Growing tired of random issues from my 280z - Should I tear down and start from scratch?

[Cloveland]

There are tons of random issues with my '78 280z. Every time I go out and work on the car I think to myself, why is it like this or this needs to be replaced. 

I am thinking about removing everything from the car and starting over from scratch. I would like to see if anyone else have done something similar and see what their process was or lessons learned that they ran into. 

In my rough plan I am thinking:

1. Remove Engine
2. Remove all interior (including wiring)
3. Clean entire car of old grime and debris
4. Replace subframe (with apex subframe) to support an LS1 and install supports for T56
5. Install new engine
6. Install Painless wiring harness
7. Interior things
8. ???
9. Happiness hopefully

 

Yes, yes, there are more things here that I haven't detailed out, i would like to hear your opinion on what I could do better to refresh the car.

Thanks for listening to my rant

[Miles]

It is an almost 50 year old car. Restoration is a given. I did a ground up restomod on my 240z 10 years ago and the car has been reliable and a joy to drive.  My wiring was still like new so I didn't have to mess with that.  If you decide to do a rebuild spend a lot of time planning and estimating costs.

[grannyknot]

If you're putting a swapped engine in you might as well start from scratch, you'll be glad when it's done that everything was set up properly in order.

[Ironhead]

One of the things in my experience that makes older cars unreliable is corrosion in the electrical system, primarily the connectors.  You can track down all sorts of elusive and intermittent electrical gremlins, only to find the corrosion was the issue.  It is never ending, because once corrosion has begun, cleaning it off only seems to provide a temporary fix and it returns.

 

I have found once you re-wire the car (assuming you do it "right") all the nagging glitches and issues disappear.

[Phantom]

On 9/11/2021 at 6:06 AM, Ironhead said:

One of the things in my experience that makes older cars unreliable is corrosion in the electrical system, primarily the connectors.  You can track down all sorts of elusive and intermittent electrical gremlins, only to find the corrosion was the issue.  It is never ending, because once corrosion has begun, cleaning it off only seems to provide a temporary fix and it returns.

 

I have found once you re-wire the car (assuming you do it "right") all the nagging glitches and issues disappear.

Amen to that! The L28 in my '77 280Z was pretty much reliable but then I got a 2-owner car that had been messed with by the PO's.  Two issues that kind of kicked my butt were the bullet connectors for the engine temperature sensor.  This is a common problem in the 280Z's.  They are aluminum and over time start to oxidize.  That cause a"cold" signal to be sent to the ECU and it starts running the engine richer and then richer.  Clean them and all is better.  The other thing was all the little connector hoses and band clamps on the fuel injection system.  Seems like I was always leaking somewhere

That said.  I drove that engine 100,000 mostly happy miles.  Then I pulled it and did the JCI LS1 conversion in 2002/3. No issues with those components in the past 18 years.  Interestingly, other than the engine management specific wiring, I still have all the original '77 280Z wiring in the car.  Whaat I have done is install HID headlights which use a relay rather than running through the main ignition switch which lightens the load on that area and then converted all my other exterior lights over to LED's (ZLEDslights.com) which reduced the load on al that wiring.  Car is running good and a continual joy to drive for almost 30 years now.

I just have one question:  If you tear the car completely apart do you have the skills, $$, and persistence to put it back together and not relegate it to being yet another unfinished project that languishes for years and then gets sold or scrapped?

If you can't answer that question you should sell the car now while it still has some value.

 

[clarkspeed]

I agree, mechanically, most of the parts last an exceptionally long time, even when abused. L6 engine with efi and all other. But it is a really old car now.  Electrical things deteriorate over time. Electro-mechanical wear is an issue and unless preserved in a low humidity environment, corrosion at every connection. 98% of the time it is something simple to fix by troubleshooting with FSM, but sometimes, it will be very difficult to diagnose.

[AydinZ71]

+1 @clarkspeed 

 

I feel it is a balance between several considerations:

 

1) Anxiety about reliability - In my case, my own anxiety is sometimes worse than the actual consequences of running old(er) components. 

2) Budget - obvious

3) Your time - It is important to value your time. Unless this is literally a hobby, you will get frustrated with performing re-work. 

4) Down-time tolerance - Daily driver vs. race car 

 

I am Bias. I always tend go deep down the rabbit hole in most cases. I like knowing what is "new", and therefore unlikely to be the source of a problem when one is encountered. At 50 years old, your electrical insulation will be failing. It is brittle, and prone to shorting. The copper wiring will have started corroding (brown/green build-up). Not really an easy fix here, so I would just strip the car and start from scratch if you enjoy the build process. 

 

It isn't what you want to hear, but electrical and electro-mechanical devices are going to be a game of wack-a-mole. Unlike mechanical systems which are pretty darn reliable on these cars, you will have periodic failures on:

 

1) Switches

2) fuses and fuse trey wiring

3) engine electronics (but these are maintenance items): Distributor points or electronic module, cap, rotor, wires

4) wiring to and from all lights, including the light receptacles themselves. 

5) gauges and instuments