Scottydunno Posted October 11, 2019 Share Posted October 11, 2019 So, I want to do a top feed injector conversion on my 05. I also want to keep it stock looking. What factory parts can I use to do this? Scotty Link to comment Share on other sites More sharing options...
Nonamedude Posted October 11, 2019 Share Posted October 11, 2019 Well they aren't exactly easy things to see, but the 08 and later (and maybe the 07) use top feeds so you could just use those parts. You'd need injectors, fuel rails, tgvs. I think that's it but search around. This is a common mod and you should be able to find a walk through. Are you planning to move to a bigger turbo. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
awfulwaffle Posted October 11, 2019 Share Posted October 11, 2019 (edited) I used 07 wrx rails and FPR, with rubber fuel hose bridging the rails. I have a shot of it in post 2 here: https://legacygt.com/forums/showthread.php/build-thread-time-280134.html If I had to do it again, I'd use 08-14 WRX/STI, or 07-09 LGT rails/FPR. Reasons being, FPR sits on the driver side of the engine, and the line ends should actually bolt up to stock manifold points. I used IAG TGV deletes because my schedule got accelerated, but any factory top feed TGVs will work. If you're interested, I have mostly complete top feed deletes from an 06 WRX. Just need the gasket surfaces sanded. Edited October 13, 2019 by awfulwaffle They were 07 WRX rails, not 08. 08+ works Link to comment Share on other sites More sharing options...
Nonamedude Posted October 11, 2019 Share Posted October 11, 2019 If I had to do it again, I'd use 11-14 WRX, or 07-09 LGT rails/FPR. If you're interested, I have mostly complete top feed deletes from an 06 WRX. Just need the gasket surfaces sanded. What's your turbo and fueling setup? From what I can tell the fueling is a far down the road upgrade. I know max capacity is running nearly 300hp and a vf52 without any real issues on stock fueling. But yea if you're doing it, you're gonna have to buy tgv so might as well get a deleted one while you're at it. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
gkinslow Posted October 11, 2019 Share Posted October 11, 2019 What's your turbo and fueling setup? From what I can tell the fueling is a far down the road upgrade. I know max capacity is running nearly 300hp and a vf52 without any real issues on stock fueling. But yea if you're doing it, you're gonna have to buy tgv so might as well get a deleted one while you're at it. Sent from my iPhone using Tapatalk close, but you'll need a better fuel pump than stock or ridiculously generous dyno to hit 300whp and will nearly max out your stock injector's duty cycle. I'm still running the stock rails, lines, and FPR at 450whp. vf52 with stock fueling (upgraded pump) got me 290whp 319wtq. Link to comment Share on other sites More sharing options...
awfulwaffle Posted October 11, 2019 Share Posted October 11, 2019 ID1000s, DW65c, BNR Evo III16G. No idea on power since I'm still running on wastegate. Targeting a safe 350 on E85 to start, 300 on 93 Link to comment Share on other sites More sharing options...
Nonamedude Posted October 11, 2019 Share Posted October 11, 2019 Yea I think he said in my rebuild thread that he was at like 95% load on the injectors or maybe the pump and was around 270 or 280. I'd have to look for the exact. My comment was mostly why move to a top feed. I know the side feed have some problems with gumming up but the cost of the conversion doesn't seem worth it until you have at least vf52, catless UP, better downpipe, upgraded tmic, and of course a tune. But that even if you have all that you can still do pretty well on stock high mileage side mount injectors. Mostly just seems like you should already have a lot of money and time in the car and if you've got that much money and time, you'd likely know what you need for the conversion. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
awfulwaffle Posted October 11, 2019 Share Posted October 11, 2019 A lot of tuners will say that a top feed will have dramatically better spray pattern than a sidefeed of equivalent flow rate, which makes them more predictable and improves combustion efficiency. Wonder if there's a comparison with pictures somewhere. I did it because there's more available in the top feed side of things, and because I got a fantastic deal on the injectors. Plenty of people making power on sidefeeds though, including a friend of mine running DW1000 sidefeeds on a Stage 2 IAG FXT. Link to comment Share on other sites More sharing options...
gkinslow Posted October 11, 2019 Share Posted October 11, 2019 Most tuners will tell you anything above 850cc side feed is a bad idea. Doesn't mean its impossible or shouldn't be done. Just takes more time to fine tune. Link to comment Share on other sites More sharing options...
Scottydunno Posted October 11, 2019 Author Share Posted October 11, 2019 Well they aren't exactly easy things to see, but the 08 and later (and maybe the 07) use top feeds so you could just use those parts. You'd need injectors, fuel rails, tgvs. I think that's it but search around. This is a common mod and you should be able to find a walk through. Are you planning to move to a bigger turbo. Sent from my iPhone using TapatalkI know I'm going to go a bigger turbo, I just don't know which and what I'll need to hit my goal of 300-350 whp. I know I can do it on larger side feeds, but I've heard of tuning issues when going bigger than a 740cc. Personally, whether it's true or not is in material. In all my years of cars and what not, I've never had issues with top feed style, but side feed/TBI style injectors, not so much. Scotty Link to comment Share on other sites More sharing options...
Scottydunno Posted October 11, 2019 Author Share Posted October 11, 2019 I used 08 wrx rails and FPR, with rubber fuel hose bridging the rails. I have a shot of it in post 2 here: https://legacygt.com/forums/showthread.php/build-thread-time-280134.html If I had to do it again, I'd use 11-14 WRX, or 07-09 LGT rails/FPR. Reasons being, FPR sits on the driver side of the engine, and the line ends should actually bolt up to stock manifold points. I used IAG TGV deletes because my schedule got accelerated, but any factory top feed TGVs will work. If you're interested, I have mostly complete top feed deletes from an 06 WRX. Just need the gasket surfaces sanded.Thank you! Exactly what I was asking for! At that point, I can mod the TGVs and delete them while I gather parts and eventually get time to do it. Scotty Link to comment Share on other sites More sharing options...
awfulwaffle Posted October 11, 2019 Share Posted October 11, 2019 (edited) No problem, glad to help. I'd post on NASIOC in WTB and just see what pops up if you have time to wait. I ended up getting all the hardware I need to do the conversion (rails, OEM TGVs, FPR) for $150 bucks. I'd also contact someone like SubieRecycler about injectors. They got me some used DW1000s for $150 shipped, which gave me plenty of buffer to get them flowed and checked by DW and still come out ahead. I actually still have them because I pulled them off and swapped for ID1000s a friend had sitting around while troubleshooting, and never swapped them back. The garbage pile grows forever when you own a turbo Subaru, I guess. Edited October 11, 2019 by awfulwaffle Link to comment Share on other sites More sharing options...
Nonamedude Posted October 11, 2019 Share Posted October 11, 2019 I know I'm going to go a bigger turbo, I just don't know which and what I'll need to hit my goal of 300-350 whp. I know I can do it on larger side feeds, but I've heard of tuning issues when going bigger than a 740cc. Personally, whether it's true or not is in material. In all my years of cars and what not, I've never had issues with top feed style, but side feed/TBI style injectors, not so much. Scotty For sure. Certainly wasn't trying to dissuade you. I thought all the lgt had side feed at first and wasn't upset to find out I had top feeds. Sounds like you're on the right track then though. Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
Scottydunno Posted October 11, 2019 Author Share Posted October 11, 2019 For sure. Certainly wasn't trying to dissuade you. I thought all the lgt had side feed at first and wasn't upset to find out I had top feeds. Sounds like you're on the right track then though. Sent from my iPhone using TapatalkNo worries. I'm still fairly new to these cars, but not afraid to research, learn, and of course have fun. I'm not new to turbo cars as my toy is an 89 Daytona Shelby. But I appreciate what input you may have. Scotty Link to comment Share on other sites More sharing options...
Tehnation Posted October 12, 2019 Share Posted October 12, 2019 https://legacygt.com/forums/showthread.php/top-feed-injector-plug-220861.html?t=220861&highlight=fuel+rail This is what I did. I paid like 80-90 bucks for a 07+ fuel rail from the junkyard. My total was $795 for 1000cc top feed/tgv delete/8mm spacer mods. Link to comment Share on other sites More sharing options...
shralp Posted October 12, 2019 Share Posted October 12, 2019 Also went to ‘07+ OEM fuel rails in my track car with IAG TGV deletes when I swapped out the VF52\DW 740’s for a custom 16G/1000cc inj. No issues and it runs great. Link to comment Share on other sites More sharing options...
Scottydunno Posted October 12, 2019 Author Share Posted October 12, 2019 https://legacygt.com/forums/showthread.php/top-feed-injector-plug-220861.html?t=220861&highlight=fuel+rail This is what I did. I paid like 80-90 bucks for a 07+ fuel rail from the junkyard. My total was $795 for 1000cc top feed/tgv delete/8mm spacer mods.I found and read your thread. Good stuff. Now if I use stock 07+ LGT or even 11-14 WRX injectors, do I have to retune? Scotty Link to comment Share on other sites More sharing options...
Tehnation Posted October 12, 2019 Share Posted October 12, 2019 Most likely yes! Link to comment Share on other sites More sharing options...
Nonamedude Posted October 13, 2019 Share Posted October 13, 2019 The stock top feeds for 07+ have a slightly different flow rate. Like 30cc higher. Not sure how much a difference that would be, but it's a thing. Link to comment Share on other sites More sharing options...
Scottydunno Posted October 13, 2019 Author Share Posted October 13, 2019 Thanx everyone. Looks like shopping, accumulating parts, and tuning will be in my future. Thanx again! Scotty Link to comment Share on other sites More sharing options...
awfulwaffle Posted November 4, 2019 Share Posted November 4, 2019 (edited) https://legacygt.com/forums/showthread.php/not-do-topfeed-conversion-280897.html Probably shouldn't use 06-07 WRX rails Edited November 27, 2019 by awfulwaffle Fixed link Link to comment Share on other sites More sharing options...
05RedGTWagon Posted November 27, 2019 Share Posted November 27, 2019 I used 07 wrx rails and FPR, with rubber fuel hose bridging the rails. I have a shot of it in post 2 here: https://legacygt.com/forums/showthread.php/build-thread-time-280134.html If I had to do it again, I'd use 08-14 WRX/STI, or 07-09 LGT rails/FPR. Reasons being, FPR sits on the driver side of the engine, and the line ends should actually bolt up to stock manifold points. I used IAG TGV deletes because my schedule got accelerated, but any factory top feed TGVs will work. If you're interested, I have mostly complete top feed deletes from an 06 WRX. Just need the gasket surfaces sanded. Is your setup in parallel or series? Do you have an studder/sumble in the 2-3k range? Link to comment Share on other sites More sharing options...
awfulwaffle Posted November 27, 2019 Share Posted November 27, 2019 Is your setup in parallel or series? Do you have an studder/sumble in the 2-3k range? Series. Stutter was pretty pronounced on the 06 WRX rails. Barely noticeable after going to 09 LGT rails. Link to comment Share on other sites More sharing options...
05RedGTWagon Posted November 27, 2019 Share Posted November 27, 2019 Series. Stutter was pretty pronounced on the 06 WRX rails. Barely noticeable after going to 09 LGT rails. Interesting! Both were using the same FPR and rubber hose setup between rails? Link to comment Share on other sites More sharing options...
awfulwaffle Posted November 27, 2019 Share Posted November 27, 2019 (edited) Interesting! Both were using the same FPR and rubber hose setup between rails? Nope, the 06 WRX has the FPR mounted right on top of the #1 injector, the topfeed LGT has it mounted away from the rails, right at the fuel return port that the rubber lines connect to. LGT rails also didn't have a rubber jumper hose between them - I can't decouple the effect of the rubber lines versus hardlines connecting the rails. However, the rubber lines were secured to a PCV hardline under the manifold when installed with plenty of zip ties, so it wasn't exactly flopping around. That thread I linked a few posts above has some videos of the pressure fluctuation change between the two setups. You can actually see the little bit of pressure pulsation that remains after I got the LGT rails, right around the RPM range where the tiniest hint of the stutter still exists. Edited November 27, 2019 by awfulwaffle Link to comment Share on other sites More sharing options...
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