another triple weber question

[nitekillerz]

I bought my 260z with triples installed. I was able to get the engine to fire it up but only iddle. My question is, with this setup will the standard distributor left stock will vacuum connected work? I've heard triples need advanced timing in mid teens but if you do with vacuum it'll run in 40s at WOT and could detonate.

 

Below is a picture if my distributor. How do I know if it was modified already?

Edited May 10, 2015 by nitekillerz

[michael wales]

My triples have always had mechanical advance which I was told was necessary due to lack or proper vacuum.

[steve260z]

I don't know what you're saying half way through post but disconnect the vacuum. Regarding the timing, you need to use a timing light to see how much advance your dizzy has since a lot of Zs have had the units changed out over the years.Rev the car until the timing stops advancing and see how much total advance you have. This will be around 2,500 rpms or so. You'll need to mark the balancer since the markings on the metal scale stop at 20.

 

Doing this will solve your issue of wondering if your dizzy has been modified. Webers are about total, all in timing not static timing.

[nitekillerz]

So I would set the timing advance on the dizzy? How much should it be and how do I limit from going too much and detonating?

[nitekillerz]

http://datsunzgarage.com/weber/

This is where I'm getting my information on timing and triples

[steve260z]

Thats a very good site but you don't need to modify the distributor unless it has too much timing built in.

What you want to achieve is around 34 degrees total once the dizzy stops advancing and not be concerned about idle assuming its reasonable,,,somewhere above 5 degrees.

 

So, you need to find out how much advance your dizzy has currently.

1. Disconnect the vacuum from the dizzy

2. Get a fabric type tape measure, like the ones tailors use. Wrap it around the balancer to get the circumference. Say its 37cm. Divide 37  by 360(degrees). Gives you .102 cm. That tells you every .102cm is 1 degree of timing. We want to mark where 34 degrees is on the balancer. So, multiple .102 x 34 (degrees) which equals 3.49 cm. 

3. Now measure 3.49 cm to the right (clockwise) of your zero mark on the balancer. Mark it with white or some bright paint so you can see it with the timing light.

4. Rev the car while using the timing light up to around 2,500 or when the mark stops advancing then adjust the distributor so your new mark stops at the zero number on the factory timing scale/gauge/marker.

[nitekillerz]

Thats a very good site but you don't need to modify the distributor unless it has too much timing built in.

What you want to achieve is around 34 degrees total once the dizzy stops advancing and not be concerned about idle assuming its reasonable,,,somewhere above 5 degrees.

 

So, you need to find out how much advance your dizzy has currently.

1. Disconnect the vacuum from the dizzy

2. Get a fabric type tape measure, like the ones tailors use. Wrap it around the balancer to get the circumference. Say its 37cm. Divide 37  by 360(degrees). Gives you .102 cm. That tells you every .102cm is 1 degree of timing. We want to mark where 34 degrees is on the balancer. So, multiple .102 x 34 (degrees) which equals 3.49 cm. 

3. Now measure 3.49 cm to the right (clockwise) of your zero mark on the balancer. Mark it with white or some bright paint so you can see it with the timing light.

4. Rev the car while using the timing light up to around 2,500 or when the mark stops advancing then adjust the distributor so your new mark stops at the zero number on the factory timing scale/gauge/marker.

thank you for this, very useful. one quick newbie question. how do adjust the dizzy itself?

[steve260z]