Here's my crazy idea.

In my pursuit of increasing low end torque for offroad lugging capability, here's an idea that could work:

Rotate one camshaft 180 degrees and then alter ignition to fire that side at the proper time when it is ready. This would in effect change the firing order from the stock evenly spaced 1-3-2-4 to an overlapped order like 1/2-3/4-x-x.

What that would mean is cylinders 1 and 2 would fire at the same time followed by 3 and 4 firing at the same time followed by 2 dead strokes. It would sound like Bang-Bang-Pause-Pause. In operation it would run kinda like a small tractor, but during the firing strokes it would effectively have a surge of increased torque followed by a lag. This should allow the engine to lug at a slower rpm and not stall as easy. It may also need a heavier flywheel to keep it idling or lugging right.

 

Rotating the camshaft would be easy and I think the fuel intake and exhaust would handle it ok. The real challenge may be in altering the distributor by modifying the rotating sensor to only 2 lobes and then to somehow split the spark so it could fire two sparkplugs at the same time.

 

Sounds crazy I know, but i bet it would be fun to try.

 

Rollie

Here's my crazy idea.

In my pursuit of increasing low end torque for offroad lugging capability, here's an idea that could work:

Rotate one camshaft 180 degrees and then alter ignition to fire that side at the proper time when it is ready. This would in effect change the firing order from the stock evenly spaced 1-3-2-4 to an overlapped order like 1/2-3/4-x-x.

What that would mean is cylinders 1 and 2 would fire at the same time followed by 3 and 4 firing at the same time followed by 2 dead strokes. It would sound like Bang-Bang-Pause-Pause. In operation it would run kinda like a small tractor, but during the firing strokes it would effectively have a surge of increased torque followed by a lag. This should allow the engine to lug at a slower rpm and not stall as easy. It may also need a heavier flywheel to keep it idling or lugging right.

 

Rotating the camshaft would be easy and I think the fuel intake and exhaust would handle it ok. The real challenge may be in altering the distributor by modifying the rotating sensor to only 2 lobes and then to somehow split the spark so it could fire two sparkplugs at the same time.

 

Sounds crazy I know, but i bet it would be fun to try.

 

Rollie

 

If you could get opposing cylinders to fire simultaneously it might not shake itself to death but you'd need a whopping flywheel and a big balancer. Truthfully having just a whopping flywheel will help with lowend torque without going to the harley like two cylinder running. If you went stand alone coil on cylinder ignition or wasted spark you wouldn't have to worry about fabbing a double ended rotor - not sure that would even work as the spark would end up going to the cylinder with the least resistance. So I think you'd have go go with a coil on/wasted spark.

 

I'd be interesting and anything is possible but not sure that the ROI is there.

 

Thanks

Renny

harley like two cylinder running..... So I think you'd have go go with a coil on/wasted spark.

 

So Harleys share a single crankshaft rod journal for both pistons resulting in uneven firing?

 

I think if we can simply come up with an ignition system, this idea could be easily tested. Could you explain more about your ideas and "coil on/wasted spark?

 

Rollie

"Bang-Bang-Pause-Pause"

 

 

Hmmmmm kinda reminds me of this sound from an old movie ....

 

 

"Chitty-Chitty-Bang-Bang"

 

Sounds interesting tho, I'd like to hear about the possibilities of the heavyer flywheel, too since this sounds easy to try ... would the hvy flywheel cause conciderable wear on the crank shaft/engine in general? Or is it a "safe" mildly intrusive mod ...

In a COP (coil-on-plug) wasted spark system, each plug has its own coil. The coils are fired in pairs, so that each cylinder fires on the compression and the exhaust stroke. The plug firing on the exhaust stroke is the wasted spark.

Rollie thats a great idea lets do it

Sounds to me like your'e asking for a broken crank, not a lot of beef in there.

if a coil from a ej22 will help youguys i can provide one for this project along with the ignitor...

what about the wasted fuel washing the non firing cylinder?

 

Jim

you'd rattle that motor to pieces in 20 minutes.

what about the wasted fuel washing the non firing cylinder?

 

Jim

 

It would probably be easier to do with an MPEFI reprogrammed for the new timing sequence. I have NO idea how that would happen though...

Some how I see the _pause_pause_ part loading up to be backfired like a cannon. Wouldn't the crank need to be offset some to stop it from wanting to go backwards/destroying itself? I'm not saying it can't be done, but it sounds painful.

 

Here is a link to a low RPM opposing cylinder motor, maybe you can look into how they accomplish it.

 

 

http://www.jabiru.net.au/

 

These motors have tons of torque, and are made to run around 1500-2000 rpm without a reduction gearbox/massive flywheel. I have played with the 6 cylinder version myself, and it's a work of art.

 

Fishums

Some how I see the _pause_pause_ part loading up to be backfired like a cannon. Wouldn't the crank need to be offset some to stop it from wanting to go backwards/destroying itself? I'm not saying it can't be done, but it sounds painful.

 

What they are talking about doing will work, each cyl will still fire just as they did before, only two cyls will be fired at the same time. Then after the crank shaft has rotated 180 then the other two cyls will fire. Then the crank will rotate 360 to get back around to fire the first two cyls again. I think the wasted spark part got some people off track. Most single cyl 4 stroke lawn mowers use the wasted spark method. This is where the ignition system is connected to the crankshaft instead of the cam. The ignition fires a spark every time the piston reaches TDC. The problem I see with this arrangement is that there will be two power pulses hitting the crank at the same time, not too sure if the crank and bearings can handle the load. It still would be fun to try it just to see how it runs.

I appreciate all the responses so far. The encouraging ones make me think it just might work. The predictions of doom encourage me also to see if I can prove that it really does work. In either case it all generates enthusiasm for what should be a fun project.

 

I'm thinking of picking up a cheap doner car that already has a running engine and giving it a try. Probably an EA82 because that is what we are running in all our other projects. At this point, the immediate challenge I see is how to get two sparkplugs to fire at the same time. As for the "wasted spark" issue, I see that it shouldn't really make much difference either way.

 

Edits Added: As for increased load on bearings, each rod bearing will still be the same as before. As for main bearings, since the two cylinders that fire simultaneously are on opposite sides or opposing each other, it should actually have a cancelling effect and reduce the side loads on the main bearings. However during the firing strokes, there would be an increase of torque on the crankshaft which is part of the whole reason we are doing this in the first place.

The other challenge I see coming and one of which I have no experience with is balancing and flywheel weight. I really have no clue how it is going to run, until I try it and see what happens.

 

Thanks for the input

 

Rollie

That's pretty cool, hope it works. Would definately be a sweet accomplishment.

 

For the electrical is there anyway to rig up a second, rotor and cap.. on a second coil above the exsisting rotor cap? It would require some real rigging :-p but could work!

EA82 with timing belts. the EA81 wouldnt work unless you made a new cam , its pushrod

I think this is a cool/funny idea! You're actually trying to make a Subaru engine into a Johnny-popper! For those who do not have agricultural backgrounds, a Johnny-popper is an old 2-cylinder John Deere tractor. They were inline-2 motors and went Bang-Bang-pause-pause. Deere quit making them a LONG time ago. They were not a smooth engine

 

For this project, what will this help? I understand that the instantaneous torque at firing will be doubled (is that okay for the EA crank and transmission?), but the power output will be the same as the engine runs. Will this help with low-rpm pulling ability? Off-hand I'm not seeing how it will.

 

Good luck with this. I hope you get it to run and have a lot of fun!

I guy at work has a nissan pickup with dual sparkplugs a Z motor this is the cap

 

 

 

 

it uses 2 coils and this funky cap with 2 coil wire inputs

we can make it work

I guy at work has a nissan pickup with dual sparkplugs a Z motor this is the cap. it uses 2 coils and this funky cap with 2 coil wire inputs

we can make it work

Grab that cap and rotor. Maybe we could modify then to fit on the Sube.

Nice, that looks like the ticket. Hows progress coming along btw? Find yourself a motor yet?

I would suggest taking a look at a Rotory engine, they use two coils for a simotaneous spark(two plugs per rotor). Might help, just a thought.

 

Clayton

Hows this thing coming along btw? I've been curious to see how you made out with it.

I used to have a 82 datsun pickup that used the double coils and 8 plugs. If i remeber right one plug is set to fire a little advanced and the second retarded. It was vacume controled and when you opened it up it was supposed to cut one the plugs to change the timing. Just so you know.

 

David

I used to have a 82 datsun pickup that used the double coils and 8 plugs. If i remeber right one plug is set to fire a little advanced and the second retarded. It was vacume controled and when you opened it up it was supposed to cut one the plugs to change the timing. Just so you know.

 

David

 

i've worked on one of those pickups. there are 4 plugs on the intake side and four on the exshaust side. the four on the exshaust side are for emissions. they are suppose to burn any thing that didn't burn on the firts set. this is what i was told by many people, couple of them had owned these trucks

ready to hit this again got the car ( Blue Bomber) picking up a nissan disty , if I could do it without swapin distys i would prefer that,