yamahondarider Posted December 3, 2013 Share Posted December 3, 2013 Hey guys, I'm looking to get more power out of my L28 in my 76 280Z, its currently N/A. I've considered doing a chevy swap and as much as I want to, the motor is clean and appears to have been rebuilt in the past and everything just works flawlessly right now so I can't see yanking it. I may get some flack for this but rather than a L280ET swap out of a ZX I've considered another possiblity, an ebay T3/T4 manifold, an Ebay T3/T4 hybrid turbo, and plumb it into the stock throttle body either held wide open or butterfly removed. I'd then put a Holley 4 barrel in a draw-thru configuration and of course, use the throttle and all on that, essentially making the stock throttle body part of the piping. Another choice would be to replace the throttle body with a piece of tubing. Now this is all fine and dandy, but my other concern is ignition. Is there any way I could mount the TPS to a carburetor? And if I do so, could I just unplug the fuel injection harness and remove the AFM and let the computer control the stock ignition? If not, can I wire in an MSD box with boost retard to the stock distributer pickup to control ignition? That may be easier, however more expensive. Just wanting to bounce some ideas off you guys as I'm sure you know more about forced induction than me. I understand the parts I want to work with are not of the best quality however I'm willing to take that risk. If nothing else, it'd be a fun learning experience! Quote Link to comment Share on other sites More sharing options...
seattlejester Posted December 3, 2013 Share Posted December 3, 2013 (edited) I am almost positive that all the 240-280z's run a distributor run ignition signal, kind of foggy right now, mid day drowsiness, but pretty sure that they all have a distributor to run the ignition. I am kind of confused as to why you would need a TPS signal in a draw through setup. The stock system uses an AFM instead of a TPS, and adding a TPS in a draw through carb setup seems strange. Essentially you won't have any computer controlling anything, you would be getting boost while staying all analog. Having some kind of boost ignition retard would be preferable. I believe MSD does make a boost ignition retard box that can retard the distributor signal. Which motor do you have? What are the specifics? If the plan is to get all ebay stuff, you really can't blame anything for failing, in fact unless you have experience with specific turbo's or manifolds you may be setting yourself up for failure. I've seen ebay turbo's work very rarely, a used quality turbo or even a rebuilt junkyard turbo isn't much more expensive, I would definitely lean towards that. You could probably find a 280zx turbo manifold for cheap as well, and it would be guaranteed to bolt up, not 100% sure if you have round ports, but if you have square ports definitely. If you are on a budget, there are quite a few ways to make the car a little faster and much more enjoyable and those options may be more appropriate, as starting a draw thru project can eat up a lot of time and can put the car out of commission until everything is sorted. With that said, it has been done, usually with an aftermarket manifold, the plumbing would get complicated if you tried to use the stock EFI manifold. The compressor outlet has to be routed to the inlet on the EFI manifold, and on top of that you have to mount the carb in front of the turbo, and feed that into the inlet of the turbo, space becomes quite the challenge. http://i8.photobucket.com/albums/a48/cjh1452000/Carburetor2.jpg The most frugal setup I've seen is someone used the stock exhaust manifold, and ran a pipe all the way to the front, mounted a small turbo, a bored out SU carb, and then routed it to the stock carb manifolds via a split tube. It is a neat little project, it does require quite the intricate knowledge of all the parts that go into building a turbo system, more so since you won't get the precision you get with electronic control. You have to know what each system does, and then figure out a way to do it without using the easy method. Fuel for instance, in a normal boosted car, you would use a rising rate or boost referenced fuel pressure regulator to up the pressure as you up the boost and increase the injector duty cycle, in a draw thru setup more vacuum is applied to the carb and more fuel is drawn thru the turbo. Since you can't just increase pressure to a carb to get additional fuel there since carbs don't like high fuel pressures, you have to increase the fuel line size and source a high volume low pressure pump. An alternative method to meet each circumstance has to be solved, if you are up for the challenge and have the knowledge base to pursue it, it is a pretty fun task. Some things to consider are that off boost, the path the fuel has to travel before making it to the intake is quite long, pooling fuel in the compressor housing, heat soak, and so on. Good luck! Edited December 3, 2013 by seattlejester Quote Link to comment Share on other sites More sharing options...
yamahondarider Posted December 4, 2013 Author Share Posted December 4, 2013 Okay, things are starting to make sense now. I wasn't sure if a stock manifold could bolt up a T3/T4. I was under the impression that 76 L28 N/A motors had both AFM and TPS, and figured if using the stock computer for ignition only I'd need some sort of reference to the throttle position or engine RPM to have the computer control ignition timing. It does infact have a distributor. This may be more of a pain in the arse than its worth, but I have yet to find a single turbo ZX or complete engine setup around me that doesn't cost an arm and a leg. I believe the motor has a cam in it already, it has a lump idle similar to that of a cammed V8 and the power really comes alive over 3000 RPMs and pulls to 6000 (the highest I've revved it to). The valve cover has definitely been off as its been repainted (very well actually) and the intake had also been painted, so I'm pretty sure someones had this motor apart before. Lots of new stuff under the hood. I know its an older restoration, that has since spend some time outdoors..... I may sell it and buy a roller or worse-off cheaper car to dump a small block into. Turbo isn't out of the question yet, but I've got a lot to think about. Quote Link to comment Share on other sites More sharing options...
redzedturbo Posted December 4, 2013 Share Posted December 4, 2013 go Ls based truck engine 4.8 or 5.3 they are going for 300-500 bucks and are built well or just go get all 280zx turbo parts run it on what you have with like 10-12 psi. I highly recommend megasquirt if you go the l28et route. Im working on finishing my 3rd car using it and it gets easier every time. Best of luck. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted December 4, 2013 Share Posted December 4, 2013 Stock parts are available to turbo your car. If you're in a tight budget then fabricating a lot of parts would be more expensive. I also recommend a megasquirt. Quote Link to comment Share on other sites More sharing options...
yamahondarider Posted December 4, 2013 Author Share Posted December 4, 2013 megasquirt interests me. How hard is it to program? I haven't dug too far into it but it seems like a good way to control fuel injection and would work well for a turbo 5.3 LM7 build (for one of my other cars). I've read a lot into the LSX motors, especially the 5.3 LM7. the flow characteristics of that motor right out of the box is insane. With just a carb intake, 750 carb, MSD controlling the ignition, a cam and valve springs they made 433 horsepower at 6,800 RPMs. Insane little motor. They are cheap too, however cams are pretty damn expensive ($350) and thats over twice what a SBC cam goes for. Granted, much more bang for your buck. Quote Link to comment Share on other sites More sharing options...
Xnke Posted December 5, 2013 Share Posted December 5, 2013 I had my car driving well enough to make a three hour trip in four hours. Megasquirt is not difficult, but you must read the manual a few times to make sure you understand it. There is a lot of info in the EMS forum here, too. Quote Link to comment Share on other sites More sharing options...
yamahondarider Posted December 6, 2013 Author Share Posted December 6, 2013 I had my car driving well enough to make a three hour trip in four hours. Megasquirt is not difficult, but you must read the manual a few times to make sure you understand it. There is a lot of info in the EMS forum here, too. Yeah I actually have been spending some time looking into it, looks like Megasquirt one is easy, and correct me if I'm wrong but aren't 280z injectors batch fire? aka, they all spray at once? I wouldn't take much to rig that one up and it looks like an average MSD with a boost reference would be plenty for spark control. Then I could basically run whatever turbo I want and use the stock EFI system, of course with bigger injectors (would ZX turbo injectors be suffiecient for a T3/T4 making around 15 lbs?). if I could get 300 WHP would of the 280 I would be incredibly happy. the fender tag says 175 and I'm sure its lost some since then so I could see this working out rather well. Quote Link to comment Share on other sites More sharing options...
Xnke Posted December 6, 2013 Share Posted December 6, 2013 (edited) The stock turbo EFI system will work just as well as anything else up to about 12lbs, or 10lbs intercooled. After that, it's time to bid the stock EFI farewell, as it will be more trouble to keep running properly than it would cost to completely replace it. The stock non-turbo system is not something I would recommend at all. Stock L28e fuel injectors are not up to the job, they are 188cc/min, and are good for about 180HP. Stock turbo injectors are 265cc/minute, and can take you to around 220-230HP. The stock EFI is less than adequate for your goals. If you add an intercooler to the stock L28ET engine system, you will be on the limits at 10-12PSI and about 210-220HP. If you are planning to run a bigger turbo, you will need a standalone (can't think of a single piggyback that will work with the stock EFI) or an EFI swap from a different car, you will need bigger injectors, and you will need to spend the time and money to tune your engine with the engine management you choose. There are bone stock engines with the proper bolt-ons, engine management, and tuning making 450+HP out there. Edited December 6, 2013 by Xnke Quote Link to comment Share on other sites More sharing options...
yamahondarider Posted December 7, 2013 Author Share Posted December 7, 2013 The stock turbo EFI system will work just as well as anything else up to about 12lbs, or 10lbs intercooled. After that, it's time to bid the stock EFI farewell, as it will be more trouble to keep running properly than it would cost to completely replace it. The stock non-turbo system is not something I would recommend at all. Stock L28e fuel injectors are not up to the job, they are 188cc/min, and are good for about 180HP. Stock turbo injectors are 265cc/minute, and can take you to around 220-230HP. The stock EFI is less than adequate for your goals. If you add an intercooler to the stock L28ET engine system, you will be on the limits at 10-12PSI and about 210-220HP. If you are planning to run a bigger turbo, you will need a standalone (can't think of a single piggyback that will work with the stock EFI) or an EFI swap from a different car, you will need bigger injectors, and you will need to spend the time and money to tune your engine with the engine management you choose. There are bone stock engines with the proper bolt-ons, engine management, and tuning making 450+HP out there. Sorry, I was a little unclear. By stock EFI system, I mean't stock intake and throttle body and injector clips with bigger injectors, tuned and controlled by Megasquirt with an MSD ignition with boost retard built in running the ignition system, none of the stock computer or harness (other than plugs) would be used. What kind of injectors could I replace the stockers with to support upwards of 250HP without breaking the bank? I heard that the injectors are the same or similar to GM injectors of the new age motors but I can't confirm that. Ideally, I'd like to be running a T3/T4 and if it bolts onto a stock turbo manifold I'll buy one, I'd then like to pipe it to an intercooler and back to the intake. I'd like to do 15-18 lbs of boost reliably. I don't need to make necksnapping horsepower but I'd like to be able to spin the tires in 1st and second gear and be pretty damn quick. Shouldn't be hard considering how light the car is. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted December 7, 2013 Share Posted December 7, 2013 Try motorman for fuel injectors. You'll need the ford cfi injectors that came on 80-85 5.0 engines. I think I paid $30 each. They are 440cc. Quote Link to comment Share on other sites More sharing options...
yamahondarider Posted December 7, 2013 Author Share Posted December 7, 2013 Try motorman for fuel injectors. You'll need the ford cfi injectors that came on 80-85 5.0 engines. I think I paid $30 each. They are 440cc. Are they a straight bolt in? stock fuel rail? What did you do for pump and regulator? I know on Turbo LSX's MS1 runs via throttle position sensor, inlet air temp sensor, and coolant temp sensor, map sensor (built in) and a wideband for good tuning. Is it the same for a Z, or what did you use? Quote Link to comment Share on other sites More sharing options...
Xnke Posted December 9, 2013 Share Posted December 9, 2013 You can configure your Megasquirt in such a way that you can run MAF, MAP, or Alpha-N, on any engine out there. You don't need the MSD ignition box with MS-Extra, it can do your ignition timing too. Quote Link to comment Share on other sites More sharing options...
skirkland1980 Posted December 10, 2013 Share Posted December 10, 2013 They are nearly a direct replacement. Rather than the hose being permanently attached to the injector, you will use two clamps per injector. On the 83 na I'm running stock rail, pump and regulator. The 83 turbo I'm using the same injectors but with custom rail, wally 255, and aeromotive regulator. Quote Link to comment Share on other sites More sharing options...
gorillaman2012 Posted February 27, 2014 Share Posted February 27, 2014 Any chance this draw through setup is still going on? Have one of my own I'm going to be using also. Quote Link to comment Share on other sites More sharing options...
Tony D Posted February 27, 2014 Share Posted February 27, 2014 Isn't all this in the Megasquirt Forum Section Archives and FAQ? Holley Draw through fueled by the EFI pump with reducing return regulator to an eBay acquired SU manifold with a tube connecting the two, and maybe methanol or water injection... Stock distributor with MSD BTM ... Easy Peasy Lemon Squeasy... Around 250-275.... Quote Link to comment Share on other sites More sharing options...
SuperSamuri Posted March 22, 2014 Share Posted March 22, 2014 Just purchased a '71 240Z with a Holley blowthrough (or is this a drawthrough?) set up with a Garrett AR 50 turbo and a large intercooler and adjustable boost set at 10lbs. New member, and any additional info on this set up or any members personal experience would be appreciated. Initial idea was to do fuel injection (probably Megasquirt) but the car drove really well on a 100 mile freeway run from the Bay Area to Sacramento, Still have to drive in back to Los Angeles at the end of the month. few things to take care of first including bleeding the brakes. Car was a non op since 2010. Quote Link to comment Share on other sites More sharing options...
Tony D Posted March 22, 2014 Share Posted March 22, 2014 That's an Intercooled blow-through setup. Quote Link to comment Share on other sites More sharing options...
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