Scooby2.5 Posted October 23, 2013 Share Posted October 23, 2013 updated wiring diagram with changes incorporated. Thanks everyone for the input on this. Lmk if we need to fix anything else. Can create alternative solutions as well, just let me know what you want/need. impressive!!!! Love it! Link to comment Share on other sites More sharing options...
SBT Posted October 23, 2013 Share Posted October 23, 2013 (edited) Yea I understand the math BUT, 10ga massive wire into the connector pins, through the fuel pump rubber plug etc etc is not worth .2 volts. I am not sure you would even see that much drop on an actual meter. If you want to pick up a few more tenths of a volt do the diode mod. 13.8 is low for a alternator anyway hence the reason the toyota guys came up with the HBK fuse. If you have a Braille battery like I do, 13.8 isn't even enough to charge it well according to the Braille specs. I used 12ga throughout my whole modification. I'm confident I can get everything I need from the 12ga setup. AFWIW, the DW wires (15' of Red +12V Battery Lead, 5' of Black -12V wire, and all four of the Automotive Relay pigtails are 12ga.). This and uprated voltage from the alternator, I should be good to go all the way up the power/torque tree. What is this HBK fuse of which you speak? Edited October 23, 2013 by SBT - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
Scooby2.5 Posted October 23, 2013 Share Posted October 23, 2013 Ooops MK3 from HKB, the diode fuse. By the way it is expensive but if you factor in all they did to get it made and where it has to ship from its not too bad. Plus its a resetable un-blowable fuse. It will last forever. Link to comment Share on other sites More sharing options...
SBT Posted October 23, 2013 Share Posted October 23, 2013 Yeah - that latter bit appeals to my sense of "worry-not" about out-of-sight stuff. - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
Th3Franz Posted October 23, 2013 Share Posted October 23, 2013 Very nice SBT. Using your diagram for a quick reference when I do my install tonight -Franz The end of a Legacy http://www.youtube.com/th3franz Link to comment Share on other sites More sharing options...
Turkeylord Posted October 23, 2013 Author Share Posted October 23, 2013 (edited) I'm cool if we want to call out 12ga in the diagram. It's what most will use, especially if they are going straight to the pins. I've got a couple posts up front to work with, I'd like to convert one to a "Variations" post. Help me with the list fellas. Comments in italics. 1. FPCM upgrade - I still think this could be considered optional, I saw a massive improvement even with the stock module. a. 22750AA010 Module - Performs better than stock LGT module (22648AA081) - Have we quantified this yet? I can when I get mine... b. 22648AA140 Module - Performs better than stock LGT module (22648AA081) - Have we quantified this yet? 2. Wire directly to connector pins a. New pins from Sumitomo - for fuel pump housing plug (pin removal instructions) b. 81803FG010 12ga Pigtail - for FPCM plug c. Salvage OEM pins from existing connectors 3. Alternator sense wire diode mod a. HKB MK3 diode fuse or (DIY alternate) b. Diode spliced into alt sense wire Others? Edited October 25, 2013 by Turkeylord Link to comment Share on other sites More sharing options...
SBT Posted October 23, 2013 Share Posted October 23, 2013 Updated the walk-through PDF on ScoobyMods. Thanks for all the work running the individual pieces to ground and to Turkeylord and the rest of the team for documenting everything so well with photos and write-up. Wiring diagram, Build-sheet and Addendum info are all hyperlinked from Page 1 of the updated PDF. How-about putting the link to the PDF in your OP? - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
SBT Posted October 23, 2013 Share Posted October 23, 2013 Is 2b. long enough to use on our Legacy? - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
SBT Posted October 23, 2013 Share Posted October 23, 2013 Better link to 3b. is http://www.scoobymods.com/showthread...10547.html?amp - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
Turkeylord Posted October 23, 2013 Author Share Posted October 23, 2013 How-about putting the link to the PDF in your OP?Will do! Is 2b. long enough to use on our Legacy? No, I believe it's what I bought from KCwagon - short and has plugs on both ends. You would need to splice wires or salvage terminals. Keys for scale... http://i.imgur.com/VNmekzTl.jpg Someone please correct me if that's not right. Better link to 3b. is http://www.scoobymods.com/showthread.php/raise-your-alternator-voltage-10547.html?amp I saw that one, I just wish the pics weren't broken :\ It's better anyway though, will update. Link to comment Share on other sites More sharing options...
Turkeylord Posted October 23, 2013 Author Share Posted October 23, 2013 (edited) Th3Franz's pins are for the fuel pump housing plug only correct? Do we have a source for the FPCM pins? Edited October 23, 2013 by Turkeylord Link to comment Share on other sites More sharing options...
Th3Franz Posted October 23, 2013 Share Posted October 23, 2013 Fuel Pump plug only. I didn't look into the FPCM pins, since they need to be spliced/tee'd anyway. Correct me if I'm wrong, but you still want +batt power to the FPCM for proper PWM manipulation of the ground wire. -Franz The end of a Legacy http://www.youtube.com/th3franz Link to comment Share on other sites More sharing options...
SBT Posted October 23, 2013 Share Posted October 23, 2013 This was my concern as well, otherwise the FPCM is "neutered". Believe that B+ is where the relay power (from the stock FP Relay) comes in so it looks, as least on paper, that the FPCM still has +12V from that source. Am I missing anything? Will attempt a re-perusal of the wiring diagrams posted earlier in the other thread to see if I can identify the specific FPCM pin-outs. If someone has the time to do this, it may be a while before I can get to it. - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
SBT Posted October 24, 2013 Share Posted October 24, 2013 Forester blogger's Alternator Diode fix - nicely done. Much more involved, and one of the reasons that the HBK PTC MK3 Diode/Fuse costs what it does. - Pro amore Dei et patriam et populum - Link to comment Share on other sites More sharing options...
BoozeRS05 Posted October 24, 2013 Share Posted October 24, 2013 Is there a complete plug and play kit that will give me most of the results you guys are discussing here? EB's Subaru journal - 2005 LegacyGT Wagon & 2014 Forester FB25 (2008 specB - RIP) IG@legacygtliving Link to comment Share on other sites More sharing options...
Turkeylord Posted October 24, 2013 Author Share Posted October 24, 2013 Fuel Pump plug only. I didn't look into the FPCM pins, since they need to be spliced/tee'd anyway. Correct me if I'm wrong, but you still want +batt power to the FPCM for proper PWM manipulation of the ground wire.True, the only one you'd replace would be the chassis ground I guess. This was my concern as well, otherwise the FPCM is "neutered". Believe that B+ is where the relay power (from the stock FP Relay) comes in so it looks, as least on paper, that the FPCM still has +12V from that source. Am I missing anything? Will attempt a re-perusal of the wiring diagrams posted earlier in the other thread to see if I can identify the specific FPCM pin-outs. If someone has the time to do this, it may be a while before I can get to it.Is this what you're looking for? http://i.imgur.com/LchaANXl.jpg Forester blogger's Alternator Diode fix - nicely done. Much more involved, and one of the reasons that the HBK PTC MK3 Diode/Fuse costs what it does. That's a good DIY HKB alternative, but it doesn't have to be that complicated. Cut sense wire, solder in diode, heat shrink. I'll list that option though. Is there a complete plug and play kit that will give me most of the results you guys are discussing here? Not plug and play, no. You'd have to make Y harnesses for both ends, etc etc.. The DW kit is as close as it's gonna get probably. Link to comment Share on other sites More sharing options...
Th3Franz Posted October 24, 2013 Share Posted October 24, 2013 I installed my fuel pump hard wire tonight and ran the car. The new pins fit in the stock fuel pump harness. 12 awg wire is a good fit for the pins I posted. The seals were a tight fit though and I also had to trim a little bit of the white plastic piece that goes on the plug to properly recess in place. I didn't upgrade earth wire from the FPCM just yet. Going to measure the voltage tomorrow. I'll upload a couple pics once I clean it up a little better. Just wanted to get the connections and test done. -Franz The end of a Legacy http://www.youtube.com/th3franz Link to comment Share on other sites More sharing options...
Scooby2.5 Posted October 25, 2013 Share Posted October 25, 2013 I'm cool if we want to call out 12ga in the diagram. It's what most will use, especially if they are going straight to the pins. I've got a couple posts up front to work with, I'd like to convert one to a "Variations" post. Help me with the list fellas. Comments in italics. 1. FPCM upgrade - I still think this could be considered optional, I saw a massive improvement even with the stock module. a. 22750AA010 Module - Performs better than stock LGT module (22648AA081) - Have we quantified this yet? I can when I get mine... b. 22648AA140 Module - Performs better than stock LGT module (22648AA081) - Have we quantified this yet? 2. Wire directly to connector pins a. New pins from Sumitomo - for fuel pump housing plug b. 81803FG010 12ga Pigtail - for FPCM plug c. Salvage OEM pins from existing connectors 3. Alternator sense wire diode mod a. HKB MK3 diode fuse or (DIY alternate) b. Diode spliced into alt sense wire Others? Calvin Dotson (Cobb Plano Tuner) and I quantified the difference between the two modules. I think I reposted it earlier in this thread. I'm running around for work today so I can't look but if someone has time and can look in this thread or the original thread and repost that would be great. I think in the other thread it's in the first few pages. Link to comment Share on other sites More sharing options...
Scooby2.5 Posted October 25, 2013 Share Posted October 25, 2013 Fuel Pump plug only. I didn't look into the FPCM pins, since they need to be spliced/tee'd anyway. Correct me if I'm wrong, but you still want +batt power to the FPCM for proper PWM manipulation of the ground wire. Yes this is correct. It would be nice to have the pins for this though. You could crimp your splice right to the pin. I think I did that I'd I remember correctly. I was cannibalizing pins from a spare STI pigtail like the one in the picture above with the keys Link to comment Share on other sites More sharing options...
Scooby2.5 Posted October 25, 2013 Share Posted October 25, 2013 This was my concern as well, otherwise the FPCM is "neutered". Believe that B+ is where the relay power (from the stock FP Relay) comes in so it looks, as least on paper, that the FPCM still has +12V from that source. Am I missing anything? Will attempt a re-perusal of the wiring diagrams posted earlier in the other thread to see if I can identify the specific FPCM pin-outs. If someone has the time to do this, it may be a while before I can get to it. Check the initial thread I think all this data is in there with factory wiring diagrams and everything. Link to comment Share on other sites More sharing options...
Scooby2.5 Posted October 25, 2013 Share Posted October 25, 2013 Forester blogger's Alternator Diode fix - nicely done. Much more involved, and one of the reasons that the HBK PTC MK3 Diode/Fuse costs what it does. Yea I followed this thread to make my first one but just wanted something more clean. When I found out the MK3 was a resettable fuse I decide it was worth it. Very fine piece. If we could get some vendor on here to stock these and get a handful of them we might be able to cut the cost. Some of the expense is the crazy certified shipping from Australia Link to comment Share on other sites More sharing options...
Turkeylord Posted October 25, 2013 Author Share Posted October 25, 2013 Calvin Dotson (Cobb Plano Tuner) and I quantified the difference between the two modules. I think I reposted it earlier in this thread. I'm running around for work today so I can't look but if someone has time and can look in this thread or the original thread and repost that would be great. I think in the other thread it's in the first few pages.I found this one the other day while searching for references to the FPCM part numbers... Well the verdict is the STI/Impreza fuel pump module was able to plug right into the LGT harness. Bad news is the module only output 11.9 volts. .2 more than the stock legacy module on the stock wiring harness. I'm not sure about this part as I'm getting 13.0 out of my stocker even with a lower 13.7v alternator output. If you bypass the wiring harness on the legacy module we would get 12.5 volts.I will verify when I get my STi module. Link to comment Share on other sites More sharing options...
Th3Franz Posted October 25, 2013 Share Posted October 25, 2013 My fuel pressure regulator gauge was bad. The old gauge was only reading 30 PSI. New gauge was showing a spike of 58 PSI fuel pressure at idle after doing this mod. Oops. Fixed that now and dropped the duty cycle. Much better! -Franz The end of a Legacy http://www.youtube.com/th3franz Link to comment Share on other sites More sharing options...
Turkeylord Posted October 25, 2013 Author Share Posted October 25, 2013 (edited) Found one more FPCM A/B comparison... I have it broken down progressively from stock to where I am at now. All reading were taken at the pump with the same volt meter at 100% pump duty cycle STOCK - 11.5 volts STI FPCM - 11.8 volts STI FPCM, 12g power to pump - 12.7 volts STI FPCM, 12g power to pump, 12g ground to FPCM - 13.2 voltsOr this one, finding 11.6v stock... Before I started messing with mine, I was seeing about 11.6 volts to the fuel pump at 100% duty cycle. As I started changing things, Scooby2.5 and I measured the differences in configurations. Here is a brief synopsis: All measurements are at start-up w/ 100% Fuel Pump Duty Cycle 11.6 volts - 100% factory wiring,stock FPCM, DW 65c 11.8 volts - 100% factory wiring,STI FPCM, DW 65c 12.6 volts - Upgraded wiring, utilizing the STI FPCM, DW65c 13.8 volts - Upgraded wiring, battery power to pump, DW 65cSo Shawn picked up .2V to .3V but again that was with stock wiring like Scooby2.5's results. I'll see what the differences are for both modules on the upgraded wiring when I get mine. I swear there was one more set of measurements somewhere else - someone was getting 14v, but maybe that was the alternator reading - I just can't find it Edited October 25, 2013 by Turkeylord Link to comment Share on other sites More sharing options...
Scooby2.5 Posted October 26, 2013 Share Posted October 26, 2013 Found one more FPCM A/B comparison... Or this one, finding 11.6v stock... So Shawn picked up .2V to .3V but again that was with stock wiring like Scooby2.5's results. I'll see what the differences are for both modules on the upgraded wiring when I get mine. I swear there was one more set of measurements somewhere else - someone was getting 14v, but maybe that was the alternator reading - I just can't find it I think it was coldscooby (sp). He had an alternator with higher output. Shawn changed his alternator as well at some point and it put out 14.2 Another factor is using a meter. A PWMS needs to be looked at with a scope With the meter, test it by checking it from pos on pump and then to chassis ground. See what voltage is actually at the pump. Then check it from pos on the pump and on neg (PWM) coming from the module. This reading will be an AVERAGE reading unless you look at it with an O scope Find the thread on NASIOC, we posted a link to it in the other thread. It actually showed some scope readings and what the neg lead waveform looked like. It seems that with good voltage going to the module we saw about .5 to .7 more out of the STI module than the the legacy module. It was way more expensive as well in the 04-07 years Just remember though depending how good your meter is etc it's averaging the reading to "ground" because of the PWM signal it sees on the neg lead from the module. Its sort of a floating ground I'm going to get my O scope out one if these days and take a look at it myself Link to comment Share on other sites More sharing options...
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