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Discussion Starter · #1 ·
I have a 1992 Vw Cabriolet that im carb swapping because the wiring harness is melted. The car was given to me so im its last chance. Its a a Digifant 2 car and i need spark. I have gathered info here but need to sort out some thoughts...


IGNITION

1. The Digifant ignition setup cant be wired with just a icm like i found diagrams for on the "running a 6al and no stock stuff thread" can it?

2. I believe 2 of the wires going to the icm go to the ecu on digifant so i would need a cis car harness if i wanted to run just a icm to get spark.

3. On the "running a 6al and no stock stuff thread" it shows a diagram for wiring a 6al in conjunction with a Daytona timing system TCS-1 and icm. "Why cant i wire a 6al-2 with a cis icm and use my Digifant distributor. From what i have found the 6al-2 works with haul effect distributors and has adjustments for timing on the box. Would this setup work "MSD 6AL-2, ICM, STOCK DIGIFANT 2 DISTRIBUTOR THAT CAME IN THE CAR" I would like to run a points distributor green wire only but im not sure if i can and i cant find one online.


FUEL

So can i run my transfer pump thats in my tank and delete the high pressure pump under the car and regulate pressure under the hood with a FPR with a retun line?
i feel like this would be a clean looking way to do it. if i have a pump in the tank why do i need to put a inline pump also it seems redundant. would this setup work"STOCK IN TANK TRANSFER PUMP, SOLID PRESSURE AND RETURN LINE FROM TANK TO FIREWALL WITH NO UNDER CAR PUMP, FUEL PRESSURE LINE INTO REGULATOR, BYPASS PORT ON REGULATOR BACK TO THE RETURN LINE"?

So far i have a VW 055129713K intake with a carb adapter and a holley 2 barrel. i paid 150 cash for the carb and manifold,

I received Techtonics tuning injector plugs today instead of the change and silicone. Thanks for reading any input would be appreciated!
 

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If you only run a stock distributor and icm, you end up with locked timing. The "easy" button for you would likely be to swap in a cis 8v distributor that has the mechanical/vac advance. The other option would be to to run some sort of timing computer (cis-e knock box, aftermarket like a megasquirt or other programmable option).
 

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Discussion Starter · #4 ·
Thanks for your input!

Okay so i've taken the plunge and ordered some fire starting devices!

MSD 6AL digital
vacuum advance distributor new 1985 era
distributor connector/pigtail
icm
icm connector/pigtail

Going to use the coil that was in the car.

I think this will work. See anything wrong with this setup?

Wiring the 6al digital with the factory icm and using the vac advanced distributor.
 

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Why do you need the MSD? You just need the ICM and distributor from a CIS car without a knockbox. DO a google search. You will find the wiring diagram with literally 6 wires to get your car running If you really want to run a points ignition setup like I did you need a points ignition coil too. The points coil has a built in resistor to keep the points from burning out. I got mine from BusDepot.com. I cant remember what year but many of the buses uses points. . Also I ran a 2bbL carb on my 92 cabby. It need 8psi of pressure at all times. Run the stock fuel pumps with the a holly by-pass fuel regulator. The holley regulator is set to 8psi from the factory.


Found the link for the points coil

http://vwparts.aircooled.net/12V-Bosch-Blue-Coil-with-Mounting-Bracket-00-012-p/00-012us.htm
 

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Discussion Starter · #7 ·
fuel pressure info for carb swap.

Just some cool fuel info that might be useful for a carb swap...

Digifant two in tank pump produces 300 ml in ten seconds, thats 30ml per second.

30ml per second = 28.53 gallons per hour (GPH)


MR GASKET 42S= 2-3.5 PSI and 28(GPH)

MR GASKET 12S= 4-7 PSI and 35 (GPH)

HOLLEY 12-426= 1.5-4 PSI and 25 (GPH)

HOLLEY 12-427= 4-7 PSI and 35 (GPH)


I have noticed people delete the high pressure pump and replace it with one of the above listed in line fuel pumps.

Maybe there is something that i don't realize but it seems to me that the cleanest way to accomplish 3 to 4 psi for a webber swap would be to run the in tank pump and

bypass the high pressure pump and use a wix 33041 under the hood to supply fuel return.

The wix 33041 has additional return outlet that should prevent vapor lock.

I found a post about this filter and setup claiming that it provides 3.5 to 4 psi and needed to verify as best as i could before trying it. I hope this clears up any questions one would ask themselves before taking the plunge!

In theory i don't believe you would need a fuel pressure regulator.
 

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Discussion Starter · #10 ·
Garryt

intresting, what would my advantages be and why wouldn't the stock 93 cabriolet tank setup be as good? Also what mk3 tank would fit into a cabriolet? Would the pump access hole in the cabriolet be large enough to remove the pump with the mk3 tank in the car? Or would you need to drop the tank to service the pump after a mk3 tank swap? I'm Interested in what you have to say. What is the pump reservoirs purpose as far as how it would be better.

Ez wiring harness showed in the mail today so if I'm using a diffrent pump I gotta figure this out haha. Going to re pin connectors rather than cut and splice connectors pigtail style.
 

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you need the reservoir in the tank (if your deleting the main pump/reservoir) to keep a certain amount of fuel at the pump inlet during steep climbs/descents on hills or during long cornering. more likely for the pump to run dry if your level goes below about 1/4 tank. you could even make up a small reservoir to fit the original tank pump. an old food tin with the right amount/size of holes drilled in it:)
 

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Discussion Starter · #12 ·
I see what you mean;) My previous post was about keeping the pump in the tank and removing the pump under the car. I believe we are both on the same page as far

as the in tank pump.

I could understand how only running the pump under the car could cause an issue with slosh and low fuel levels. Haha i hope we are on the same page.

Im running the cabriolet in tank pump setup as is.

Im not removing it and using a Mr Gasket or Holley under the car.

As i understand it the stock in tank pump setup flows 300 ml in ten seconds which is 28.5 GPH to the under car pump.

Im not saying the car drinks 28.5 gallons per hour lol rather that the in tank pump would fill a swimming pool at that rate.

The in tank pump feeds the under car pump. Then the under car pump pushes 3 bar at the fuel rail on a digi two car 3.5 depending on the vacuum applied to the fuel pressure regulator.

My thoughts are that if the in tank pump as is has been supplying the under car pump with fuel under low fuel conditions and cornering for 27 years, than it should be able to feed the same 28.5 gph under the hood into the wix filter with return bung thus eliminating the need for a Mr Gasket or Holley pump under the car.

Im not absolute on 3.5 to 4 psi under the hood with this setup but jettaboy1884 claims thats what it feeds a webber 32/36. I will see as soon as i get my kit k402 in the mail. Ditching the Holley and Scirocco intake backwoods setup i got cheap for simplicity. The holley is old and the gaskets are dried up amongst other things. im not running coolant to heat the intake either so the vw 005 129 173 k intake looks ugly with the heater hose attachments. also the webber kit comes with linkages and such.
 

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you are right enough, but you need to bear in mind that the main pump has a reservoir which maintains enough fuel to keep the engine fed. I suppose either way you look at it, the in tank pump could run dry occasionally for a few seconds, but it wouldn't show up at the engine due to the reservoir/main pump under the car. a fuel pump running dry for any amount of time is never a good thing though. if you live in a relatively flat part of your country and you keep your fuel level above 1/4 tank at all times, it will probably work fine for you as is:thumbup:
 
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