Project: Ghetto EFI!

[RacnJsn95]

After some thought, and reading stuff, I think I'm gonna try to rig up some ghetto efi! I've been trying to buy a older non-webbed, non-egr intake from an L28 off ebay, but they're too damned expensive... It figures when I sell one that's freshly blasted, and in super shape I only get 1/4 the price everyone else gets for there not so clean ones... I wish I woulda kept that intake now!

 

Anyway, I rifled through my crap, and I was lucky enough to still have an early intake (One that's straight, and doesn't have that gay bend in the plenum which you couldn't weld together if you cut the middle out), but it's webbed, and has an egr, so I'll have to work on it a little more than I would have if I had the ideal manifold, but that's ok... Here's the plan...

 

 

Looks good, eh? And in the pursuit of being even more ghetto I came up with another brilliant idea... I know people use the efi stuff off the 80-82 200sx, but it seems they're pretty much impossible to find, especially here... SO...

 

Has anyone ever though to use L28, or maybe L24e injection stuff? The early 280z injection didn't use an o2 sensor, so that simplifys things. The ecu fires off the - signal on the coil, and it's batch fire so all the injectors fire at once, so the firing order, or extra 2 inector plugs don't really matter.

 

Here's where it gets complicated... The ecu fires 1/2 the needed fuel every revolution for the L6, so every 3 ignition events (coil - signal) the injectors fire. Down side to this is since the L4 is a 4 cylinder, the injectors won't fire at the same point in the revolution each time, resulting in 2 cylinders in a row running lean, before the next to fire gets full fuel... But You could turn this around if you can get enough adjustment out of the AFM (there's a lot), to where 2 cylinders get full fuel (or close to it), and one will run rich... refer to the example below to see...

 

---HHFHHFHHFHHFHHFHHFHHFHHFHHFHHFHHF

134213421342134213421342134213421342

--X--X--X--X--X--X--X--X--X--X--X--X

 

H=Half full (or full if you're running one rich cyl instead of two lean). F=Full fuel(or one rich) X=Injector Fire

 

Bad idea, huh? It will probably run, but it might not run that great.

[mklotz70]

what does the ecu get it's signal from to tell it to fire the injectors? If it's a crank sensor with 3 places it tells it to fire....can you use a trigger with just two?

[521Lvr]

man I would hate to see you cut an n42 intake up like that.

good thing you sold it.:)

I tried what you are wanting to do.

by the time you remove the center and bolt the pieces to the head they will be 1/4" to 3/8" staged gap to weld up. meaning the back of the intake is closer to the head than the front.

so even after you ground everything rite they will still not be on the same plane. :mad:

you could spend alot of money and time haveing the gap welded up just to have it look like real ghetto sheeet.

my solution: cut off the intake runners as long as you can. bolt them to the head and put a straight edge on the part you cut and grind them straight.

Go to the metal supply and get a 4". thick wall aluminum round pipe 16" long or so. and a flat sheet of 1/4" or 3/8" thick, big enough to make a piece to cap off each end of the pipe.

Cut the holes in the pipe so the runners fit nice against it. cut your end plates to fit and have it all welded up. walla. ghetto intake.

1/4 or thicker on the ends will insure that you got enough material to drill and tap holes for mounting the TB. and vac hoses, etc.

does any of this make sense:blink: ramble ramble....

[SHADY280]

this is exactly down the road i was going. its good to see others trying the "true" ratsun intake. i was also going to try the l6 ecu, but if you figure, they are batch fired, 3 at a time, just use the front 2, and splice off those, then all 4 fire at once. and there are 2 choices of ecu, 79-81/1/2. and later ones. the early ones use a dropping resistor to the injectors, and the later does not. the later also uses a o2 sensor. im even gonna throw a turbo on there just to make it really exciting. then ill need all the fuel i can get. gonna try 5 psi first, then work from there.

[Bleach]

Where did you get the info on the L28 injectors firing like that?

I was thinking it was one batch; all six fire every revolution. The non-turbo 280ZX has no crank angle sensor. It just squirts a little each time and the mixture is close enough. Anything WOT or over 3K rpm is just open loop. (full fuel) those early ECUs really suck. The turbo version is hardly better.

 

What about the early Z20 200SX fuel injection? They use the same style AFM, throttle, and ECU. Just retrofit that system onto the 280ZX manifold you create. Or really any 80's Nissan. The older the better.

just some ideas

[datzenmike]

I plan to run the Z20 EFI on my Z24 so everything should bolt up.

 

The trigger for this system must be the IC distributor. The ECU muct calculate an injector pulse every second spark plug firing, or once per RPM. The ECU from a six cylinder will be confused by a four cylinder distributor won't it? What I'm saying is that the 280 ECU will fire every third plug firing in order to set an injector pulse every RPM on a six cylinder.

 

I believe the '82-'83 Z22s had the O2 sensor. The wiring for the Z20 and Z22 are very close. I wonder if connecting an O2 sensor from an newer one would work on an earlier one?

[tiltnose510]

I have a manifold you can buy cheap. I had triple SKs on my old L28 and the intake eventually got cut up. I can weld it back together and sell that to you for 25 bucks or something.

 

On my SDS EFI setup, it is a batch system and changing it from 6 cyl to 4 cyl required changing the eprom. outside of that, it used 3 wires to fire injectors and coil pack and all I had to do was disable one of them and use the remaining two wires. One wire fires two injectors. Can't you just get the harness, ECU and injectors from a KA24E and be done with it? I have harnesses forever more I will give you, ECU costs next to nothing, and injectors can be had for pennies.

[Jason]

Tiltnose, do you have an wiring harness for a KA24E available that's uncut?

 

Thanks

[RacnJsn95]

I guess I might be able to use the injectoion from a KA24, but how does it fire? The reason for using the old 280z system (or 200sx system), is that nothing special fires it, it fires right off the - side of the coil. Like datsunmike said the 200sx will fire every other ignition event (plug fire), and the 280z will fire every 3rd. The old L28 systems batch fire all 6 injectors at a time, they didn't start batches of 3 untill the 300zx intrucuded.

 

I'm pretty sure it would work, but like I said the fuel mixture wouldn't be that good. Like my little chart above, some cylinders would run on one squirt (half the fuel), and some would run on full (2 squirts)... but they alternate, so that's why I think it "might" run just ok, not great.

 

What's that manifold look like tiltnose?

[pl521sss]

Here's a picture of that manifold cut and welded.

It's someone's project that I saved.

 

 

[Fineline]

I dont think you can use a KA24 because (correct me if im wrong) it uses a cam angle sensor? That is one of the reasons people use the 200sx stuff. Here is a pic of my intake. I tried the cut and weld thing but as someone said it was more hassle than it was worth because you ended up 1/4" off. You can use the injector bosses from the 280 mani and fab from there.

 

[Icehouse]

I wrote this post this early but my phone didn't post it so I did a little updating to it :)

 

 

I wouldn't bother with the old L6 junk, at least skip up to the ka24e injection, like Mark said. It uses a MAF way better than the "flapper" shit about 10 years of advancements in computers is a lot. You could also get it re programmed too. I'm friends with a dude that ran it on his L20et he never got it dialed(SAFC2 isn't all its cracked up to be.) He said with minor mods the dizzy fits the L series. If it was an NA L20 with the ka managment it would run great I think.

 

If you are thinking of turboing the L I would run the SR ecu stuff. All 4 cylender nissans dizzy's share the same style "encoder wheel". Which means it may be possible, I haven't tried to mod the ka one with the sr one though, just a thought in my head at this point. This would make it much eaiser to get the SR coil packs working. If Doug would sell me an intake mani I could try it.. :)

 

I don't think the air fuel would be that far off. Think about what the ecu it looking for. Air volume, air temp, engine temp, throttle posistion. And rpm. Nothing about displacment. Plus in open loop the ecu tries its best to keep the fuel mixture optimal.

[tiltnose510]

The manifold I have is a canon and ws cut across the middle. It could be welded directly to a plenum or welded back together and used for sidedrafts again. Either way its been sitting in my shop for years now and isn't being used. I'd be just as happy to see someone do something withit but the cut l series mani does look cool.

 

I have several KA harnesses that are just missing the dash plug and some missing the main power plug which could just wired to for conversion stuff anyway. I'd give em up for 20 bucks each or something cheap.

 

The KA-E does use a dizzy but I think it has an encoder at the bottom. If it can be put in the L with minor mods, that would be the way to go. Other than that, a crank triger with hall effect sensor and magnets is pretty easy to setup. (I have an SDS hall sensor in the drawer too and Barry at SDSEFI.com sells magnets for under 20 bucks)

[Jason]

I'd be interested in a complete as possible KA24E harness, the fellow I got the engine from used his for a SR swap....

[RacnJsn95]

Tiltnose, Could you take a picture of the manifold and send it to me? If it's the manifold I think it is, and if I think I understand how you're saying it's cut, I would like to buy it from you. I could do a bolt on plenum, that would be cool, and a lot less work. I might also want a KA harness eventually, but I'll work on the manifold first.

 

There must be like one manifold that is straight, and not tilted. I went down to work today to use the band saw, to cut the manifold I had up. I went ahead and ground off/filled anything I knew I would not use at this point, here's how it turned out...

 

 

I ended up with the classic 1/4-3/8 off like everyone always does...

 

 

So I thought to myself, "Maybe I can just use a hammer to "massage" the plenum walls into place"... haha, it started out ok, but I soon broke off a 2x2" chunk out of the side, so I had to weld that back on lol! As of right now, it's still about 1.25" too wide, but I left quite a bit of material on the one side, as I had to cut it by hand in the band saw...

 

So I'll try to borrow a grinder from work and get these bolted onto an old head , and them try my next big idea... I'll bolt the sides to a head, and then use a (some?) clamps, and some flat bar to try and clamp them straight, then weld them.

[tiltnose510]

You can always work with the gap and just bend a plate over it too and weld the sides of the plate. I'll get pics of that manifold for you.

[sjeff64]

I hope this doesn't seem like a really stupid question,but,everyone seems to want to cut the manifold in sections getting rid of the center.if all most people want from the manifold are the injector bosses and the mounting flanges,since you have to weld up the aluminum anyway,why not just cut it front to back as close to the intake plenum as practical (and square to the head)and use box tube as the the plenum?

[sjeff64]

and I don't know of any l motor that has a factory crank angle sensor.All nissans are batch fire without heavy mods

[datzenmike]

One thing's for sure, you'll need the oil pump drive spindle to work the KA dizzy in an L series. The KA spindle, (far right) has splines to remove slop and make the crank angle sensor more accurate. The other spindles are from an L24E, Z24 and either a Z20 or an L20B for the last one. It's been a while and I can't remember the right order I put them in.

 

http://i138.photobucket.com/albums/q251/datzenmike/CopyofIMG_0376.jpg[/img]"]

 

 

So I'll try to borrow a grinder from work and get these bolted onto an old head , and them try my next big idea... I'll bolt the sides to a head, and then use a (some?) clamps, and some flat bar to try and clamp them straight, then weld them.

 

If you warm up steel you can put some bend in it. Will aluminum do this? Maybe put some up bend in the front runners and down bend in the back ones.

[RacnJsn95]

I hope this doesn't seem like a really stupid question,but,everyone seems to want to cut the manifold in sections getting rid of the center.if all most people want from the manifold are the injector bosses and the mounting flanges,since you have to weld up the aluminum anyway,why not just cut it front to back as close to the intake plenum as practical (and square to the head)and use box tube as the the plenum?

 

I personally just want to keep the factory plenum because I think it will look clean and kinda factory. If I cant get the plenum to line up, then I'll probably just cut the runners off about 1-2" past the end of the injectors, and build something similar to fineline's manifold.

 

You can always work with the gap and just bend a plate over it too and weld the sides of the plate. I'll get pics of that manifold for you.

 

Yeah, I thought about doing that, but I don't think it would look that clean, and I think it probably wouldn't flow as well.

 

As far as heating the aluminum to try and bend it, I'm not sure if it will work or not. Cast aluminum doesn't seem to be that flexible, but it's worth a try... I thought of just slicing the top half of one side of the runners, and then the bottom half on the other side then clamping them straight, and filling the slices after that... We'll see what happens...

 

It's really too bad they changed the deck height so many times... If I were to try and put a KA distributor on the L18, it would be a lot easier than an L20b... Because the L24/26/28 has the short deck height of the L16/18, right? I see your spindle picture there mike, it looks like that KA spindle, and the L24e one are the same length? The 82-83 L28et spindle looks to be the same as the KA24 spindle. If the KA one is the same length as the L one, it would work. The L28et spindle is splined on the end, like the KA, but it's too short for the L20b :(

[Icehouse]

My buddy said he just ground the dizzy to make it fit right. He said be very carefull you do it right. On the first try he said his wrong and it rubbed while it was running which made metal shavings thus destroying the bottom end. Find the correct rod may help. If I only had an L motor I could try this :) maybe if I get the other 68 2 door I can try it :)

[sjeff64]

well if it works well you can build the same for me

[RacnJsn95]

Find me an non-webbed, non-egr manifold to do it with, and I'd think about making you one jeff... The webbed ones are too much work.

 

Anyway, I think I solved the spindle problem. I thought I remembered that the end of the distributor was just held on with a roll pin, so I went and dug through my crap. Sure enough, it is... I suspect that a KA distributor will also be the same, the splined "sleeve" is probably held on by a shear pin. SO, it may be possible to take the non-splined one off a normal L motor, and put it on the KA dizzy so you can use a normal rod.

 

I dug out my L28et drive spindle, and what I believe is an L28e one. The lengths are the same, the only differences are the bigger part at the top is splined on the turbo one, but the OD looks to be the same as the non-splined one. The other diff is that the "half-circle" at the top is turned down smaller, but they two look to have the exact same cut, so I bet that if you taked the splined sleeve off the KA, and just put the L "stright-through" sleeve on it, that a normal L drive spindle will work with the KA dizzy... Worst cast scenario, the whole shaft on the KA dizzy is turned down to the size of the top of the spindle circle, I might have to make my own "straight through" sleeve, with a step down for the distributor shaft size... But I'm hoping that the shaft is the same except for the last part where it's turned down. So in theory, it might be pretty easy to just make the KA dizzy work with the stock L20b spindle :)

 

[521Lvr]

I believe the intake you need was only from a 75 280z. The only year for EFI and no EGR.

I know a guy here that owns "The Z Barn". He has a few of these if you got the $100+ to put out for 1. sales@zbarn.com

[tiltnose510]

I must say gents, this is what a forum should be. We'll come up with something together yet, compile it and put it in the tech section.