83turbo280zx Posted August 5, 2008 Share Posted August 5, 2008 when people buy supra injectors for their L28, are they coming from the 1JZ or 7MGE motor? and if so, what is involved in fitting these injectors to work with the Z efi connectors, and also the intake manifold. and how much psi of boost can i run in them given that i've already upgraded to a walbro 255 fuel pump, intercooler will be installed saturday, and so will the greddy adjustable pop off valve? Quote Link to comment Share on other sites More sharing options...
wigenOut-S30 Posted August 5, 2008 Share Posted August 5, 2008 I have a set of the turbo mk3 supra injectors. They are from the 7mGTE motor. I have a pallnet O ring fuel rail. As far as the connectors. The 7M connectors are hard to find, I used I think used corolla clips. Just cut your stock clips off and solder the new ones in place. Mine are 440CCs and should support up to 380-400rwhp depending on supporting mods. I did use the non turbo 7mGE mark 3 supra injectors before I went megasquirt and they seemed to work fine. I ran 14 psi of boost fine with the stock turbo.. I just upped the fuel pressure a tad.. Quote Link to comment Share on other sites More sharing options...
Calgary280ZT Posted August 5, 2008 Share Posted August 5, 2008 I have the 440cc injectors and had trouble finding clips...found some small bullet connectors that fit the injectors...that and a little soldering and shrink wrap would work for a while. Luckily, I finally found some clips, just in time. Quote Link to comment Share on other sites More sharing options...
ktm Posted August 5, 2008 Share Posted August 5, 2008 I have around 30 7MGTE clips in a drawer in my garage. I had trouble finding them like everyone else, so whenever I saw a 7MGE in the junkyard, I snatched the clips. You can use the Corolla clips like Gabe said, but you need to grind off the two little tabs on the injectors. Quote Link to comment Share on other sites More sharing options...
Quin Posted August 5, 2008 Share Posted August 5, 2008 Your injectors have nothing to do with how many pounds of boost you can run. What you need to be concerned with is duty cycle. Stock 7MGTE injectors are 440CC and at stock Supra fuel pressure (40PSI) you'll reach the 80% safe limit before 350rwhp.... I'm running 55PSI base pressure on a RRFPR and I'm still right at 85% DC at 350rwhp. Quote Link to comment Share on other sites More sharing options...
ktm Posted August 5, 2008 Share Posted August 5, 2008 Your injectors have nothing to do with how many pounds of boost you can run. What you need to be concerned with is duty cycle. Stock 7MGTE injectors are 440CC and at stock Supra fuel pressure (40PSI) you'll reach the 80% safe limit before 350rwhp.... I'm running 55PSI base pressure on a RRFPR and I'm still right at 85% DC at 350rwhp. That is an incorrect statement. Your injectors have everything to do with how much booost you can run. More boost = more air = more fuel. Duty cycle is simply a calculation of how long the injector is open relative to one complete cycle (720 degrees) of engine revolution. The injector size determines how much fuel is supplied for a given injector pulse width. The "duty cycle" limitation of an injector is because of the injector size, which directly affects how much boost you can run. Quote Link to comment Share on other sites More sharing options...
83turbo280zx Posted August 5, 2008 Author Share Posted August 5, 2008 Your injectors have nothing to do with how many pounds of boost you can run. What you need to be concerned with is duty cycle. Stock 7MGTE injectors are 440CC and at stock Supra fuel pressure (40PSI) you'll reach the 80% safe limit before 350rwhp.... I'm running 55PSI base pressure on a RRFPR and I'm still right at 85% DC at 350rwhp. haha ok well in that case i'll get geo metro injectors and run 30 psi of boost Quote Link to comment Share on other sites More sharing options...
JSM Posted August 5, 2008 Share Posted August 5, 2008 Why not run these injectors? http://www.fuelinjector.citymaker.com/catalog/item/4511825/4545870.htm#image_1 You can get them pretty cheap, can use the stock Fuel Rail if you wish or a custom one and injector clips are easy and cheap to find. Quote Link to comment Share on other sites More sharing options...
big-phil Posted August 5, 2008 Share Posted August 5, 2008 I have around 30 7MGTE clips in a drawer in my garage. I had trouble finding them like everyone else, so whenever I saw a 7MGE in the junkyard, I snatched the clips. You can use the Corolla clips like Gabe said, but you need to grind off the two little tabs on the injectors. I think the N/A clips are not the same as the turbo clips. I did the same thing only to find they don't work. Quote Link to comment Share on other sites More sharing options...
ktm Posted August 6, 2008 Share Posted August 6, 2008 Phil, I am fairly certain that most of the I obtained clips are from 7MGEs and not the turbo models and they fit my injectors. Maybe I got lucky. My injectors were flow tested at 503 cc/min as well so they were not the N/A injectors. I know that the Camry and Corolla clips will not work as the tabs are offset incorrectly. Quote Link to comment Share on other sites More sharing options...
Clifton Posted August 6, 2008 Share Posted August 6, 2008 Blue top DSM injectors are the same size and you don't need to swap connectors. IMO 440's are still too small unless you are keeping the stock turbo and low boost. I'm with Quin. 20 psi on a stock turbo 20 psi isn't the same as a GT40 or similar sized turbo. For what it's worth. The factory 7mgte ecu ran mine to 96% duty cycle at the rev limiter. That was with an FCD and going past what the stock fuel cut would have been at (12psi). Many people with 7M's have no problem getting 400rwhp with 440's. Quote Link to comment Share on other sites More sharing options...
Quin Posted August 6, 2008 Share Posted August 6, 2008 That is an incorrect statement. Your injectors have everything to do with how much boost you can run. More boost = more air = more fuel. Duty cycle is simply a calculation of how long the injector is open relative to one complete cycle (720 degrees) of engine revolution. The injector size determines how much fuel is supplied for a given injector pulse width. The "duty cycle" limitation of an injector is because of the injector size, which directly affects how much boost you can run. Yes and no. The OP made it seem like he thought that XXX size injector would instantly allow him to run XX pounds of boost, and that simply isn't the case. That's what I meant when I said injectors have nothing to do with how much boost you can run Clifton, that's pushing the injectors much too far in my opinion, just asking for a blown motor. Quote Link to comment Share on other sites More sharing options...
Clifton Posted August 6, 2008 Share Posted August 6, 2008 Clifton, that's pushing the injectors much too far in my opinion, just asking for a blown motor. AFR's were always good and it was just at the rev limiter, lower revs, lower DC. Did it for a few years and ALOT of others do it too, they just don't know it as they never check the duty cycle. On a 7M running more than 12 psi it's the same as mine was. If it was that bad I don't think a factory ecu would let it happen. I ran my 550's at 114% with MSII until I went with 700's. I think alot of the "don't go past 80%" is extreme precaution. If it was as bad as most people claim. I would have had an injector related engine failure long ago witht he boost I run. Quote Link to comment Share on other sites More sharing options...
Quin Posted August 6, 2008 Share Posted August 6, 2008 Little pot calling the pedal black here, as I'm running my 440s at 85% or so. AFRs are fine here, too, but I'm dumping fuel in with an AFC (old school five knob no display model FTW) and my base FP is around 55PSI. 15PSI, BPU on a 60 trim CT. Quote Link to comment Share on other sites More sharing options...
ktm Posted August 7, 2008 Share Posted August 7, 2008 My 440s were flow tested at 503 cc/min and I am at 53 psi base pressure. My DC's are around 85% to 90% at 20 psi and 5500+ rpm. Quote Link to comment Share on other sites More sharing options...
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