Distributor for dual plug head.
 

I have heard that there is an easily obtainable distributor for dual plug head. Who knows what it is?

Re: Distributor for dual plug head.
 

I do as run one , 80.s nissen , pos have a spare , two models , points or electronic , hard to find out here in NZ ,

Re: Distributor for dual plug head.
 

Here is everything you need to know:

https://www.mtfca.com/discus/message...tml?1515095768

Re: Distributor for dual plug head.
 

Those are some pistons in that Frank Harris post!

Re: Distributor for dual plug head.
 

Except for reliability there is no need for dual plugs in a normal flathead Model A. The turbulence is good enough so that the flame burns quickly. An engine with overhead valves would benefit. Or a large T head engine.

Re: Distributor for dual plug head.
 

For a Pietenpol maybe? They could use a magneto drive of one side and battery for the other.

Re: Distributor for dual plug head.
 

I have a distributor set-up that I think is pretty cool in that it uses an Early V8 Ford distributor mounted onto a Model-B distributer housing. An E. V8 distributor is basically a dual-ignition 4 cylinder distributor. If I recall correctly, the Nissan Distributor is set up for a leading/trailing timing application, -and if so, some of the performance advantage is lost.

Re: Distributor for dual plug head.
 

Would love to see some pictures of that.

Re: Distributor for dual plug head.
 

My head is an OHV Dual Plug head.

Re: Distributor for dual plug head.
 

The divers helmet type distributor has a cap for each side with a spindle type rotor that feeds both caps. They used one set of points to break the induction circuit and the other set of points closes early to increase dwell time for the coil. There have been several dual coil type aftermarket distributors that were made for performance on V8 engines and I've seen several dual fire set ups made from V8 and V12 type distributors. It has been done for bangers I'm sure but they were rare and parts can be unobtanium for some.

Re: Distributor for dual plug head.
 

Thanks for the information. I am now on the hunt for the Datsun distributor.

Re: Distributor for dual plug head.
 

The Nissan twin-fire unit I'm running on my BB RAJO fires the exhaust 4 degrees after the intake fires, I believe. I have my fuel pump wired into the intake side of my switch and when all 8 are firing, when I "clip" the exhaust plugs, you can very much hear the RPM drop !

Re: Distributor for dual plug head.
 

Chis , I have a spare one in NZ if can,t find closer,

Re: Distributor for dual plug head.
 

Re: Distributor for dual plug head.
 

The RAJO head that Stevests talked about in Post #12 will benefit from dual plugs because of lower turbulence in an overhead valve head.

The head that Brad showed in Post #14 is a gimmick. The extra plugs will do very little if anything to improve combustion. I would use the plugs that are over the intake valves, where the air/fuel is fresher, and just keep the other 4 plugs in there to plug up the holes.

Re: Distributor for dual plug head.
 

Chris

Does this twin plug head have cartridge fire on the plugs?

J

Re: Distributor for dual plug head.
 

I have no idea what that is.:confused:

Re: Distributor for dual plug head.
 

Chris,
cartridge fire is where the sparkplug is removed directly from the chamber with a small sub chamber.
McDowell, Cook etc are this way.
Over the years these heads get changed by drilling out the port or moving the plug directly to the chamber.

As someone did mention before, a single plug more than adequate to ignite the fire in the model A
We have been turning 7200 rpm in the race car on a single plug without a mag

There are many opinions about plug location in the chamber but the reality is that the ex valve opens first and if the flame front starts there it may not make it completely to the opposite side. Take a look at the Brierly head and plug location, it makes a lot of sense.
John

Re: Distributor for dual plug head.
 

The Brierly head is not OHV as mine is. There is one plug on each side of the cylinder. This car sat in the same spot for over 75 years. During that time the original Delco 5195 Two Cap distributor disappeared. I am just trying to get it back on the road.
What you call a cartridge fire I have always heard called a pre combustion chamber.

Re: Distributor for dual plug head.
 

Chris
Yes correct Brierley’s cyl head is not OHV
Plug placement in an OHV is typically not an option with everything

So what is the head?
If just trying to get it running after 75 years a single plug should be adequate

J