cygnusx1 Posted April 2, 2007 Share Posted April 2, 2007 I am in the planning stages of the MS-II, Bosch 42# injectors, and JSK-O-ring rail. I am going to plumb the rail as a dead end rail as BRAAAP suggests will work fine. I am also going to use the stock ZXT regulator. The fuel tubing in the 280Z is very close to "5/16" to -6 AN compression adapter" so I will be using Tube-AN adapters like this: I am going to plumb the fuel supply tube from the tank into a "Tee". One leg of the "Tee" will go directly to the fuel rail. The other leg will be a fuel return and go to the regulator "in". The regulator "out" will go to the tank return line. The regulator will monitor manifold pressure with a vacuum hose. All braided lines will be terminated with these: or It's all going to be -6 size. A pressure gauge will be mounted on the end of the fuel rail near the firewall. I bought the stuff from: http://www.anplumbing.com/shop/ IN | | "T" ------->RAIL>Gauge | | Regulator | | tank Quote Link to comment Share on other sites More sharing options...
ktm Posted April 2, 2007 Share Posted April 2, 2007 Just a quick question, if you are going to use the stock FPR, why dead head it? You are still using the return, just relocating it from the rail to the T (so its not a true dead head setup). Is this to clean up the engine bay a bit? Quote Link to comment Share on other sites More sharing options...
aarang Posted April 2, 2007 Share Posted April 2, 2007 I can't remember what size fuel lines are in the S30, but in the 280ZXT the lines are 5/16", which is an AN 5, not an AN 6. If you want to plumb into the stock lines, you can get flare nuts and sleeves for an AN 5 to use on the stock lines. You will need a 37 degree flare tool. After flaring the stock lines, get an AN 5 to AN 6 adapter and run the AN 6 lines as needed. Summit sells everything you need. A flared tubing connection is alot better than the compression fittings IMO, especially for fuel lines!! Aaron Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted April 2, 2007 Author Share Posted April 2, 2007 Aaron, The hard fuel lines are 5/16" so I am going to try using 5/16 tube compression fittings to -6 AN adapters. It would be tough to flare the tubes on the regulator so I am going to try the compression fittings. I realize that they are not the best case scenario but it seems like the easiest bolt-on way to go right now. AN-6 <---5/6" compression tube Bo, I am moving the regulator over to the right front inner fender where the fuel lines come up from the tank. This is to clean up the bay by minimizing hose clutter. If the compression fittings leak, I will flare or solder and/or get a new regulator with NPT fittings. The compression fittings are all going to be in a pretty safe spot on the right inner fender, should a small leak develop. The fuel rail will be a dead end even in the way I am plumbing it. Quote Link to comment Share on other sites More sharing options...
aarang Posted April 2, 2007 Share Posted April 2, 2007 Ya , I guess with the stock regulator, you are kind of limited with the flaring option. If you're going to go through the trouble and expense of using AN lines, it might be wise to get a different regulator. I run my Aeromotive 13301 dead-ended like you to the rail, and I don't need a "T" in between, as the regulator has four pressure ports and one return on the bottom. It is also adjustable. I think I paid about $125 through Summit a few years back for it. It looks cool ( important!!) and it works great. Well worth the money. Aaron Quote Link to comment Share on other sites More sharing options...
wrxand280z Posted September 13, 2007 Share Posted September 13, 2007 Sorry to bring up an old tread, but the way he plans on running the fuel regulator after the return line wouldn't that mean that all of the fuel would be routed back to the fuel tank vs going to the carb? I would think that you would need to run a bypass regulator with one line going to the carb and the other to the return line. If you can run the lines like he has it it would save about 70 bucks for a bypass regulator vs a two port regulator. Quote Link to comment Share on other sites More sharing options...
hughdogz Posted September 13, 2007 Share Posted September 13, 2007 Aaron,The hard fuel lines are 5/16" so I am going to try using 5/16 tube compression fittings to -6 AN adapters. It would be tough to flare the tubes on the regulator so I am going to try the compression fittings. I realize that they are not the best case scenario but it seems like the easiest bolt-on way to go right now. AN-6 <---5/6" compression tube Ahh...that's how you do it! I couldn't find those compression fitting types of AN fittings. Thanks for the link Cygnus!! I went the "home desperate" route (term courtesy of BRAAP ) I bought a brass 5/16" compression to 1/4" NPT fitting. Then I had to get a 1/4 NPT coupler to covert it to female, so I could then use a 1/4" NPT to -6AN. I would think that the one piece is better than three (and definately look better). When I put the compression sleeve on the fuel line, I had to use 1200 grit to remove the plating and smooth it out to get the fit right. Then, to get it really tight, I was glad the fitting was Brass so I could really torque the sucker on there. I'm sure the AN one won't leak or else they couldn't keep selling them for FI. Regards, -Hugh Quote Link to comment Share on other sites More sharing options...
Pop N Wood Posted September 13, 2007 Share Posted September 13, 2007 Go to the summit racing or JEGS web site. They sell every manner of AN to tube to hose connector imaginable. And it is all indexed very well, especially on the summit site. Home Depot stuff is not AN, it is JIC. The flaring angle is the same but from reading countless posts there can be subtle differences in the threads. The only real problem with the JEGS aluminum AN stuff is costs can add up really quick. That was one of the bigger suprises in my build, the final cost of all the fuel line stuff. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 13, 2007 Author Share Posted September 13, 2007 Thanks for bringing up the thread. It's been working fine for months so the semi-dead-head setup of the fuel rail works. The ONLY drawback is that it takes about a minute for the AFR's to get back to normal after a hot soak start. All of the hot fuel has to leave through the injectors instead of a return line. It's not a huge deal and it looks cleaner. Besides, I usually pop the hood when I park it hot anyhow. The fuel filter is on the stock supply hard line. The regulator is on the stock return hard line. Quote Link to comment Share on other sites More sharing options...
Nigel Posted September 13, 2007 Share Posted September 13, 2007 I'm not sure you'd have the same issue with a dead-head setup, but I found that placing the regulator far away from the fuel rail caused significant fuel pressure problems. Here's the link to the post I wrote when I discovered this issue... http://forums.hybridz.org/showthread.php?t=105772 One other note... From my recent observations, I suspect that it's not hot fuel that's causing your AFR's to go out of wack on hot restarts, but rather the air temp. I have my IAT sensor in much the same place you do, and the air temps rise considerably when the car is shut off (as much as 60deg F). This leans out the AFR a lot on my SDS system, and I would imagine it does much the same for MS. Nigel '73 240ZT Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 13, 2007 Author Share Posted September 13, 2007 I'm not sure you'd have the same issue with a dead-head setup, but I found that placing the regulator far away from the fuel rail caused significant fuel pressure problems. Here's the link to the post I wrote when I discovered this issue... http://forums.hybridz.org/showthread.php?t=105772 One other note... From my recent observations, I suspect that it's not hot fuel that's causing your AFR's to go out of wack on hot restarts, but rather the air temp. I have my IAT sensor in much the same place you do, and the air temps rise considerably when the car is shut off (as much as 60deg F). This leans out the AFR a lot on my SDS system, and I would imagine it does much the same for MS. Nigel '73 240ZT I can change the effect of the IAT by reducing it's effect to zero and see if it makes a difference on hot starts. As far as the regulator location and the length of the vacuum/boost reference; my MSII ECU uses a vacuum hose that is about four feet long to determine MAP and it responds INSTANTLY to throttle changes on the datalogs. Unless the fuel regulator requires a so much more of air volume to move the internal diaphram, and it might, it should react as quickly with only about 3 feet of hose. Experimentation might be worth it because my AFR's do move around a bit during quick MAP changes. Although I was able to mostly "unspike" the lean with AE (acceleration enrichments). Interesting thread you had anyhow. Quote Link to comment Share on other sites More sharing options...
hughdogz Posted September 14, 2007 Share Posted September 14, 2007 Kind of off topic, but WOW you did a superb job on the wrinkle paint for the IC tubes!!! What's your secret? Also, Pop 'N Wood...serious thanks for the heads-up on AN versus JIC. Looks like I'm going to do the purely AN route sooner than I thought. I thought the coupler (in the air compressor section) was 1/4" NPT, not JIC. Hmm...no wonder I only got about four threads of engagement. Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 14, 2007 Author Share Posted September 14, 2007 Wrinkle paint in a spray can from Eastwood after cleaning with a pre-paint cleaner. Make sure everything is over 75 degrees F. Spray one coat pretty heavy. Wait 3 minutes. Spray a second coat heavy. Place in the hot sun and rotate every few minutes or bake in an oven at 150 deg F for about an hour. I used a small oven for the small stuff and the kitchen oven for the pipes. Open your windows though! Quote Link to comment Share on other sites More sharing options...
wrxand280z Posted September 14, 2007 Share Posted September 14, 2007 Man thats a great looking engine bay Sorry I understand why it would work on your cars. You are running fuel injection where I'm running a carb for a SBC. I would think that the extra fuel pressure would flood the carb. Or do you think that it would work on a carburated engine? I don't know much about fuel systems but if the regulator is restricting the pressure to 6.5psi to the return line all of the pressure before the return line would be the same pressure as it would be coming from the pump thus flooding the carb. Am I correct in saying this? Quote Link to comment Share on other sites More sharing options...
phil280zxt Posted September 14, 2007 Share Posted September 14, 2007 The black wrinkle paint on Dave's car looks 100 times better in person!! Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted September 14, 2007 Author Share Posted September 14, 2007 wrxand280z....that's exactly what I have too. Raising fuel pressure to a carb would be a bad idea. You might flood or spill the fuel out of the carb and fire, fire, fire. Thanks for the compliment Phil Quote Link to comment Share on other sites More sharing options...
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