Spark plugs seal
- Thread starter Boss302
- Start date
Boss302 said:
I doesn't HAVE to.. But it will be better off to get that gasket because If junk gets in there and you pull your plugs it is a chance of garbage getting into the cylinder.. Most times on our cars if you haven't replaced the cam tower seals they will start leaking in there..
A new #3 gasket is about $35 from toyota. The spark plug boots on most after market sets don't seem to lock in at the gasket, which leaves a little gap for water to get into the hole. That's why most folks don't pressure wash the engine.
to make sure we're all on the same page, forgive me for not explaining better, where the spark plug boots go into the wholes when you put stock wires in there they "seat" thus keeping contaminates from getting in there this is understandable but is it absolutely neccessary to seal it off iff i were to keep things clean?
If you were to meticulously maintain that center galley, no. It's not absolutely necessary to have that cover. It is, however a very, VERY good idea to keep it on.
Suprasport.com has some nice aluminum ones...
Suprasport.com has some nice aluminum ones...
what i'm trying to do is put 10.5 or 10.8 wires down in there and i'm trying to figure out how to "seat" the boots i could bore out the old boots and use them but thats one option i wanna se if i have more.
10.5mm or 10.8mm ignition wire?
it should fit under the coil pack with the 3rd valve cover on (that is its official name btw)
it should fit under the coil pack with the 3rd valve cover on (that is its official name btw)
drag wires for what? you running a magneto or something?
at 8mm it is plenty. Anything else gets you nothing. Not even a fatter spark.
at 8mm it is plenty. Anything else gets you nothing. Not even a fatter spark.
Just go with the MSD's.. $80-$100. Unless you already have the larger ones. You can always use silicone around the edges to help seal plug wires..
with a thicker cored wire there is less ohms per foot correct? less resistance mens better spark correct? i'll admit it i'm still learning but with electricity i know that if it can find a easier route then it WILL take it. a thicker core is a easier way correct? if i'm wrong please by all means correct me if not you somebody.
Boss302 said:
big negative
that is true for low voltage but when dealing with high voltage as seen in the igntion, resistance really does not mean anything (if you really want proof replace ignition wire with a person and still see the sparks fly). High voltage tends to acts as a magnetic field in which is travels through the skin of the wire. Ironically they call it skin effect.
Skin effect applies only to A/C signals and is typically negligible until you get to a few GHz. The skin effect is the tendency of an A/C signal to concentrate its current density near the surface of the conductor... the "skin" of the conductor. It is really a manifestation of self inductance.
To compute the skin depth, use d = sqrt(2*p/(w*u)) where w is the frequency (in radians), p is the resistivity, and u is the permeability.
Due to the relatively slow rise and fall times of an ignition pulse, the skin effect will not be important.
To compute the skin depth, use d = sqrt(2*p/(w*u)) where w is the frequency (in radians), p is the resistivity, and u is the permeability.
Due to the relatively slow rise and fall times of an ignition pulse, the skin effect will not be important.
Well, skin effect is an attribute of high frequency AC current, usually associated with RF. Not accurate as it applies to spark ignition.
Here's one for you. The plug pairs in a DLI system like the turbo Supra are in series right? Did you know if you put each plug from a pair in two different engines with no connection between the engines both plugs would still fire? 'Splain that one and I'll be impressed
edit: 3p beat me. Good show
Here's one for you. The plug pairs in a DLI system like the turbo Supra are in series right? Did you know if you put each plug from a pair in two different engines with no connection between the engines both plugs would still fire? 'Splain that one and I'll be impressed
edit: 3p beat me. Good show
? re-word please
jetjock said:Here's one for you. The plug pairs in a DLI system like the turbo Supra are in series right? Did you know if you put each plug from a pair in two different engines with no connection between the engines both plugs would still fire? 'Splain that one and I'll be impressed
so then running a thicker wire is not a problem then ay? i know the 8.5 is good but i want the best and the Taylor 10.5 or Accel 10.8 seem to be the optoin. so yet again is my train of thought good or bad haven't really figured it out yet.
3p
lots of unknown in that equation
Lets get the finished product using the known typical carbon that 95% of all wires use. Also make sure to use stranded as we don't use solid conductors in our cars
lots of unknown in that equation
Lets get the finished product using the known typical carbon that 95% of all wires use. Also make sure to use stranded as we don't use solid conductors in our cars
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Okay, carbon has a resistivity of 1375 uohm-cm and permeability of 1. Assume 1us rise time then that gives a skin depth of 186 microns. For stranded wire (that is insulated between strands) then the skin depth likely exceeds the strand diameter, in other words it doesn't matter. For solid core or uninsulated multistrand a center conductor larger than ~0.4 mm is pointless (assuming you can actually achieve a 1us rise time).
Boss302 said:
The 7MGTE uses a distributorless ignition system often called DIS but more correctly called DLI. The plugs are fired together in pairs, once on the compression stroke and again on the exhaust stroke. The firings on the compression stroke are called true firings, while the ones on the exhaust stroke are called waste firings, hence the name "waste spark" used for such systems. Not only do the plugs fire twice as often as usual but they also fire with opposite polarities. I won't bore you with the plasma physics involved but this is one reason platinum or iridium tipped plug electrodes are used.
Anyway, the plug pairs are connected to either end of the same coil pack secondary winding. A common belief is they're then connected together by the cylinder head which completes the circuit and provides a path to ground. This isn't true and is why you can put a plug and it's companion in two different engines and each plug would still fire even though only one ignition system is involved and there is no connection between the two engines other than the two plug wires and coil pack.
Another way to look at it is if one plug circuit becomes open it's companion will still fire whether it's mounted in the same head or not. Since the plugs are in series with each other and the secondary coil winding the question posed was how any of this can happen. There's an explanation of course but I'm not just going to cough it up
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