Tony D Posted December 31, 2008 Share Posted December 31, 2008 One other option would be to put the fuel distribution block in the center of hte manifold with the regulator attached there, and using that as a centralized return point for the fuel return line. This way the length of the lines to any individual injector could be minimized/equalized, and you would know liquid fuel would always be in the block, just a short distance from the injection point. It could look very Hilborn-Like set up that way as the return pellet housing and return lever could be on that block to make it 'look' mechanical. The thing that is in my mind is the length of the lines to the longest injector may result in a pressure drop during batch firing. The lines should all come from a suitably sized distribution block with an accumulator on it to minimise pulsations when the injector banks fire. JeffP has a nice example on his webpage. I didn't have any issues firing alternate pulse 550cc injectors through 1/4" dedicated lines, but then I only had two of 'em. Putting the lines higher -- say on the same plane as the valve cover mounting bolts -- would allow you to make some neat insulated line clamps. The heat transmitted by the metal standoffs bolted directly to the head in early cars is considerable. Much of the heat transmission to the fuel lines was eliminated by simply insulating the heat transfer point with some phenolic holders instead of brazed sheetmetal holders (it's one of the reasons why the OEM line holding apparatus was plastic lined...) Quote Link to comment Share on other sites More sharing options...
Nizm0Zed Posted December 31, 2008 Share Posted December 31, 2008 just throwing this out there, but technically you dont need a fuel return. look at any of the later model jeeps as a good example, i know the 2001+ grand cherokee's do it. in the tank, where the pump picks up the fuel, is a pressure reg, it regulates the line pressure, and dumps the rest into the tank. they were running reliably enough (jeep? reliable?) to deal with 45 degree celcius days here down under. i know there are some aftermarket ECU's that could regulate it, but im sorry, i dont know which ones. Quote Link to comment Share on other sites More sharing options...
Tombarace14 Posted December 31, 2008 Share Posted December 31, 2008 A return line and FPR is needed at the rail for consistant fuel pressure. For this reason alot of the 350z/g35 guys are running return systems for higher hp apps. Quote Link to comment Share on other sites More sharing options...
Nizm0Zed Posted January 1, 2009 Share Posted January 1, 2009 oh im not disagreeing with you at all, and if you want good performance, its the way to go. but if its just to look good, and run well enough to enjoy driving, then a non return system could be done. Quote Link to comment Share on other sites More sharing options...
Derek Posted January 1, 2009 Author Share Posted January 1, 2009 A central distribution block in between the manifolds would be cool but being as the lines are done I'll be sticking with what I have! I'll be using a fuel pressure regulator at the distribution block with a return line to the tank. Well I made some good progress today. All of the butterflies are installed, The return springs are installed, and the linkage is adjusted and installed. So technically speaking the MANIFOLD IS DONE!!! I think. I still have to put in the vacuum stuff but unfortunately my parts didn't arrive yesterday. But all of the main machine work and assembly is completed. I'm also about halfway through the surge tank. I'll finish it up in the morning and then jump on the vacuum log when it arrives in the afternoon. We're almost there! Derek Quote Link to comment Share on other sites More sharing options...
Xnke Posted January 1, 2009 Share Posted January 1, 2009 I do believe I'm gonna express mail you an eyeball with an electronic wireless optical nerve assembly on the back, just so i can see this thing. It's gotta be awesome! Quote Link to comment Share on other sites More sharing options...
Daeron Posted January 2, 2009 Share Posted January 2, 2009 I'm just grinning with anticipation and waiting patiently for photos. The thought that I might soon enough get to see and hear this thing in person at no expense or inconvenience to myself whatsoever blows my mind:D Quote Link to comment Share on other sites More sharing options...
Ferrariferg Posted January 2, 2009 Share Posted January 2, 2009 I can't wait to see these done. Too bad it wont be in person. Kyle Quote Link to comment Share on other sites More sharing options...
Pharaohabq Posted January 2, 2009 Share Posted January 2, 2009 just throwing this out there, but technically you dont need a fuel return.look at any of the later model jeeps as a good example, i know the 2001+ grand cherokee's do it. in the tank, where the pump picks up the fuel, is a pressure reg, it regulates the line pressure, and dumps the rest into the tank. they were running reliably enough (jeep? reliable?) to deal with 45 degree celcius days here down under. i know there are some aftermarket ECU's that could regulate it, but im sorry, i dont know which ones. Yeah, actually earlier jeeps didn't need a return line either. When I EFI'd my 87' I used a fuel tank from an 97, which has the internal regulated fuel pump. made it easy. For this project, he's using a return, which is fine it's really a matter of preference, n since I doubt he'll easilly find an intank pump to fit, it would be a lot more work not to use a return. Phar P.s: Derek, you're making us drool telling us it's so close, but not putting pictures up!!!! c'mon! Good deal getting the manifolds basically done! Congrats on that, you're so close, I can hardly wait to see your install day picts! shouldn't take too long, (depending on your extra cleanup work I suppose, gotta clean your engine if I remember correctly) Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 2, 2009 Share Posted January 2, 2009 A return line and FPR is needed at the rail for consistant fuel pressure. For this reason alot of the 350z/g35 guys are running return systems for higher hp apps. This is incorrect. A non-return fuel system is available in most new vehicles as part of Federal Evaporative Emissions Requirements. Without using a return line, the fuel in the tank stays MUCH cooler, and therefore decreases fuel offgassing. A variable speed pump and fuel pressure transducer is all that is required to have consistent fuel pressures for a non-return fuel injection system. Matter of fact there are aftermarket kits out there now that incorporate PWM Control of the fuel pump through the ECM to do just that. BOSS Fuel Injection has PWM controllers that will run up to 500HP through their ECM. After that point, you must use a return line, simply because the amperage required to control that size fuel pump can not be accomodate within the confines of their small ECM control box. The reason G35 Guys are switching over to other regulators/return lines is for similar reasons---the existing controller and pump will not support the horsepower, not because the inherent design of the fuel delivery system is flawed (non returnless). The key point is to remember that the fuel boils because of heat soak AFTER the car is shut off. Realistically, if you have a problem with the setup you make, simply raise the fuel pressure from 3 bar to 4 bar (around 60 psi instead of 45) static and that shold raise the pressure boiling point more than enough to solve the problem. I'm amazed I didn't remember this from my own issues. I ran 4 Bar initially because I thought my injectors may need to be larger (I originally set up twin 270cc Turbo Injectors and was running lean on the dyno at 100hp, so I changed to 550's and went back to stock EFI pressure of 36psi static and occasionally had some soak restart issues until I bypassed the 3 sec timer on MS to run the pump longer.) I just put two and two together and realized that the decrease in static rail pressure (I was feeding injectors UNDER the SU's near the exhaust...) could account for the problem I was having with the 550's which didn't happen with the 270's at higher pressure! I'd say bump your fuel pressure and compensate by 'increasing' the size of your injectors in the MS program to accomodate the increased flow at 45psi -vs- 60psi (or whatever) and you sohuld be fine. In other words, run it with what you have, and if you have a problem FIRST try to increase the fuel pressure to 60 psi and see if that cures the issue. If not, then return lines or other methods for gietting cooling flow to the injector pintle fuel line may be required. Quote Link to comment Share on other sites More sharing options...
Derek Posted January 3, 2009 Author Share Posted January 3, 2009 P.s: Derek, you're making us drool telling us it's so close, but not putting pictures up!!!! c'mon! Good deal getting the manifolds basically done! Congrats on that, you're so close, I can hardly wait to see your install day picts! shouldn't take too long, (depending on your extra cleanup work I suppose, gotta clean your engine if I remember correctly) Hi Phar Well it really looks the same as in post #226 except the butterflies are in and there's springs on the bottom of the shafts. Install is going to take longer than projected. The only way to do the heat shield is remove the header from my car and mount it on to my mock up head with the manifold. Then I can accurately fabricate the heat shield. Also I'm not going to put much time in cleaning the engine compartment as I have to pull the head eventually so I'll just wait for that. I have a major list of things I need to do on the car at the same time so the cars going to be off the road for a few weeks. And work and reality just got in the way. I pretty much chewed up all my allotted time and then some! I need to kick out a few patterns and then I can get back on it. Probably going to be the third week of January before I can install the manifold. Sigh....... At least with the throttle springs on I can periodically walk by, snap the throttles and go "woomba woomba". Hey it's all I got right now! In other words, run it with what you have, and if you have a problem FIRST try to increase the fuel pressure to 60 psi and see if that cures the issue. If not, then return lines or other methods for gietting cooling flow to the injector pintle fuel line may be required. Good info an good advice! Fortunately it will be cool here for a few more months so I won't have to deal with it right away. Seriously my SU's are such crap none of these problems are going to be any worse than I'm dealing with right now. Derek Quote Link to comment Share on other sites More sharing options...
Daeron Posted January 3, 2009 Share Posted January 3, 2009 Ladies and Gentlemen!!!!!!!! *drumrollllll* I Give You.... *Trumpet*Fanfare* THE HYBRIDZ QUOTE OF THE DAY!!!!!!!! At least with the throttle springs on I can periodically walk by, snap the throttles and go "woomba woomba". Hey it's all I got right now! :ass: Quote Link to comment Share on other sites More sharing options...
Soundmasterg Posted January 3, 2009 Share Posted January 3, 2009 Derek, Hope you can video it and you tube it when you run it the first time with that manifold on there. Its gonna be sweet! Greg Quote Link to comment Share on other sites More sharing options...
Drax240z Posted January 3, 2009 Share Posted January 3, 2009 Isn't hypothetical theorizing SEVERELY frowned upon at this forum?Especially when NOT backed up by CONCRETE facts? Your ego, tone, and attitude are rather amusing, in all reality. YA MIGHT wish to put your feet back on the ground. Not every post on hybridz need to be based on fact, direct experience, or something underway. If that were the case we would be stifling innovation here, and innovation is something that this site promotes whole heartily. When it comes to people with years and years of experience in the automotive world, and specifically with Z's, their experience does give them some ability to theorize accurately about the subject matter without having actually done the work themselves. "Knowledge" I believe it's called. Once you spend some time on this site reading, rather than spouting off about nothing, you'll realize there is a large group of members here who have a staggering amount of experience with all facets of car building. TonyD is certainly someone I would consider to fit into that group, and he shouldn't need to post his qualifications to make such statements each and every time, instead it should be up to you. Before you get on your high horse and flame a long standing member, you'd be wise to check a little of their history out on this board, and educate yourself with their postings demonstrating their good judgement, sound reasoning and extensive experience. Be thankful I'm not an admin here. I would advise that you take a cool-it pill and try reading rather than posting for a while however. ----------------------------- Let's go back to Derek's super-duper work, shall we? Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted January 3, 2009 Administrators Share Posted January 3, 2009 Put the squirt guns away guy's. Quote Link to comment Share on other sites More sharing options...
josh817 Posted January 3, 2009 Share Posted January 3, 2009 As you can see Derek, you are almost up there with my daddy. The reason why you are not passed him is because he is my daddy and he's pretty cool. Does a lot of cool stuff yah know... However he hasn't built his own EFI system which was the real boost for you, otherwise such high approval ratings would not be possible.Also, DragonFly would be passed you, after all, he did balance his valve train. Daeron, you're up there because you helped me through my stroker build. TonyD, you're up with the big dogs too because you are the king of big dogs. Don't have any hard feelings about people beating you, just remember that I still love you. I tried to make a MAP 3D graph thing in Excell but I failed big time, couldn't figure out what my third axis should be... I did however make my Love Graph kind of 3D here. I also added the minor axis lines for you accurate people. You're doing awesome Derek! Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 4, 2009 Share Posted January 4, 2009 You forgot "love thy administrator" in your 3-d graph!!!! That is strike one. Oh, and you only get 2 strikes, this isn't baseball! Quote Link to comment Share on other sites More sharing options...
josh817 Posted January 4, 2009 Share Posted January 4, 2009 You forgot "love thy administrator" in your 3-d graph!!!! That is strike one. Oh, and you only get 2 strikes, this isn't baseball! Administration love is a given. Quote Link to comment Share on other sites More sharing options...
Derek Posted January 4, 2009 Author Share Posted January 4, 2009 As you can see Derek, you are almost up there with my daddy. The reason why you are not passed him is because he is my daddy and he's pretty cool. Does a lot of cool stuff yah know... However he hasn't built his own EFI system which was the real boost for you, otherwise such high approval ratings would not be possible.Also, DragonFly would be passed you, after all, he did balance his valve train. Daeron, you're up there because you helped me through my stroker build. TonyD, you're up with the big dogs too because you are the king of big dogs. Don't have any hard feelings about people beating you, just remember that I still love you. You're doing awesome Derek! Josh you crack me up! It will be interesting to see the graph after I post a video of it running. Derek Quote Link to comment Share on other sites More sharing options...
Derek Posted January 4, 2009 Author Share Posted January 4, 2009 Ok I went back and re-read every single post on this build. One thing that jumped out at me was that I may be screwing up with the way I'm introducing idle control vacuum. As it's designed right now I'm just dumping it into the balance tube at the end of #6 runner. I'm starting to think this may be a mistake as this will cause #6 to run lean. Would a better solution be to run 6 individual lines to each runner to introduce the vacuum. I haven't machined the log yet so this would not be a big problem to do Any thoughts on this Thanks Derek Quote Link to comment Share on other sites More sharing options...
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