garyhooper Posted September 4, 2005 Share Posted September 4, 2005 I have a 76 280z FI mostly stock motor ( only exhaust is different). I have had so many troubles with the FI that I'm done with it. So I'd like to convert to SUs or maybe 4bbl. I know that I'll need new fuel pump, intake and carbs but do I need a new distributor as well? Is which conversion is cheaper? The car I'm going to sell when I'm done (body work is done but the engine needs work obviously) b/c I just have too many projects. What is the cost for a 4 bbl intake from someone like arizona zcar? While we're on the topic does anyone have anything like what I'm taking about for sale? I'd prefer something that doesn't need rebuild. Thanks for the input guys! Quote Link to comment Share on other sites More sharing options...
datsunlover Posted September 4, 2005 Share Posted September 4, 2005 If you search a bit, you'll find lots of info.. and a few posts by me for sure. I did exactly what you're thinkng, just in a 280Z. My stock FI was junk, and I started pricing out fixing it.. well.. I don't have over a $1000 to spend here, so a set of SU's w/ manifold and a 280zx distributor for $150 was the way I went. Oh, and I bought a generic 'carburation fuel pump' (3-5 psi)for $60 to replace the stock FI pump.Now, I have since rebuilt my motor and it has a HUGE cam in it (compared to stock) therefore doesn't run so great with the SU's anymore.. They just cant give it enough air...but last year (before the motor upgrade) it was great. Took about a week of fooling around, tuning, learning the carbs, and it was great. I'm considering going back to a FI setup, but not the stock one, only for the sake of fuel milage.. My carbs may be for sale soon... Quote Link to comment Share on other sites More sharing options...
garyhooper Posted September 5, 2005 Author Share Posted September 5, 2005 I'm curious why you switched the distributors. Is the original distributor not compatable with the SUs setup? Or was your's just going bad? How much of a difference is the fuel mileage? I think the last time I drove it I was getting around 18 or so with FI Quote Link to comment Share on other sites More sharing options...
Here comes trouble Posted September 6, 2005 Share Posted September 6, 2005 The old silver 78 Z set for a couple more years while I was away with no one paying heed to my instructions to start it. I soon discovered that something was wrong upon re-starting and I know nothing about EFI which I denied like an alcoholic. I entertained carburator replacement but decided to get an EFI educaction when the gas prices doubled. I still know little about EFI but I am learning. The gas tank was clean. I have a fuel pressure guage to monitor the fuel supply and a 240 SX throttle body upgrade and JSK fuel rail. Enough spare parts in the backyard to do some serious "parts changing". A recent thread indicated just re-connecting the ECU plug in can do wonders and my injector terminals are really cruddy. I figured the best way to start my EFI education was to make the parts pretty so I would enjoy furthering my education.. http://pg.photos.yahoo.com/ph/larryjohnson97438/detail?.dir=8223&.dnm=879b.jpg&.src=ph "When the going gets tough....the tough get going".....from former consumate bully Attorney General John Mitchell (married to cigar smoking Martha Mitchell) serving under the Nixon regime who later resigned his post and fled. Quote Link to comment Share on other sites More sharing options...
Guest Battle Pope Posted September 6, 2005 Share Posted September 6, 2005 I was in a similar predicament. 1976 280Z with an L28E from an '82 ZX. Butchered wiring. Car would fire on starting fluid, but without the starting juice it would flood out and not start. Couldn't figure out why it didn't work, and didn't feel like backtracking over a wiring mess, so I picked up a pair of webers on a manifold with linkage for a hundred bucks, got a 240Z balance tube with no emissions crap for 40, had the carbs rebuilt for 160, and I'm picking up my new air cleaners today. In total, I should be in the whole business under 400 dollars and should have a decently running car. I can't speak for fuel mileage because it didn't run with the EFI on it but after some major tuning I'm crossing my fingers at 18 mpg. Quote Link to comment Share on other sites More sharing options...
PeterZ Posted September 6, 2005 Share Posted September 6, 2005 SU's are still good for big cams. You can bore them out for more air and larger butterflies. Early Z-car injection is a pretty simple system to diagnose and tune for mileage or performance. Sounds like the cold start injection system wasn't working properly on the car that needed starter juice. For Ol' Timer: I found most injection problems have been dirty connections, especially at the injector. You can listen for the injectors to electrically click (or not) with a stethoscope. The cheap-o kid's scopes work well enough. Also, some injectors gum up and won't open without some help. A test light will tell you much about such things too. Good luck all. Quote Link to comment Share on other sites More sharing options...
ww Posted September 7, 2005 Share Posted September 7, 2005 The most productive thing you can do is clean every electrical connection. On cars of this age, corrosion is bound to have built-up to some degree. Pull each injector plug, clean it with electrical contact cleaner from Radio Shack, re-connect it and run a thin bead of dielectric grease around the outside of the gap in the connector. This will prevent any moisture from creeping through in the future. Do this to every electrical connection all the way back to the ECU. Once you get good electrical connections and your resistance on them is correct, you'll be amazed at how much better your car will run. Remember, all of the sensors including the O2 sensors run off of voltage readings. If the voltage drops because of a bad or corroded connection it will change how the system manages the engine and fuel mixture. In my experience, this has been the primary contributor to poor performance and gas mileage in these cars. Quote Link to comment Share on other sites More sharing options...
AK-Z Posted September 7, 2005 Share Posted September 7, 2005 WOW. learn something new everyday. dielec grease to seal the connection. I used to use elec tape but is a pain when you have to unplug something so I just quit doing that. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 7, 2005 Share Posted September 7, 2005 Wow, suprised nobody said it yet: You have an EFI car, why not simply stick a Megasquirt on it? Doable for low cost (probably under $500 for a DIY kit), and will give your car superior drivability and power over any of the other alternatives, including a functioning stock EFI system! Quote Link to comment Share on other sites More sharing options...
garyhooper Posted September 9, 2005 Author Share Posted September 9, 2005 I'm probably stupid but what's megasquirt? Quote Link to comment Share on other sites More sharing options...
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