OldManMoses,
Thanks for the welcome. Good info on the sidegapping. It definately unshrouds the spark. It is really hard to measure the responce from it because the flame will still travel acoss the piston without doing it this just supposed to do it faster which in turn adds more power. We have been sidegapping and indexing spark plugs for years. The reason to index is to start the burn at the point where the fuel gets out of the cylinder first eg. the exhaust side. That is where you want the flame front to start. Anyway the difference is much greater in bigger cylinders since the flame front has to travel much further. However this engine sure could respond to the change pretty well if the cylinder is not very efficient with the quench. I will also give it a try and retake my time and let you know. So far the biggest single change has been the pipe. Anyway I still have the dynojet kit to go and the lean pop at idle came back with the pipe so I need to richen up the mix at the low end. Later

 

Bmj67,
You can do it either way just as long as 75% of the tip is exposed to the cylinder and the spark is unshrouded from the electrode. We never grind the tip as it is very hard to get all of the edges cut off and they can create hot spots and give you preignition. We have always just bent the electrode up and back and then bent the tip of the electrode back down. Oldmanmoses seemed to have some luck with extra power and at 8.3 to one compression the 360 motors are not very high compression so preignition is not likey. It sounds like he got the electode polished back up just fine.

 

Hey BMJ

Go to the sidegapping link above and open it up---on first page on top right is another link that says how to sidegap---click it and there are pictures of the whole process---I used a dremem cutoff and then polished with emery cloth th remove burrs---I also gapped plug at .025 instead of the normal .035

I swear bike is running better.

Mopar Man----get your needles shimmed and lean your main jet out, you will be impressed with the power

 

hey mopar man

can you give me a little more info on indexing???
which way would the cutoff electrode (on a sidegapped plug) be facing??? The exhaust valve???

How many washers are acceptable to achieve proper indexing???? More than one washer??

 

thanks for the help. i would also like to know how to index plugs.

 

I think you guys understand, but to clarify, It was a dremel cut off tool i used to trim the electrode on the spark plug---sorry for the miss spell

 

OleManMoses
Idexing plugs is like anything else everybody has an opinion on what is the right way. I believe it is to put the open part of the plug facing the exhaust valve towards the bigger side of the piston. You want the flame to start on the exhaust side and burn towards the far side of the piston first since the exhaust side is what will be expelled first and the flame has further to travel across the piston on one side than the other. Never face the open part of the plug towards the close cylinder wall that will really shroud the spark. I am not a big fan of washers as anytime you put one on you will pull the plug out of the hole somewhat. I have always tried my best to buy several plugs and try one till it works. But if you have to the lesser the better. Moroso makes a kit to index that has several different thickness of brass washers with it. You do not just want to use any old washer as it will rust by the fuel and heat. As for the shimming I am going to try my Dyno jet kit this weekend first. I am going to try and leave the main jet alone as this HMF pipe definately leaned out the quad, I do not think I want to go any further yet. Oh and I saw the lates ATV Connection and they have a midsize quad shootout and we got second again behind that darn Bombardier. Personally I sat on one and it has way too much plastic and felt top heavy. Oh well what do they know. Oh and what tires are you running? I am thinking about going to the Kenda bounty hunter radials when they come out or the ITP mudlites. Later

 

Hey Mopar Man---thanx for the tip on indexing---another question for you if you can answer---what relationship does plug gap have with performance??? What difference theoretically speaking of course LOL should you feel between a tight gap and a loose gap??????

I am still running stock Dunflops---My best bud with a polecat sportsman 500 has goodyear trackers on his (stock) and just blows me away in the mud---I am going for new tires before winter and am considering the goodyears---also considering the mudlites

 

OleManMoses
Ahh the plug gap question. Also an age old battle of opinions. My hobby before 4 wheelers for the past 15 years has been truck pulling. We have a 900hp Mopar 4 wheel drive that we have been pretty successful with. I have tried every performance tip, trick, black magic, etc. that you could ever think of. And unfortunately very few can you tell a seat of your pants difference. So with that said I can relate you the "Never ending Quest for power" and it is the "quest" that is so much fun. What we have found out is that power gains are very hard to come by but power losses are not so what you want to be careful of is going too far one way or the other. Plug gap is one of those. Taking the common sense approach obviously "in accordance with the side gapping theory" when you have a bigger gap there is more spark exposed to the fuel mixture and more fire all at once to get the burn going. However if it is too wide it can be blown out by the force of the turbulance in the cylinder. We have experienced that, but we are running 15 to 1 compression. I do not think that would be a problem with the 360 at 8.3 to 1 With that said here is an interesting recommendation from MSD ignitions. We run one that is about $1200.00 and will knock you on your tail if you get in the wrong place at the wrong time.
UP to 10.5 to 1 50 to 60 thousandths
10.5 to 13 to 1 40 to 50 thousandths
above 13 to 1 35 to 40 thousandths
They also have this to say.
A large plug gap taxes the cap, rotor and wires. Always inspect these parts and make sure they are in good conditon.
With that said wider is better to a point. And the wider you go the more energy it takes to jump the gap and if it is too far it might be blown out or be so weak that it does not get the burn going as well. We settled on 40 thousandths and have great luck but keep in mind we have one hot ignition system. I am afraid the 360's is not quite as impressive. I gapped mine at 30 thousands after the side gapping to start and I have an Iridium plug that requires less juice to make a good spark. You have to experiment but my experience tells me you could go to 35 or 40 thousandths and be just fine with the type of compression that we have. Especially with an Iridium plug. I will continue to experiment in my 155 foot time trial area and see the difference. I am down to 4.95 seconds and I started at 5.9 seconds stock. But also understand that you will have to maintainance your ignition system more often the wider you go. I read the recommendation on the side gapping of 10 thousandths less I think that is pretty conservative but also I do not think in our application there will be that much difference about 30 to 40 thousandths. Whew! That was long. Take care.

 

Yep the Dunlops are still on mine as well. But I have to tell you they are holding up pretty well for me. No flats yet and I have ridden hard. I rolled the poor 360 last weekend. It held up like a champ. I have been riding with a buddy that uses the Kenda bearclaws and they are a great tire as well. They ride smooth and have helacious bite and hold up very well. I however am leaning towards radials as they really do help the ride quality. My good friend has a Rincon 650 and he has radials from the factory, the tread is junk but man does it handle. Whatever you choose to do get the weights of the tires first and try to get the lightest because turning over heavy meats will reall zap the quad. Later