archemitis Posted March 4, 2004 Share Posted March 4, 2004 ok, i got fire in the holes. finaly got my ea82 mpfi on the way to working, in my ea81 hatch. so i got a couple questions. i have heard some people using a tank of some sort under the hood, with the fuel pump there, so you dont have to run efi lines all the way from the tank. what have people used? i tried sometihing, but it seems dangerous to have a half gallon under the hood. my other idea is to use an inline efi pump, under the hood, fed by the stock 1.5 lb carb pump. anybody got any pics of a successful install? i can post a pic of my car with the computer sitting on the hood=] Link to comment Share on other sites More sharing options...
MilesFox Posted March 4, 2004 Share Posted March 4, 2004 i know that cis subaru used his stock pump(spfi) to feed the underhood bosch pump, 80 psi i myself plan to use the carb pump in my wagon to feed the legacy pump under the hood for the ej22 dont know for sure how i will work out, but its nothing to stop me from trying it out. besides, trying things out is how we as a message board knows things when it comes to new ideas Link to comment Share on other sites More sharing options...
archemitis Posted March 4, 2004 Author Share Posted March 4, 2004 i should just order a fuel cell, are those legal inside a hatch? Link to comment Share on other sites More sharing options...
TomRhere Posted March 4, 2004 Share Posted March 4, 2004 1. What was the answer to this post, http://www.ultimatesubaru.org/usmb/forum/showthread.php?s=&threadid=12332 2. Been discussed on here before, about using carb fuel pump to supply MP/SP-FI pump mounted under hood. Not sure of the out-come of that discusion though. Link to comment Share on other sites More sharing options...
archemitis Posted March 4, 2004 Author Share Posted March 4, 2004 no answer at all. i got the injectors to open, and i got spark, so i guess you dont need a diode, or a resistor. after this thing is running around town for a couple days, i will try and post my revised engine wiring schematic. Link to comment Share on other sites More sharing options...
rallyruss Posted March 4, 2004 Share Posted March 4, 2004 why would it be difficult to put the pump in the same location as the stiock one? oh I see you are worried about fuel line differeces. the hard line will have no problem at all. if you want to be safe just change the flex hoses at the ends to efi rated line. I would still recomend putting the pump in the stock location. efi pumps espically push better than pull. thats why if you mount it up front you have to keep your stock pump. too many parts that can fail that way for my taste. yeah I know VWs and other cars did that in the PAST but not any more they got over that sillyness. It was inefficient and expensive to fix. compared to a single pump set up. I had a simillar issue when converting my pick up to EFI I put it as close to the tank as possible and ran high pressure hose to the stock hard line. mounting was a PITA there. yours should go smoothly. Link to comment Share on other sites More sharing options...
CIS Subaru Posted March 5, 2004 Share Posted March 5, 2004 If you want to put the EFI pump under the hood, I suggest getting a "surge tank" from a VW Fox. In the following picture, it is labled as a "fuel resevoir": http://usmb.net/repair/cis/Fuel%20Pump%20Assembly%20Diagram.JPG You would be connecting it just as the labels indicate. I tend to agree with the others here that you might be best off just putting the EFI pump in place of the original one. Subaru MPFI doesn't run anywhere close to the 80psi that CIS uses, so you should be fine if you just replace the rubber sections with fuel-injection hose from a parts store. Either way should work fine, so it's really just a question of which one seems best to you. Link to comment Share on other sites More sharing options...
archemitis Posted March 5, 2004 Author Share Posted March 5, 2004 well, i found the universtal pump that fits on some sort of ford, its 80 bucks if i but it at napa, with my account, and it looks realy sanitary, andi might go with that. if i start getting fuel problems, i will look at a surge tank, seems like a good plan, but i wanna drive, it snowed today =]. Link to comment Share on other sites More sharing options...
archemitis Posted March 7, 2004 Author Share Posted March 7, 2004 heres my setup now Link to comment Share on other sites More sharing options...
archemitis Posted March 7, 2004 Author Share Posted March 7, 2004 its a ford fuel pump that flows 50 gph, and pumps up to 90 lbs. and it only cost 39 bucks, compared to the 100-140 bucks i was finding them for. took the partsdork forever to find it, heres the part number 2p74028 its a tru-flow, and its in a napa box. it came in raw metal color, i had to paint it, and mount it on a coil bracket. should work good. Link to comment Share on other sites More sharing options...
archemitis Posted March 10, 2004 Author Share Posted March 10, 2004 if this pump pumps up to 90 lbs, is my stock return line gonna get overfilled, and pressurised? Link to comment Share on other sites More sharing options...
rallyruss Posted March 10, 2004 Share Posted March 10, 2004 up to 90 psi. is not an issue. the gph is what you are thinking of. I seriously dont think that will be an issue. there should be no pressure on a retun line. if there is it means the line is restricted. so how are you powering that pump? I assume the stock pump is still in line. Link to comment Share on other sites More sharing options...
Adam N.D.J. Posted March 10, 2004 Share Posted March 10, 2004 You guys are kinda on the right track, but for the most part way off. You shouldn't cut corners on stuff like this. Granted, it may have worked for some people along the way, but doing it the right way is a much better idea. First pull out the drivers seat (and rear seat is you have one), pull the carpet away from the side, there will be the stock fuel lines right there. Then whot you do is go down and buy 8 feet of aluminum 3/8's hardline, get this from any parts store. The stuff is actually pretty flexable, and you can get cheap bending tools for it too. Then just start going through the grommet in the fire wall from the engine compartment to the drivers compartment, push in the new hardline. Pull it down from the dash, then pull it through untill you have enough to go out the hole towards the tank and pump. Onces you have the line coming in and going out, start shaping it to match the stock hardline, and zip tie it to the stock line as you go. Then just replace the interior stuff and your good to go. It took me about 30 the first time I did it, now I can do it in about 15. Now that you have the new feedline, you just use the old feedline as the new return line. Replace the old rubber on the you "new return" with FI rated hose, and use FI hose on the new feed connections, and it will handle up to 90psi with no problems. You will also have to consider the tank. The stock output on the tank will not feed a FI pump very well, as most FI pump have at least a 1/2 input and 3/8 output, and the carb'd tanks outputs are normally 3/8's. You have fix this in two ways, get an FI tank, (my route), or you can go down to you local hardware supply store, get a brass fitting with a 1/2" nipple on it, and fine thread couple. Drill a hole in the bottom side of the tank faceing the pump slightly smaller than the brass coupleing, be carefull, and use lots of cutting lubricant on the drill bit to avoid overheating it (BOOM). Then just put some teflon tape on the threads of the fitting, and start running it in there. The two that I've done this too (as temp means while searching for an FI tank) worked just fine and didn't leak. You can then use any 1/2" fuel grade rubber hose to connect the tank to the pump. Hope this helps everyone out. Link to comment Share on other sites More sharing options...
CIS Subaru Posted March 10, 2004 Share Posted March 10, 2004 That seems like excellent advice, Adam. I had already planned to replace the hard lines for my next CIS project since I'll need them both to be entirely on the passenger side. I'm going for a more "factory" look this time, so I'll be putting the fuel pump under the car where it belongs. I was also concerned about the outlet size of the carbed tank. I'm putting this into an EA81 Hatchback, so a FI tank is not an option. A surge tank would fix this, since it reduces fuel flow in/out of the main tank, but I doubt I'll have room for one under the car. So your idea for an enlarged output sounds pretty good. Link to comment Share on other sites More sharing options...
archemitis Posted March 10, 2004 Author Share Posted March 10, 2004 so exactly what is my broblem? my 4 runner sitting right next to the car has hard lines for the efi that are the same size as my ea81 hatch. just wondering why i would ever need a half inch pipe to feed fuel? just wondering, im not changing it now. Link to comment Share on other sites More sharing options...
Subafreak Posted March 11, 2004 Share Posted March 11, 2004 I just used the stock line when I did the EFI in my 81 wagon and didn't have any problems. I just mounted the stock EA82 pump in the stock location and all was good. I don't see why anyone would get all crazy with extra tanks and new lines. Link to comment Share on other sites More sharing options...
CIS Subaru Posted March 11, 2004 Share Posted March 11, 2004 For safety's sake, I'd replace the rubber hose sections with the stronger FI hose. I also agree that your stock hard lines should be fine. As stated above, I'll be using new hard lines in my project because I need them to go a different route, and be able to handle a constant 80-90 psi. Link to comment Share on other sites More sharing options...
archemitis Posted March 11, 2004 Author Share Posted March 11, 2004 cool, 80-90 constant is alot. you could push lotsa lbs of boost with a system like that, i would guess. Link to comment Share on other sites More sharing options...
archemitis Posted March 16, 2004 Author Share Posted March 16, 2004 so i changed the title, i found out exaclty what was wrong with the system i was trying to use. the carb pump couldnt keep up for one reason or another, and i kept runing out of fuel, while trying to start it, not even runing. so i stuck the fuel pump back where the stock pump goes, and it works good now, 80-90 lbs runing through stock hard fuel lines, and i replaced the rubber lines with efi ones. it realy wasnt any harder than puting it under the car, so dont do what i did =] Link to comment Share on other sites More sharing options...
CIS Subaru Posted March 17, 2004 Share Posted March 17, 2004 I'm not sure, but I think your system only puts out something like 35-40psi. The Bosch K-Jetronic system (CIS) that I used on my EA82 Wagon uses 80-90psi. Glad to hear that you got it working. The problem you discovered is exacly the reason why you NEED to use a surge tank when using two pumps with different flow characteristics. Link to comment Share on other sites More sharing options...
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