Distributor change

Distributor change

Ric Woroniecki
Ric Woroniecki

March 11th, 2008, 12:25 am #1

The vacuum advance on my 86 Bertone x1/9 (fuel injected 1500) isn't working & I'm failing emissions. I have a distributor from a 78 1300 carborated X1/9 that seems okay. They look similar. Can I just swap the whole assembly?

Ric W
Atlanta
86 Bertone X1/9 & 80 Fiat X1/9 & other toys....
Quote

Joined: September 25th, 2004, 5:43 am

March 11th, 2008, 1:01 am #2

Hi Ric,

The 86 uses electronic ignition and the 78 1300 was the old points style set up. I don't think a straight swap is possible. The distributors are physically interchangeable, but I don't think the 86 FI engine will fire properly.

Matt Brannon has a NOS vac adv module listed on his website. He might have a distributor on hand as well, wouldn't hurt to ask if you need to get a proper FI dizzy.

Hopefully, someone with a more definitive answer will come along soon.

Good luck!!

jd


Code: Select all

        1978                1986  \
[/b]
2005 FFO Photo Gallery
Last edited by JimDecker on March 11th, 2008, 1:01 am, edited 1 time in total.
Quote

Joined: August 6th, 2005, 6:03 pm

March 11th, 2008, 1:44 am #3

The vacuum advance on my 86 Bertone x1/9 (fuel injected 1500) isn't working & I'm failing emissions. I have a distributor from a 78 1300 carborated X1/9 that seems okay. They look similar. Can I just swap the whole assembly?

Ric W
Atlanta
86 Bertone X1/9 & 80 Fiat X1/9 & other toys....
Preformance wise, the 79+ electronic distributor will be the winner.

You can run the 78 distributor with a 78 coil, and that will require a wiring change to get the later tach to work.
Quote

Joined: September 25th, 2004, 5:43 am

March 11th, 2008, 2:35 am #4

but that's what I am known for!!

Damon. Here is my question... What about the injectors? I was thinking taht they fire off one of the wires that run from the ECU and dizzy up to the coil. Would this setup still work with a non-electronic dizzy and a 78 coil?

I am talking these two wire that are joined on a piggy-back:


Then hook to this terminal on the coil:


Looks like this:


What do you think? I am really curious as to exactly how these things work.

Thanks!


jd


Code: Select all

        1978                1986  \
[/b]
2005 FFO Photo Gallery
Quote

Joined: August 6th, 2005, 6:03 pm

March 11th, 2008, 3:56 am #5

You are correct. The ECU does time the injector pulses from the igntion system. That signal comes from the negative side of the coil. Since it's the negative side of the coil (I wont go too geeky here) the ECU should be fine "reading" any coil.

Worthy to note the coil controls the injection, but the electronic ignition module controls the tach.

I'm not 100% sure if the tach is the same on all cars. But based on the sucess of a few gauge cluser swaps out there, I think any of the 3 tachs would work if it was fed from the same spot.

Hope that cleared it up a bit.

From the glass lined tanks of old Bertone

Quote

Joined: September 25th, 2004, 5:43 am

March 11th, 2008, 5:16 am #6

I was more worried that the injectors wouldn't fire because the required signal came from the dizzy thru that piggy-backed wire to the ECU. I wasn't sure that the points style dizzy had a similar wire. If I have this right, you are saying that the ECU just needs connection to the coil to fire the injectors. Correct?

Thanks again.


jd


Code: Select all

        1978                1986  \
[/b]
2005 FFO Photo Gallery
Quote

Joined: December 29th, 2005, 6:30 am

March 11th, 2008, 5:53 am #7

Preformance wise, the 79+ electronic distributor will be the winner.

You can run the 78 distributor with a 78 coil, and that will require a wiring change to get the later tach to work.
The bosch unit has vacuum advance.
The Ducellier (pre-79) has vacuum RETARD.

Usually when ignition timing causes you to fail emissions, it's because you are too far advanced..... In which case the vac advance wouldn't be the cause of your problems. (unless it's an IM240 test - is this a dyno test or a static emissions test?

Quote

Ric Woroniecki
Ric Woroniecki

March 11th, 2008, 12:11 pm #8

The vacuum advance on my 86 Bertone x1/9 (fuel injected 1500) isn't working & I'm failing emissions. I have a distributor from a 78 1300 carborated X1/9 that seems okay. They look similar. Can I just swap the whole assembly?

Ric W
Atlanta
86 Bertone X1/9 & 80 Fiat X1/9 & other toys....
Thanks. I was trying to make life easier, not harder, & was hoping the 78 might just swap out.

I also have an 80 that doesn't require emissions in GA, so I may just swap it out to pass until I get a replacement vacuum advance.

Thanks for the info.

Ric W
Quote

Joined: August 6th, 2005, 6:03 pm

March 11th, 2008, 2:54 pm #9

I was more worried that the injectors wouldn't fire because the required signal came from the dizzy thru that piggy-backed wire to the ECU. I wasn't sure that the points style dizzy had a similar wire. If I have this right, you are saying that the ECU just needs connection to the coil to fire the injectors. Correct?

Thanks again.


jd


Code: Select all

        1978                1986  \
[/b]
2005 FFO Photo Gallery


The wire that feeds the ECU is the same wire that triggers the coil, regardless of how the coil gets triggered.

A points disty will fire the coil directly, but an electronic will signal the module and that module fill fire the coil

In a typical auto ignition, the coil is held to +12 always, and the groud connection is switched momentarilly to generate a spark (skipping geek stuff here). When it's not grounded through the dist points (or module) that terminal on the coil floats back up towards +12V. The ECU only fires the injectors when the - terminal of the coil is truly at ground potential.



Definitely not every ECU in the world, but that is the case for the bosch L-jetronic as found in these wedgies. And of course, you need the correct connection at the coil

From the glass lined tanks of old Bertone

Quote