Z31TURBODRAY Posted January 7, 2011 Share Posted January 7, 2011 yes I searched!! I will be puttin a l28et in a 240z or 260z soon, would I run fuel lines and an inline fuel pump and be ok just to get it running? or how would I do this? because I know the 240z is carb but im not sure about the 260z thanks. Quote Link to comment Share on other sites More sharing options...
skib Posted January 7, 2011 Share Posted January 7, 2011 use a 75/76 tank, remove the old return line, run a new feed line and use the old feed as a return, hook up an inline pump. if its a 73/74 it should have a small electric pump in the back along with the mechanical. on my 73 I just replaced it with a supra TT pump and it was good, just plugged it into the old pumps wiring. Quote Link to comment Share on other sites More sharing options...
ben280zx Posted January 7, 2011 Share Posted January 7, 2011 (edited) Or you can grab all the feed and return lines from 75-78 and work with that. You can also get a external fuel pump from 280zxt. Edited January 7, 2011 by ben280zx Quote Link to comment Share on other sites More sharing options...
Nigel Posted January 7, 2011 Share Posted January 7, 2011 (edited) yes I searched!! I will be puttin a l28et in a 240z or 260z soon, would I run fuel lines and an inline fuel pump and be ok just to get it running? or how would I do this? because I know the 240z is carb but im not sure about the 260z thanks. Where and what were you searching for? There have been countless discussions on fuel system mods needed to run FI in 240Z's. That being said, at the very least, you will need a larger return line of at least 5/16", and if you ever plan on tracking the car, I wouldn't waste my time on the 280Z tank. With a high flow pump, it'll be sucking air on hard corners with less than half a tank. There are lots of discussions on better alternatives (sumps, surge tanks, in-tank pumps, custom tanks, fuel cells). If you're just looking for something temporary to get the car driveable, use a 90deg fitting off of the drain on the bottom of the tank as the supply, and use the original feed as the return with a new, bigger feed line. Nigel '73 240ZT Edited January 7, 2011 by Nigel Quote Link to comment Share on other sites More sharing options...
Pyro Posted January 7, 2011 Share Posted January 7, 2011 never done it, but read the stock 240 return line will work as a return line for a stock efi pump. It would be worth a try. Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 7, 2011 Share Posted January 7, 2011 never done it, but read the stock 240 return line will work as a return line for a stock efi pump. It would be worth a try. Remove this post, it's not speaking from experience and is repeating bad, inaccurate information. The stock L28ET pump running to a stock L28ET and trying to run bypass through the 3/16" stock 240Z return line will moreoften than not chug pig rich at any speed near idle. This goes the same for an EFI N/A conversion as well. There just is not enough flow capacity in the line to accomodate the FPR bypass under those conditions. This is out there COUNTLESS times. The preferred workaround is to use the EVAP line from the crankcase accumulation and use it as your FPR return line. You can even run the line off the manifold straight to the line on the left innerfenderwell. You will need to vent the tank another way, but this is all covered in the archives. Quote Link to comment Share on other sites More sharing options...
Pyro Posted January 7, 2011 Share Posted January 7, 2011 Off your meds again it seems. never said it would work for sure. Just said it would be worth a try. your statement "more often than not", also states it may work. I say, install the pump, return the fuel with the stock line and see what the return pressure is before swapping tanks and running new lines (as recommend above) Looping the fuel back on a 5/16 line generates less than 1 psi of back pressure (i do know that from experience), maybe a 3/16 could be as low as 5 or 10. But as I said, I don't know because I haven't tried it, but still worth a try (even if I haven't personally tried it). The method you described also is worth a try. However, the return line pressure should always be measured when doing things like this. lines get clogged over the years. Quote Link to comment Share on other sites More sharing options...
z-ya Posted January 7, 2011 Share Posted January 7, 2011 Since 75-76 tanks are hard to come by in good shape (any S30 tank for that matter), I was thinking of this setup. You will need to fabricate or buy a suitable surge tank. Find a place to mount it at the rear of the car (along with two pumps) Connect like this with all 5/16" hoses and fittings: [240Z tank] -> [Filter] -> [Low pressure pump] -> [surge tank] -> [240Z tank] [surge tank] -> [EFI pump] -> [Filter] -> [stock 240Z 5/16" hard line] -> [fuel rail] -> [regulator] -> [surge tank] The only modification to the 240Z tank is to remove and drill out the stock return barb. I did this on my turbo car and soldered in a 3/6" barb. You could use some fuel proof epoxy or JB Weld or something so you don't have to put a flame to the tank. Basically if you drill and tap the plate where the return barb is to 1/4" NPT, you can screw a hose barb in there with some epoxy or something and it should hold just fine (no pressure). Use the stock 5/16" hard line, and leave the 3/16" one alone. Believe me, it is not fund removing and reinstalling those hard lines. The other option is to use the evap line as Tony suggested. If you use that, you can locate the surge tank and EFI pump in the engine compartment. In either case, you need to drill the stock return barb on the 240Z tank and replace it with 5/16" barb. Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 7, 2011 Share Posted January 7, 2011 My statement 'more often than not' refers to when it starts blubbering from bing pig rich---some it won't run AT ALL because it's so rich, others it won't idle below 1500 (sometimes fast idle, sometimes foot on the throttle) before it wetfouls the engine. Blub blub blub puffing smoke out the back of the tailpipe. I make this statement because every one I've ever done has done this. I've only READ of people who claim to be able to run it beloww 2000 rpms if it runs at all. The 240's fuel line is too small for a pump with proper capacity to run the car at idle AT ALL. I haven't seen one YET that idles with proper mixture with the 240 return line. Now, as someone admittedly who has never tried it, and only read about it... might I suggest you entertain the thought that you're wrong on this and giving out hearsay and poor information? It's exceedingly easy to try: go stick a 0.1875" restrictor in the line of a working EFI L-Engined car [at idle and watch what happens to the AFR's. Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 7, 2011 Share Posted January 7, 2011 In either case, you need to drill the stock return barb on the 240Z tank and replace it with 5/16" barb. Pete, might you elaborate for the doubting Thomas exactly why you need to drill the stock return barb on the 240 Tank to 5/16"? (I have always moved the return to the 1/4" vent line at the top of the tank personally.) Quote Link to comment Share on other sites More sharing options...
z-ya Posted January 7, 2011 Share Posted January 7, 2011 Pete, might you elaborate for the doubting Thomas exactly why you need to drill the stock return barb on the 240 Tank to 5/16"? (I have always moved the return to the 1/4" vent line at the top of the tank personally.) Cut off the 3/16" return barb and drill the plate for a 1/4" NPT tap, then tap it 1/4" NTP. The plate is not all that thick, but you can still screw a 1/4" NPT to 5/16" hose barb into the threaded hole. What I suggest is to either put some sort of fuel proof glue on the thread, or solder it to prevent any leakage. Quote Link to comment Share on other sites More sharing options...
CamH Posted January 8, 2011 Share Posted January 8, 2011 Remove this post, it's not speaking from experience and is repeating bad, inaccurate information. The stock L28ET pump running to a stock L28ET and trying to run bypass through the 3/16" stock 240Z return line will moreoften than not chug pig rich at any speed near idle. This goes the same for an EFI N/A conversion as well. There just is not enough flow capacity in the line to accomodate the FPR bypass under those conditions. This is out there COUNTLESS times. The preferred workaround is to use the EVAP line from the crankcase accumulation and use it as your FPR return line. You can even run the line off the manifold straight to the line on the left innerfenderwell. You will need to vent the tank another way, but this is all covered in the archives. This a thousand times. I spent weeks trying to get my Z running, only to figure out the problem was that I was using the stock 240Z return line. I put a fuel pressure gauge in line and saw that immediately after turning on the fuel pump, the gauge would max out. Switched to the evap line and the car fired right up and ran just fine. Use the evap line or run a new return. Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 8, 2011 Share Posted January 8, 2011 (edited) Well that was a neat something I didn't know I could do Pete, thanks for that. I was shooting more for a 'why' than a 'how' but CamH kinda did that number from firsthand experience in a way better than I could hope for! If you haven't done it, and only read about it, don't post it! Especially when someone (now several) who have done it inform you it's wrong. Hopefully someone reading the thread will read to the end to get the right information on what line size to use. It's sad when correction requests are ignored, it doesn't help the new guys actually seraching for good information. Thanks Pete, CamH! Edited January 8, 2011 by Tony D Quote Link to comment Share on other sites More sharing options...
Z31TURBODRAY Posted January 9, 2011 Author Share Posted January 9, 2011 ok thanks for all the answers! but to keep things simple lol take the 240z return line out, put the evap line in, connect the efi lines to the exsisting 240z carb lines and im done? So many people have done the swap that I wouldnt think its as hard as you guys are making it sound right.Thanks and ive done many swaps maybe I just need to get the damn car and look at what you guys are talkin about to make it not complicated like it sounds. Quote Link to comment Share on other sites More sharing options...
Z31TURBODRAY Posted January 9, 2011 Author Share Posted January 9, 2011 I would love to have some pics of these exact parts if one of you true z enthusiasts wants to go outside and take them?Im sure you guys dont have much better to do right? haha Quote Link to comment Share on other sites More sharing options...
CamH Posted January 9, 2011 Share Posted January 9, 2011 My Z is in storage until April, so no pictures, but the evap line is on the opposite side of the engine bay from the factory feed and return lines, in roughly the same location. You don't need to run any new lines for it, just run a hose from your fuel rail to it. Quote Link to comment Share on other sites More sharing options...
Z31TURBODRAY Posted January 9, 2011 Author Share Posted January 9, 2011 thanks cam you truly made my life easier with such a simple answer Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 9, 2011 Share Posted January 9, 2011 It's not hard, unless people who haven't done it weigh in with B.S. and clud the issue. The EVAP line already exists on the left fender well. This is all out there, if that kind of direction sounds 'hard' you may want to consider not doing the conversion until you learn a bit more about your car. An EFI conversion is very straightforward, the EFI is very simple. As long as you understand it, this is very simple and straightforward. If you don't then things can look insurmountable. Reading is your friend, this conversion is well documented in FAQ/Stickies take the time to read them. This answer is in there as well. Quote Link to comment Share on other sites More sharing options...
Z31TURBODRAY Posted January 10, 2011 Author Share Posted January 10, 2011 Its not hard at all, like I said ive done many swaps before the issue became clud like you said.I got a very straightforward answer from cam like I wanted so thank you. Quote Link to comment Share on other sites More sharing options...
ryan95i4 Posted May 17, 2012 Share Posted May 17, 2012 My Z is in storage until April, so no pictures, but the evap line is on the opposite side of the engine bay from the factory feed and return lines, in roughly the same location. You don't need to run any new lines for it, just run a hose from your fuel rail to it. Once you run the return line to the evap line, is there anything you need to do with the lines at the back of the car at the tank? I just swapped the fuel line from the stock return line to the evap line and could not get the car to start. Swapped the line back to the stock return line and car started, but of course fuel pressure was way to high (over 60psi at idle). Quote Link to comment Share on other sites More sharing options...
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