder #4 ringland failure on the older STis?
+JackstandJohnny You are 100% correct about cylinder #4 being the most common failure location. This is also a highly debated question, here are my thoughts:
(1) The fuel distribution is definitely one of the culprits but I think there are some other things at play here as well.
(2) For example, the knock sensor is nearest to this location and I have read that Subaru tunes their ECUs to advance spark on this cylinder more than others to creep up on highest advance possible, then it uses the threshold for that cylinder as a proxy for max timing advance on all other cylinders.
(3) I also think the fact that the cylinder is in the back of the engine plays a role as this causes more heat soak than the two front cylinders.
I'm sure that's not all of the reasons but those seem like some big ones to me. Hope this helps or at least keeps the wheels turning...Thanks 👍👍
Watch 'GetaDomTune' in TH-cam. He explains cylinder 4 ringland faulure. And has a proven solution.
Totally makes perfect sence balance is key. NOTE TOO SELF!!! lol how did your set up turn out?
Main problem is lack of forged internals on a boosted engine.
Working great. 👊
Is the distance between two sides the same? Or is that over thinking?
How did you take the stock fpr out of the system ? You must of used a dual input regulator for this to work or the first fuel rail would have no pressure ?
What Brand kit do you sugests to buy
Why is the regulator at the end and not before the first cylinder?
It helps keep the pressure even across all fuel injectors. This is because the pressure drop happens right after all the injectors, which helps act as a buffer to minor fluctuations.
I got pink sti injectors should i hook it up in parallel
Parallel is good regardless of the injector size. And, as the fuel flow requirements increase, parallel flow only helps more. So, in other words, can’t hurt at all!
What brand or Ver manifold you are using on your EJ20G sti motor?
Would you go cheap on a fuel rail? I know not to on things like injectors, pump.. but what about fuel rail?
+Mark Villanueva Actually, I would because I feel my evaluation of inner ID and factors that control things like turbulence is adequate to make a good judgement. The one think I can’t really assess is the quality of the material used - that’s the one risk, but I’ll just keep eye on wear and tear on the parts.
What year is it stock series? I know the 08-14 stis are parallel from factory. Dom has a whole video on it. Cant remember what all years and models it includes
Whats is a good brand of fuel pressure regulator thst you recomend? Thst does not brake the bank.
Well... like so many parts, this is a part that is a little costly if you buy from reputable manufacturers - which I 100% do recommend doing. There are cheapo eBay ones out there but this part is something that can cause major engine damage if it fails or starts to become inconsistent - so stick with the high quality manufacturers. Here’s the ones I like: (1) AEM, (2) Radium, (3) Tomei, (4) Deatschworks, (5) Aeromotive, or (6) FuelLab. These are all legit and reliable options!!! 👊
Radium, aeromotive, both make good FPR
Have you heard of the GR sti stumble? Was wondering what you're take on it is.
+moog - I have but have not personally gone down this rabbit hole. From what I understand, it's basically the OEM fuel dampners that are impacting higher than stock fuel flow characteristics. This can create that stumble between 2000-3000 RPM - Super annoying!
SOLUTION: Many have had good luck using the IAP or the COBB kit - I would try one of these. Thanks and good luck. Let us all know how it goes! 👍👍
I am trying to resolve a gr stumble. That's how I found your video. I have 1000cc injectors on factory rails and lines and I have a aeromotive fpr. I still have a stumble. I'm looking at new larger rails like iag plumbed in parralel. I think your mod may be a better fit for me.
Good luck. Hope that fixes it.
Love the videos, want more, got your notifications on!!
+Connor Swanson Thanks Man!!!
@@SubaruONLY this is great knowledge to tackle the flaws and short comings of the ej motors! Would this work on a stock car?
Yes, it would. Cheers!
I've been doing some reading and saw a thread on nasioc discussing why series is better than parallel for our engines. Not saying it's right or wrong, but since the point was that since none of the cylinders are firing injectors at the same time (or the overlap is negligible) there isn't much gain to be had by going parallel. They were also saying one of the reasons people have problems with the junky agency power rails is due to the fuel velocity being halved in each rail and somehow inducing vapor lock. BTW, just found out about your channel and subscribed. Keep up with the awesome content! interested to hear your thoughts... Ryan
+ryan lewis
Thank you for checking out the channel and for taking a second to post a comment! Much appreciated! The whole discussion
on 'Parallel vs Series' Fuel System is is a hotly debated topic for sure - It has been for many years in Subaru circles. I think there are probably compelling arguments for either position. As you get into the technical details, there is a lot happening here, as you touch on by mentioning the aftermarket rails and the impact to fuel flow velocity.
One could probably write an essay on this question alone but I don't think anyone what's to see something that long-winded here, so I'll try to make it short and concise...
Basically, I don't believe going to a 'Parallel Flow' set-up could do anything but HELP - The science doesn't back-up any other position in my opinion. Here's my logic, you are right about the fuel velocity and vapor lock being a critical concern and condition to avoid. With respect to velocity, the liquid (in this case fuel) is primarily effected by two physical conditions, change in flow direction and more importantly change in inner orifice diameter (in particular, going from small diameter into big diameter - This can create VAPOR LOCK and induces a lot of turbulence). When you switch your fuel system from series to parallel, you reduce the number of turns and the number of times the fuel goes from a small orifice into a big orifice, so going to a parallel design should help reduce the chance of vapor lock and keep the fuel velocity up. Fuel pressure is at play here too...less turns and less turbulence leads to lower frictional loss and the preservation of closer fuel pressures across all fuel injectors. So, I think Parallel design in theory should help keep more even fuel pressure across all rails too.
*ONE NOTE: Everything changes if we start talking about using aftermarket fuel rails. It's all about maintaining a constant inner orifice diameter (and having a large enough inner diameter orifice to handle to required volumetric needs); -AN fittings and hoses do exactly this. So if you step up you whole fuel system, the advantages of going to 'Parallel' design start to decrease.
That being said...If you were building a 1000HP motor, you would still want the most robust and bullet-proof fuel system design and I think 'Parallel' wound still be the way to go; I've seen many big horsepower motors used in professional motor sports (drag racing to circle track) use 'Parallel' designs. It will probably be a hotly debated topic for many years to come... Thanks again for the post!!! 👍👍
thanks for the comprehensive response. that's a good point about the inner diameters/sharp turns of the aftermarket rails throwing a wrench in the works.
taking the pro parallel argument one step further, do you think there's consistency/reliability to be gained by going semi returnless and going: fuel pump --> fuel distribution block --> fpr. with the distribution block having 4 equal length lines going to the end of each fuel rail? I'd imagine this provides more consistent pressures at each injector, and keep the return fuel from getting cooked by the engine. This would decrease fuel velocity through the rails again, but if I read your post correctly that's a moot point. Right?
+ryan lewis - This sounds like it would provide the most consistent fuel pressure at the rail, but if I read your comment correct, there is no return fuel flow back to the tank at all. Is this correct? If so, I think this would burn out the fuel pump, as those units are designed not to flow against a dead-head line. As I understand, these fuel pumps can push the volume but can't deal with very much back-pressure.
SubaruONLY I'm talking about a semi returnless setup. Not a full in returnless setup where the fpr is integrated into the tabk/pump. basically having the fuel going to a distribution block, fuel pressure reg and then the tank. the distribution block would supply fuel to the rails and act as a pass through for fuel going to the return lines (instead of sending it through the rails and then the reg). thanks for the reply!
+ryan lewis Ah, OK - I got you. I have not seen this type of setup first hand, so my perspective is limited in that respect.
BUT, I will try to apply my experience and scientific rationale to weigh in...
As I see things, having the fuel flowing at good consistent rate with plenty of volume and at the right pressure (for the full RPM range) is the most critical thing to achieve. From there, you can try to cool the fuel and avoid any vaporization, which can cause vapor lock (basically a bubble of vapors in the fuel line that blocks liquid fuel from passing through), which YOUR design/approach focuses on addressing, I believe. I don't have any data to back this up, by I think allowing the fuel to flow back to the engine is a good thing overall, as it prevents the fuel from sitting in the rail and absorbing all the engine's heat. Heat is going to transfer into the fuel no matter what you do, it's really just a question of how you minimize it. I think removing the return line (from the rails) would cause more heat to transfer into the fuel (at least at the rails) and might increase the chance of crossing over fuel's vapor pressure threshold and create vapor lock.
So, overall I wound go with parallel but just make all the lines and rails bigger to supply all the fuel your particular engine combination requires.
Can you come out if the fuel rails into a y to the stock pressure regulator?
Why would you
But wouldn't parallel fuel system make car respond better not just for hight horse power?
doesn't really help for response. Only helps prevent fuel starvation, which usually occurs in the upper end of the RPM range.
Luke! New sub bro. Hello from the6.
Hey luke important question ..on N.A set up can running parallel fuel line increase performance on n.a set up .and any fuel pump upgrades for a N.A set up?
Hey bud - thanks haven’t gone too deep into the high performance NA motors, but I don’t think the fuel supply is as much of an issue with NA motors. So not sure if it would help much.
@@SubaruONLY thanks luke I just feel like u can give a N.A power just as a turbo can maybe not much power but something is something ..another question my 06 forester ..can my computer capable of flash tunning or just subaru computer are they flashable seen someone make a N.A impreza turbo and he had flashed and tune the stock wrx tune setup and it work great
👍 hmm, good question. Not sure if you can flash those NA ECUs. Let me know what you find! Cheers! 👊
@@SubaruONLY I mean I have a video of a N.A non turbo impreza get flash tuned with a cable off ebay if that N.a ecu can be flashed wonder if it's good for the forester.same motor
Did a 5 min search and looks like these NA ECUs can be tuned (COBB briefly offered an Accessport for 06-07 NA Imprezas, but it provided less than 10HP, didn’t sell well, and as a result, was discontinued), however, the gains for the cost are debatable. I’d focus on adding lighter parts and suspension mods to make the car more fun - just my opinion... cheers and good luck!!! 👊
Ok, Im running a parallel system and wanting to drain the fuel lines of bad e85. I have drained fuel tank by the in tank fuel filter(under back seat) thinking of disconnecting the line attached to the fuel regulator to drain old out of lines? By Is this the best way or there a better easier way.. novice here.. thanks
Just got back in the subaru game after buying a GT (st/b) foz as a daily. What sorta power level would you recommend doing this?
Currently the cars up pipe, td04, 3" exhaust, EBC (15psi), walbro pump and an intake.
Nice man. Sounds like more power is what you’re looking for. I’d start with larger injectors and a tune, that should wake the engine up a bit!!! 👍
@@SubaruONLY Another question you might be able to help with. what are the stock auto's in the turbo models good for power wise.
I hear around 350-400 WHP.
@@SubaruONLY Works for me. Only after around 200kw @ all fours. :D
👍
Did you have to flare the stock lines where you split them for the Y fitting?
Thanks for the question and checking out the video - Much Appreciated!
Yes, I did flare the stock fuel lines using an "ISO bubble flaring kit". They say it's for brake lines but I was able to use it to flare the stock hard fuel lines (where I cut them) very easily.
Here's a link to the Flaring Kit I used for Reference - It's a $30 kit from Amazon: www.amazon.com/dp/B0015PMZMU/ref=cm_sw_r_cp_apis_1491187829774
Does this tool do 37 degree flares?
What intake manifold is that ?
Hi What's the internal diameter of the y splitter? Also where did you get it from I can only find brass splitters on e bay.
+Jon Cole I found it at a specialty shop. I’ll try to hunt it down. I think I searched for this term, “stainless steel y splitter”. They manufacture made OEM parts for domestic manufacturers I think.
Hi do you think this will work?
rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F382418735204
I checked it out. I would go with something that had more of a barb fitting for the hose, so the fuel line can’t slip off. The inner size should be ~ 5/16”, which is about 7mm. Here are a couple of options:
1) rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F232853108745
2) rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.com%2Fulk%2Fitm%2F311095859089
Hope this helps. See how those have the barb ridges to hold the hose on once it is slipped over - still use high pressure fuel line clamp of course. The stainless option is way more expensive but stainless is really nice to use as it doesn’t corrode at all, and it will probably be a better quality casting too. But the brass option should be fine too. Bet you can find these on Amazon too - FYI. Good luck buddy! Let me know how it goes! 🤙
Or do I have to upgrade to a 2 port regulator?
Hi bro I have EJ 25 D engine there's any advice to upgrade to get more power something like extra 50 to 100 HP safety 😅
Can you do the split parallel with the 2017 ej25's
Good video straight to the point no bs
Thanks. Try to keep them focused and to the point for sure. Cheers buddy!!! 👊
Hey luke need a lil guides ..
Sorry guy, still the same back up pressure point...just at the splitter down to were the rail w.o the regulator...if u have 2 regulators on each side then it would work. But nah lol still going to have more pressure on the rea4 rail
Running lean p2096 ..when I keep a consist thottle thru out drive code wont pop up until hard thottle... I did head gasket job.. dought it be that...I thought is fuel pump fuel filter ima do that and injector those are what I think is causing it or exhuast leak but I got full bolt on..and obx long tube equal lenght headers and everything tight
Sounds like a potential leak somewhere - intake side is very common for lean condition. That would be my first target area to look over closely. Good luck buddy! 👍
Pressure is more around 43psi from factory
Hello I have a couple of questions for everybody and the comment section does anybody know if there is an aftermarket fuel system for the ej22 phase 1?
Any of the aftermarket fuel system upgrades for “EJ” style motors will work. Check out IAG - they got a some good options!
@@SubaruONLY for the 1996 ej22?
Yep - and great engine!
I have a question, it could be possible make a conversion of a WRX Sti (Engine EJ207) for Impreza Hatchback 2010 (Engine EJ204) ?
I think is possible!
So you don't need to left hand fuel rails to do this
No. Should be fine with the original fuel rails. Cheers 😁
Hey Luke, can you do this with a stock fpr?
You could! And it should work just fine! Good call!
Good to know man! An aftermarket fpr would be nice to have down the line along with the AN fittings.
Totally - but running a parallel setup with all stock stuff is a good step in the right direction! And super low cost! 👊
Can you use parallel into a N/A eninge?
Yes, absolutely. It would be good for a higher HP NA motor for sure! 👍
Appreciate your response,🙏🙏 this is so helpfull. I got a 2004 blob eye 2.0R 😊
Super cool, Thanks, Peace
Can I do that to the stock intake ?
Yes. 100%.
SubaruONLY cool thanks appreciated nice and awesome channel btw
Dude - thanks!!! 😁
Hey Man can you contact me at ivan.rotor@gmail.com
Have you made the diy on how to install
+Jowe Fierro Hey man. Thanks for reaching out. I have not done this yet but I am planning on doing one in the future. Stay tuned 🤙🤙
Excellent . I'm excited. I wanna put mine on my sti it i wanna watch your video first .
Can you do more performance parts
+Jowe Fierro Cool. Good luck!!
+Jowe Fierro Hell yea. New shop in the works and taking this whole Subaru lifestyle to the next level - stay tuned!!!
I want to know you FPR brand and model. Cheers :)
Phoenix Industries. Made is US.
Great videos like always keep it up (scoobysangha)
Thanks man!!! Will do! 😁
Thanks Luke, Great Video but , there is a better way.
You use a fuel rail to AN 6 converters, run your hoses to from , in and out with AN6 fittings and plumbing to the fuel rails , fuel pressure regulator and return lines. and to your fuel pumps and fuel filters. I'm a gyroplane nut and thats what I'm using on my Subaru engine.
I see this is an old video. Just now getting into subarus. Your only running 4 injectors with probably a 255 pump. V8s run the same pump with pressures of 45psi and higher and dont have this problem. Try going to a bigger size line and your problem would go away!
Hey man! Thanks for the message! Yes, I think you are 100% correct - great advice! Bigger lines would be very good call!
Side note, I actually started my automotive journey with small block Chevy engines - so some pretty familiar with your reference perspective. I spent many years drag racing and circle track racing small block chevys in early 2000s. Had a couple 68 Cameros, 64 nova, and others! Good times man!
I'm such a tart... I ran mynparallel to the back of the fuel rail first 💀🔫
Dude looks like a white R Kelly
But In all seriousness, thanks for the video. Super useful🤙🏻🤙🏻
Lol. Thanks man!!! 👊
Talks way to fast,
Ahhh man…I was a rookie back then. But hear ya!