12V V6 Engine Distributor Types

Started by Fylnn, April 02, 2013, 03:19:17 PM

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Fylnn

I am trying to understand what types of distributors fit the 12V V6 from the rear drive cars.  My problem is that I am running a Haltech computer which was using the electronic trigger in the original distributor from an 83 GTV6.  This worked well enough for a while but for various reasons the electronic triggering device seems to have fried.  The rotor button did some apart and the might have shorted something out, but since I replaced the rotor button the car has developed a very bad miss under load and when it is hot. Once the engine is warmed up you basically can't drive it.

So I need to come up with a new and reliable trigger mechanism.  One idea from the guy who installed the Haltech is to use some Nissan trigger wheel inside the distributor but that then necessitates a switch to multiple (3 or 6) coils which gets a bit messy space wise, not to mention expensive. 

So I was wondering what the later cars, 75's for instance ran that might be able to be substituted.  Better still someone like Centreline offer a replacement pickup.
https://www.centerlinealfa.com/ignition-system/1301
Does this look familiar to anyone?  In a perfect world then I would get a later distributor, put a new pick up in it, and then it should be reliable and should all work without major changes to multiple coils etc. 

Fylnn

Update on this.  Got the distributor from Ben out of a 75.  Stuck it into the GTV6, took it down to the Haltech guy.  He was much more excited about using the Hall effect than the reluctor.  So all connected up and away we go.  Engine strong again, no hints of the intermittent misses and fluffing that has been plaguing it for the last year or so. 

105gta

That's great news! Glad to hear all is well now, hope to see some shots of the car in action!
Ben
1967 Giulia Sprint GT Veloce (WIP)
1985 GTV6 (WIP)

Fylnn

Off to do some testing the weekend after ANZAC Day, so hope to get some photos at last. 

GeeTV

Flynn - Did you receive any feedback regarding the Centeline electronic pickup?
https://www.centerlinealfa.com/ignition-system/1301

AND for an 84 gtv6 can anyone tell me which rotor 'should' be factory fitted & if these are interchangable? [Pic attached borrowed from Shiny_Car]

martym00se72

one on the right I think. The one on the left has built in rev limiter fitted to earlier versions...
'83 GTV6 - 3.0 is in! Ohhh yeah!
'99 156 T-spark - Formula 98 ready!

What do people do with their old 2.5...?

GeeTV

Thanks for that MM72 - Although your reply raises further questions.
Why does my 84 gtv6 [seemingly stock], have a rotor like one on the left?..... Is it just a straight swap to the one on the right?

martym00se72

It sure does as my 83 has one like the one on the right...
'83 GTV6 - 3.0 is in! Ohhh yeah!
'99 156 T-spark - Formula 98 ready!

What do people do with their old 2.5...?

Fylnn

I never did get any feedback about the Centreline kit.  In the end I got a later model distributor out of a 75 with the hall effect pickup and fitted that.  It worked much better with the Haltech. 

As far as I can work out, the one on the left with the rev cut-out was on my 1983 model.  I tend to think that the one on the right without the cut out is off the 75's. 

scott.venables

The one on the right looks the same as what's in my L-Jetronic 75

105gta

Yeah Flynn, I'm 99% sure your are correct on that, the early reluctor ignitions had the rev limiter built mechanically into the rotor button, (centrifical arm that literally shorts out the spark) then when they went to the Hall effect dist with no mechanical advance mechanism, the rev limit was built into the electronics. I believe it was to save the ignition module circuitry from excess voltage from the reluctor, which generates more voltage with revs, approx 100V nearing rev limit speeds. It Would mean much more complicated (read expensive) circuit boards to cope when the signal was still coming in but not being used. With Hall effect fixed at five volts it is easy to deal with ;)
1967 Giulia Sprint GT Veloce (WIP)
1985 GTV6 (WIP)

105gta

Sorry, To answer some earlier questions, yes the 2 rotors are interchangeable, the ignition module in the earlier reluctor system proved over the years to be fairly robust, plus there is a built in rev limiter to the fueling computer as well so unfortunately you won't gain much by fitting the later rotor button as there comes a point that the poor old L jet can't cope and doesn't have the capabilities to dispense fuel at higher speeds. Essentially the 2 distributors are the same unit but the earlier unit (all gtv6 as far as i know) has reluctor type ignition (6 pointed star under rotor) with mechanical advance, while the later (alfa 75) had Hall effect ignition and advance is comtrolled through the electronics along with rev limit.
You may save couple of dollars with the later rotor due to simpler construction, minimal but gain reliability due to less moving parts not that the early type has proven unreliable. Both my 75 and gtv6 are 1985 models with the differing ignitions. Which I thought was strange as the gfv6 has the later short torsion bars and isostatic gear linkage but didn't get the revised ignition.
1967 Giulia Sprint GT Veloce (WIP)
1985 GTV6 (WIP)