Printable Version of Topic

Posted by: Billy Bumpsteer Nov 4 2023, 12:06 PM

Completely standard 2.0 1974 car with D jet, I have just replaced the dizzy with 123 version 4RVIE, old dizzy was a 0231 174 005

Question 1, what is the best setting for the flip switch?

Question 2, old dizzy had 2 vacuum hoses on it (one from top of throttle butterfly, one from below), 123 dizzy has only 1 port, what do I do?

TIA

Posted by: 914_teener Nov 4 2023, 01:39 PM

In my opinion the 73 2.0 setting. Use the vaccum advance port on the dizzy to PORTED vaccum port on the TB if you have a port on the TB. If you don't try and find a 2 liter TB that does.

Forget the timing retard port...just plug it at the source.

Set the static timing and set the dizzy up per the instructions. Your'e done.


Edit:

To know which is ported vaccum and which is manifold vaccum...the ported vaccum for advance is on the atmosphere side of the TB plate.

Posted by: Billy Bumpsteer Nov 4 2023, 02:21 PM

Great, thanks for the answer, I will plug the hoses as I normally wait for 15 minutes before I drive off anyway

Anyone have a switch setting the can advise me to use?

Posted by: emerygt350 Nov 4 2023, 02:29 PM

You want the port closest to the dizzy attached to the dizzy port. It has nothing to do with warming up the motor. That is for efficient running at cruise. Plug the port facing the back of the car, that was for the retard.

Setting wise, choose the 73 2.0 with advance.

Posted by: emerygt350 Nov 4 2023, 02:34 PM

I believe that is setting 1 but you need to double check the manual.

https://123ignition.com/product/porsche-4-r-v-ie/

Posted by: emerygt350 Nov 4 2023, 02:35 PM

It isn't the end of the world if you plug both, but there are all kinds of good reasons to have the advance.

Posted by: 914_teener Nov 4 2023, 02:41 PM

https://123ignitionusa.com/porsche-with-d-jet-912-914-356-vw-411e-412e-1600e-type-3-4-123ignition-distributor-switched-w-bosch-d-jetronic-includes-spacer/


Your answer is in the chart down lower on the page.

Posted by: Billy Bumpsteer Nov 4 2023, 04:34 PM

So is it 9 or 0

Posted by: 914_teener Nov 4 2023, 05:16 PM

I believe the asterisk indicates using retard or manifold vaccum on the TB thus a different curve.

I'd run ported advance or 0 for a two liter. I ran that for a stock 2 liter car without issues. I ran it with advance ported vaccum.

Per the instructions.....you need to set the static timing first and you will add the static timing degree (BTDC) to the degree value on the chart.

Download the manual but I believe that's what the asterisk means.


Edit:

If the car wont' run very well with the timing set at spec static timing....you have a vaccum leak or the idle and air mixture needs to be adjusted to get it to idle at the chart RPM or spec RPM.

You need a degreeable timing light and a tach or you'll have to stare through the back window to know what the RPM are.

Posted by: Billy Bumpsteer Nov 5 2023, 08:00 AM

Quick up!

Timing checked and dizzy set to position 0

Car start so strongly now! No bucking or jumping between 2 -3K, feels like a different car, must have found 25% more power

123 distributors do what everyone says they do

Posted by: emerygt350 Nov 5 2023, 02:39 PM

Yeah, they are pretty awesome. Well worth every penny.