Guest SeanyD300zxT Posted February 23, 2003 Share Posted February 23, 2003 trying to figure out how to mount two aux. injectors in to the stock TB pipe. ust trying to figure out what kind of bosses I should mount on the pipe, and how I should seal them. what kind of mounting and what not. should they try and spray parallel to the airflow...or can they spray just perpendicular into the air flow. The current plan is to run 2 injectors of a seperate fuel system, with a seperate pump, lines, regulator and EIC computer as well as a small aluminum fuel tank I've got in the garage....about 10 L...an fill it with something other than regular gas...just an alternative to an intercooler and adding the needed fuel for boost! an when it comes time..water injection to clean things out anywho..any thoughts on how to mount them ? Quote Link to comment Share on other sites More sharing options...
Guest De Schmaydee Posted March 5, 2003 Share Posted March 5, 2003 .....i have been planning a 12 injector deal for a couple of years.....read a little about it....the fuel thats shot in before the throttle body will only help in a low boost application.... .......what i did was have a 12 injector manifold made w/the bungs for the second set about 2" up the runner on the intake from each stock injector...then had 2 fuel rails made....one for the original 6 injs and one for the second 6 that were to be controlled by an hks aic....you can see a pict of one like it in maximum boost....... .....this will give you the correct fuel delivery for really high power....i wouldnt be put off by an intercooler....its one of the best ways to help increase your boost...... .......i just (yesterday) decided to go w/the JWT ecu upgrade.....the 12 inj was just gonna be too much (for a daily driver).......s Quote Link to comment Share on other sites More sharing options...
Clifton Posted March 7, 2003 Share Posted March 7, 2003 SDS and HKS both make inj. holders. You can get steel or aluminum I got some from AZZcar. I welded them into the tubr just before the TB I run add inj on my Z and truck, both turboed. On my cay they sprayed into the airstream, on my truck they spray torwards the TB. I can send a pic of each if you'ld like ideas. IMO It sounds like you are trying to make your setup complicated. I prefer running it all on the same fuel system. There is nothing to worry about or remember to fill. If you need an intercooler I would put one on instead of water injection, again put it on and forget about it. Quote Link to comment Share on other sites More sharing options...
Guest SeanyD300zxT Posted March 7, 2003 Share Posted March 7, 2003 the goal isn't really to make something complicated...just something I was thinking about trying. as for running 2 different fuel systems....partly for the 'hey thats cool' factor, but also just to try something diffent ( maybe run methanol in it..then dial down the main injectors so the thing passes emissions) but you're right...running it all off one has its simplicities.....have you had any problems with the extra injectors being mounted in your pipe? what level of boost are you trying. as for an intercooler, thats an eventual goal yes..but more when I get a good deal on a decent core. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted March 7, 2003 Share Posted March 7, 2003 Personally, I think you are going about this the wrong way. You did not state your HP or performance goal or what size injs you are dealing with, but bear with me for a while. Lets assume we are dealing with stock injs that flow 260cc. I use a formula that determines the amount of HP a set of injs can support at a conservative 80% DC. HP at 80% DC = (inj cc / 7) * # of cyls So 6 stock injs can support 222hp. Assuming the 2 extra injs will flow 100% (and they wont) then 8 injs can support 297hp. Now 6 SVO injs, rated a 378cc (36lbs) with the same formula can support 324hp, so why introduce the complexity of extra injs that cannot be properly controlled w/o an expensive EIC and still you are not gauranteed the proper flow pattern and fuel distribution. Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 7, 2003 Share Posted March 7, 2003 I'd rather upgrade the whole lot of the injectors! I believe that is part of what Scotty was getting at also. Quote Link to comment Share on other sites More sharing options...
Clifton Posted March 7, 2003 Share Posted March 7, 2003 I've had no problems. On my Z I've run up to 20 psi with 2 550's and have the dyno sheet in the Datsun L6 section. I'm only going with SDS because I need more fuel than I can get out of the current set up and I have a set of 550's ready to go in. On my truck (Toyota V6) I run 12 psi with 9:1 CR. One 550cc and one 260cc. It's been turboed for 11 months, daily driver and no problems. I do run a boost retard also. I'm happy with it on the truck as the AIC does not effect me passing emissions. I agree that it isn't as good as 1 larger injector with programable EFI or 2 injectors per cylinder with one being controlled with an AIC but I don't think that it is any worse than a carb. If you plan to run methanol, you'll need to double the cc's on the injectors compared to what you'd run with gas. Quote Link to comment Share on other sites More sharing options...
Guest De Schmaydee Posted March 7, 2003 Share Posted March 7, 2003 ......do some charcoal grill gas (propane) or nitrous.....i wanna hear about somebody doing the propane thang........ofcourse thats if you want to (and have the ability and desire to) mess w/it......(i just got the jwt thing and its a pretty good deal for me ((not for everybody)) i just need something to putt around in and need a little "extra" to pass on the interstate ((hehehe))).....if you dont need to run 11s- and youre not changing stuff all the time...especially if you get you can get a good deal on the maf and injectors....... ....and hp aint everything either.....the only hp that counts is what you can get to the ground and how good you are using it......saw a guy a few weeks ago in a 800-1000hp supra do a 14+ quarter......he oughtta be proud of that......(especially on tv).... ....and i dont know how all these guys doin' 300+ keep the drivetrain together in these cars......(the 280s w/the T5 or less).......and i dont know of anything else (tranny) that aint a bear to get in one.........s Quote Link to comment Share on other sites More sharing options...
Guest SeanyD300zxT Posted March 7, 2003 Share Posted March 7, 2003 Thanks for all the input....right now I do have a fuel computer sitting waiting installation, but right now just have to decide on the injectors I suppose....my aim is to hit 300hp. at the wheels.....when I had the turbo built, we sized it so that at 16psi with the numbers he fed into his computer the motor *should* be putting out 300 at the crank..which is great for what I want...all that assuming proper intercooler and fuel ect. Thanks guys, I did have the feeling that doing the extra injector thing would be the *easy way out* and 6 big ones being the proper way..now just to find injectors and make a new rail....dumb nissan rail! thanks again Quote Link to comment Share on other sites More sharing options...
fl327 Posted March 8, 2003 Share Posted March 8, 2003 i still like the idea of being able to run a bone stock efi system and have two injectors come on when the times get tough, stock efi wont take a alarger injector without running funny, and sure its not import tuning to its best potential, but for 500.00 a kit with the injectors, and keeping a perfectly running efi system that now can run high boost with a little less efficiency-but only when its on, i can live with that. Quote Link to comment Share on other sites More sharing options...
Mudge Posted March 8, 2003 Share Posted March 8, 2003 Len, what part of the injection system sucks, that it wont run a larger injector? Fuel pump I'm sure is a good one, and the rail might have to go (I was figuring on trashing it anyway), but other than that? All I can really think of is being stank rich on the low end, if running a constant fuel pressure and injector setup greater than stock, without a rising rate pressure regulator (which I dont know how effective those are yet). Quote Link to comment Share on other sites More sharing options...
Guest SeanyD300zxT Posted March 8, 2003 Share Posted March 8, 2003 Theres no much wrong with either approach...one had the advantage of a seperate fuel system. the other needs a whole progammable system....either or....depends on the preference...I know for a fact that the pump needs to be upgraded to a TT pump..no biggie though. just need to size the injectors and program the curve as best possible so that you still have the versitily of not being rich down low and lean up high. Now..finding injectors....and making a rail.... Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted March 12, 2003 Share Posted March 12, 2003 My son and his starion friends are experimenting doing this--take a look at this web site http://www.xmission.com/~dempsey/perform/injector.htm Quote Link to comment Share on other sites More sharing options...
Clifton Posted March 12, 2003 Share Posted March 12, 2003 My son and his starion friends are experimenting doing this--take a look at this web site [url']http://www.xmission.com/~dempsey/perform/injector.htm[/url] Using a cold start valve as on theis web site is a bad idea. There is now way to control the pulse width for increasing RPM and boost. It's either off or on. If the A/F is good at 3500 @ 10 psi, it will be lean at 5500 rpm @ 10 psi. This is what not to do. AIC's can be picked up pretty cheap on Ebay. Quote Link to comment Share on other sites More sharing options...
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