280z Fusible Link Upgrade

[wheee!]

I'd like to see a write-up of how to route the fuel injector wires so they go along the firewall, then to the back of the intake manifold. 

 

When I get to doing mine, I will try and accomodate if it has not been done already. I plan on splitting the harness for just this purpose. Plus I am going to 11mm barbless injectors so I need to redo the wiring regardless.

[Captain Obvious]

My thoughts? I honestly don't know. My questions are:

 

"Is there any functional difference in operation between fuses and fusible links?" and the follow-up question of

"When designing in a protection device, what would make you choose a fusible link over a fuse?"

 

I spent a little time looking into the above questions a while ago and about the only thing I could turn up on-line was that fusible links were historically used in applications where fuses were unavailable because of the current capacity.

 

So back in the mid seventies, forty and fifty amp fuses, especially in the glass tube style used in our fuse blocks simply weren't available. But if you look under the hood of cars now, you see cartridge fuses of 100A or even more coming right off the battery terminal. I guess the answer could be that parts like that just simply weren't available back when our cars were designed, and if they were designing them again today, everything would have been fuses instead of of fusible links.

 

However... In engineering, frequently even the seemingly mundane is often much more complicated than it appears to the non-expert. I wouldn't be surprised if an EE from Bussman would be rolling his eyes right now at my lack of understanding.

[S30Driver]

Over a year since installation, DB Link unit still going strong & have had no issues with it.

For clarity, it uses mini ANL fuses ...

[Patcon]

Thanks Bruce. Always nice to get a "Sparkys" input on such things.

[TomoHawk]

Can you get fuse locks with 1pair or 4 inline cartridges?  If you set it up right, you may be able to make it look like the factory fusible link setup.

[Captain Obvious]

Always nice to get a "Sparkys" input on such things.

 

Haha! My pleasure. Just remember that I gave a "non-answer" though!! Just anecdote and input from someone not trained in the fuse art. Wish I knew more and could have been more definitive.

 

Still awaiting SteveJ's wading into the fray. Maybe he's got the kung-fu.

[Zed Head]

I'm going to guess that fusible links are just the slowest of the "slow-blow" fuses.  They all work on the same principle, amps cause heat, too many amps cause melting.  The only question is how fast do you want it to melt.

[wheee!]

Well, if the fusible links are 4x smaller gauge than the supported circuit, it's going to protect it regardless...

[TomoHawk]

Yup, the headlamp fusible wire (red) on my '78 looks like an 18 ga. wire, and it's got a potential 20A to go through it.  You wouldn't want it to 'pop' when you go to the high beams on a twisty country road, so you know those things are really tough stuff.

 

The same is for the fuel injection fuse links (but I can't think of why you need three.)  The (black) one for the cabin main & accessories supposedly handles 100A,  and it looks like a 14 ga wire.

Edited October 1, 2015 by TomoHawk

[wheee!]

Picked one of these up this morning. Looks like it should do the job just fine. I'll make sure to get the appropriate size ANL fuses too.

Sent from my iPizzle ringy dingy device....

[TomoHawk]

I dunno what kind of fuses it uses, but if you paint it to match, it shouldn't look too bad.

[wheee!]

Parts arrived today. Works pretty good and I have installed some test fuses that are the flat metal style. They should act the same as fusible link wire. Need to source more accurate fuse rating fuses.

Voltage indication is accurate (according to my digital power supply) and fuse integrity LEDs work good too.

Voltage indication goes out in about 30 seconds of inactivity of current draw. LEDs stay on but draw near to zero amps.

Sent from my iPizzle ringy dingy device....