I'd fix the stock system. That normally gives you the most reliable and easily serviceable system.

 

following. interested in the same.

 

Yes stay with the stock system. I dont understand how the dropping resistors can give you problems. Either they are good or bad. Do the FSM ohm check on them and replace them as needed.
Triples, doubles and 4 barrels are cool to look at but man..................getting them set up correctly can be a real pain and every expensive.

If you have it running that is 90% of the battle. Stay with it and get it running 100% correct and you wont regret it. Parts are pretty easy to find. DONT just start replacing parts just because they are 40-50 years old. If it aint broke, dont fix it! If you suspect something is not correct find the test procedure for that item and check it. These cars run the best with the EFI system as designed.

 

I’m a person all for newer efi, I think newer efi is super great even for stock NA cars.

One purchase of megasquirt kit with their new distributor, is most likely more reliable than the stock efi, better gas mileage, able to give you live data, etc etc the list continues of the benefits (if you want to go turbo eventually this is probably recommended).

But….you are saying this just because you have trouble with the stock efi and that you want to swap over to something else. First let me tell you something, I had my car for 2.5 years now I got when I was 17 now I’m 20, the stock efi even though I also have problems with it has been more reliable than my 2014 Honda odyssey and has less problems overall; this car will just start and go no matter how rich it is or how much you abuse it 😅. Carbs…probably the worst idea they look cool I assume but efi is just better in everything besides maybe a couple of milliseconds in throttle response. Honestly, 99% of the efi problems was because I was young and stupid and threw parts at it + band aid fix but the gas tank wasn’t my fault I swear! (I didn’t seal it properly)

The bottom line I’m trying to get to is all you are doing is putting a band aid on something that is most likely fine..you learn absolutely nothing by band aid fix after band aid fix. No offense (don’t want to go tony d mode) but if you can’t figure out a efi system that has like 8-10 sensors max I can’t imagine how much harder it would be for you to figure out how to setup a modern ecu and setting up the software + tuning just my 2c

 

Also very clean car I swear I saw this one somewhere while looking for zx parts!

 

I'd get the FSM and follow the diagnostics. It is phenomenal. It tells you all the areas to test, what order and most times even how to test the actual parts that may be bad before just buying new ones and hoping they will fix the issue. I resurrected a 1977 280z that had not driven since 2010 or earlier. With minimal money and patience and help from this forum I made it into a reliable daily driver. Look for some of the threads I started. There is a wealth of info in prior posts here on how to make these cars reliable with their original parts. Just my cents worth. Best of luck!

 

There's a series of excellent (IMO) instructional videos on Youtube about Z and ZX fuel injection. Most of the videos are relatively short and to the point. Here's episode one!

 

My buddies car had dropping resistor issues. Turned out it wasn’t the resistor. The issue was a wire separated from a pin on the connector. It tested bad at the connector and the wires looked intact. Curious, I opened the clam shell to see what the resistor looked like on the inside. Testing the resistance at the resistor rather than the connector confirmed the resistor was in fact good leading to a proper repair of the pin. Moral of the story: verify the component is actually bad. I wish you happiness with your Z. Oh, as to your actual fuel system question: get the system your trusted tuner is most familiar with. If you are the tuner, obviously the choice is which system you UNDERSTAND the best.

 

I agree with this in theory, with this reservation:

If you have a stock system, any competent mechanic can work on it because the parts, system and methodology of how to work on them are well documented.

If you have a modified system, the only people who know what's there and how it was installed are the installer and you. In that case, document everything and take copious notes.

 

While i haven't messed with stock EFI since 2006 or so. If your NA and just want it to run. Stay stock. Going aftermarket EFI can be very reliable. My current car for example. it can also be very problematic. Either you need money to pay someone to tune it or you have to know what your doing. And no offence but the fact that your asking which way to go from triples to standalone and don't know what to do. Makes me think your not that well versed in car mechanics. My current car is rock solid because I learned my lessons 15-20 years ago. I had massive issues with megasquirt back in the day. All where my fault. I didnt know what i didnt know. I could do so much searching and reading that i thought i knew it all. But some things you just dont know your doing wrong because you have never seen it done right.

Stay stock it will be the cheapest for now also.

 

Do a compression test on all cylinders and if they're all in spec don't touch that engine, as they can easily go over 200,000 miles. I had my 82' engine with 120,000 miles rebuilt and all the bearings were in spec and the cylinders still had OEM cross-hatching.

 

For the record: No one, including any top mechanic you care to consult or utilize can or will “throw on” a new stand alone EFI. Whether it’s an MSD, Megasquirt, FAST EFI or even a Four barrel carburetor it will take tuning, TIME and fabrication to work right.

 

In all my decades of working on z's I've had very little trouble with dropping resistors. I can count on one hand how many I've had to replace. Like someone mentioned earlier it could possible be the pin connectors for it. Matter of fact the biggest issue with the DR's that I've had is plugging the little buggers back in. I've seen a lot of people through the years change over to a different efi or a carb'd system because no one could figure out the stock efi. You can get a pin connector test out of the stock manual, or the EFI bible. That and a fuel pressure gauge that goes up to at least 65 psi are your best tools. Check all the connections on the injectors, and the 2 sensors on the t-stat housing, make sure the conns are clean and tight and replace the conns as needed. I stock 3 different types of the 2 wire connectors and even the 3 wire on the throttle valve switch. I also sell rebuilt air flow meters, rebuilt fuel injectors, rebuilt fuel pumps. The one thing I can't get rebuilt is the ECU also called the driving computer because no one can do them anymore. I did however just uncover 2 big boxes of used ECU's from a dark corner of one of my shipping containers so that's problems taken care of for awhile.
Z man of Washington