Twin Spark Interest?

[biomimetic]

I'm not sure if as a noob I'm allowed to do this. So delete this if not.

I know people (Alfa Romeo aftermarket specialists) who make specialized cam covers, and other bits for engines for twin sparking.

The SR20, being a DOHC 2000cc engine, is in many ways perfect for twinsparking. There are also a few issues like the coil pack/distibutor arrangement and valve openings, plus fuel regulation. All twin sparks have this issue. I'm not sure how well it would work with the turbo, although in theory there should be no serious issue. In many twin spark kits it results in a 20 to 30 bhp boost. It also allows the engine to run cleaner and more safely at higher rpm.

I would maybe be selling these, but more likely would work ask a third party if they would be interested in making them on an ongoing basis. I will also post this in the SR20 forum.

Generally the kits are conversions, that are easily rec-onvertable to stock, so no smogging worries.

Would anyone have any interest in me finding out what would be involved in an SR20 (includes roller rocker guys like myself) twin spark kit?

[apoc987]

Originally Posted by biomimetic

Would anyone have any interest in me finding out what would be involved in an SR20 (includes roller rocker guys like myself) twin spark kit?

id be interested. id also be interested in finding out what the hell twin sparking is. maybe you could enlighten us, or atleast me.

[enohand]

dont some alfa's come stock twin sparked??, also i doint know how the sr would like that.....as everyone knows its real touchy & u go in there making a bigger fire it might come back & bite ya on the azz (im not sure im just throwing & seeing whats sticks)

[jasezero]

Doesn't the MSD 6A ignition do something similar or am I just thinking of something else...

[trbobrk]

It's two sparkplugs per cylinder, I think they had it on the 155.

I don't see how you would do it with creating a new head.

[jasezero]

Originally Posted by trbobrk

It's two sparkplugs per cylinder, I think they had it on the 155.

I don't see how you would do it with creating a new head.

Ohhh gotcha...that makes more sense.

[biomimetic]

Basically you get a new cover with two holes per cylinder, and eight wires, and sometimes two distribs. No cars that I know of come twin sparked although Ducati motorcycles do, BMW makes a kit for their cycles as well. It is street safe on Alfa's but definitely crosses over into track purposes. It's a good question about heat and the engine block, I will researcha a little. Anyone else? If I get to ten or twelve I'll make some phone calls...

[miamig20]

ive seen older datsun models with this too.

[p10det]

the old 200sx's had 2 plugs per cyl

[miamig20]

yeah my cousin had a starlet hatchback with one of those engines datsun 240 engines and it had two plugs,. That car really hauled ass too.

[markbuts3]

Originally Posted by biomimetic

Basically you get a new cover with two holes per cylinder, and eight wires, and sometimes two distribs. No cars that I know of come twin sparked although Ducati motorcycles do, BMW makes a kit for their cycles as well. It is street safe on Alfa's but definitely crosses over into track purposes. It's a good question about heat and the engine block, I will researcha a little. Anyone else? If I get to ten or twelve I'll make some phone calls...

As Colin said, you need holes in the head too, there's no room in the combustion chamber for another plug. It's pointless having an extra hole in the cam cover and only one hole in the head

[biomimetic]

Yeah, I know, and maybe different valves/springs depending on heat, etc. Alfa' s say, are dromic chambers; I wasn't aware of twin sparks for 200 series Nissan's, but I'm not surprised. Seems like how much room is always an issue, and would just be something I would have to ask about and measure for before coming up with a definitive answer. Another thing is that in all likelihood the engine would have to be run with 91 only.

[Wiggy]

had that on the old 86 nissan 720 4x4 -- and there was not increase in power its FUNCTION was to help burn any unburned gas which reduced emissions. Ford also did this with some of the ford rangers in the late 90's and the first people that did this spark plug idea was back in the packard days of the 1940's. (my grandpa would always tell me about this when i would bring the 720 over)

today its not really needed becasue look at the head design on the sr20 the sparkplug is in the middle of the cylinder the spark from the plug has a lot more energy and can ignite things a lot better than 10 or 15 years ago

just my two cents.

joe

[biomimetic]

Not sure about that Joe... interesting though. Like I said, I have not seen a newer car dyno with a twin spark, and I did say run cleaner, fire better, and in older cars the otherwise unfired gas produces more hp in significant amounts. Does anyone have any dyno stats on this for a car produced in the last 15-20 years? The 200nx or the Pulsar seem like good examples someone posted above. I would also point out the SR20 is at this point an "older" engine in your range of 15-ish years. I'm not sure that you can say that newer cars necessarily produce more spark; especially since they run more electrics, and just adding a bigger alternator doesn't really solve the issue. It was really a question for people who prefer carborated, or maybe are taking track days with other caborated cars, or want a system where they can amp up their hp in areas where they have to return to a smoggable formatted engine every year or two. On a more negative note, I know that when Porsches are twin sparked, it is a major PITA, the entire engine has to be disassambled, flipped over and drilled into and threaded with a secondary set of plugs, as well as wiring. Like I said, I know a few people, and it would just be a conversation about it. I'm counting about 2-3 yays and maybe 5-6 nays.

[markbuts3]

So where are you planning on fitting an extra spark plug ??

[biomimetic]

I'm would not be the one implementing it; would you like me to ask the people who make the kits for other cars? Or not? It's a straightforward question - if you're a turbo guy the answer is no, if you like the sound of carbs and stuff, maybe so. I'm not saying it wouldn't require extra bits. I was gauging interest, not creating a committee to re-engineer the SR20 for twin spark on the spot.

[StangG20]

its not really feasible. i dont know how they do this on other cars but its definitely not feasible on an sr20 and i know the hassle would definitely outweigh the gains.

[markbuts3]

Here's a hemi design with twinspark...

One problem that cropped up after the decision to adopt the twin-spark design for the Hemi: The basic architecture of the Hemi head meant that the two spark plugs had to be situated slightly offset from one another, which adds a step in the machining of the head. "That cost a couple hundred thousand dollars," laments Lee.

Sorry but I don't see a way to get two spark plugs in there without redesigning the complete head and probably the pistons too. It would be very expensive. The plug as it is, is positioned in the optimum place.

Ask if you like but not on my behalf, I'm not gonna spend a fortune on a 12 year old engine.

[trbobrk]

I agree with most of your comments about how impractical it is to make the SR20 a twin spark engine. I do enjoy seeing people do something new, or implimenting a far out idea just to see what happens. Twin spark does have a real world application, most all airplanes have dual ignition systems, and pretty much everything important to the running of the engine are redundant. Reason being, when the engine quits or even just loses some power, whatever you are looking down on is where you are going to land. For a car when the engine quits, you call a tow truck.

If you want newer technology in your SR20, get distributorless coil on plug, variable valve timing, drive by wire, etc.... hmm sounds like a 20v to me.

[biomimetic]

I think this is where I am coming down as well. Bigger injectors, a fuel regulator, bigger fuel pump and the upgraded cams would be required *if* you could drill and thread a double hole into the space. I wasn't meaning to imply variable timing and turbo wasn't easier with the SR20. But I have seen twin sparks in a long narrow inline six (Merc and BeEm from the '80's), a worse space with original holes equally difficult to enlarge - but they don't have ECU's controlling firing (as far as I know). In the idea's favor is that some of the same parts are in the Infiniti as you might find in one of those. If the SR20's are coming onto the market as used replacement engines, and someone was interested, it's an interesting experiment I think, if there's an extra block around, and as long as you have someone who can drill and thread the block, and also make you a valve cover from billet. But with the variable timing at the ECU, you would have to disable knock sensors, eliminate the redline cap, and I'm not sure that the JWT ECU would work with the system. It might be of more use for some subcategory of pure racing engine rather than bulletproof street use, I think I have to say on reconsideration.