View Poll Results: When do you change your spark plugs?
0-5,000 miles (I have money to burn)
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17
17.00%
5,001-10,000 (Just in case)
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44
44.00%
10,001-15,000 (The Haynes Manual knows all)
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32
32.00%
15,001 and up (I'm confused about the leading/trailing thing)
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7
7.00%
Voters: 100. You may not vote on this poll
Poll: Spark Plug Change...How often?
#26
After this thread was sprung up, the next day I went to the dealership and replaced my Spark Plugs. I had 10,049km's on them. Man were they black. Although I am convinced that was partly due to the stock OMP. I have converted to pre mix a short while back.
I will pull out my Plugs, In say 3000km's and give them a looksy. I'm sure to see them far less fouled than the previous ones. Also, I do notice a better response when I floor It on the high way ever since the Spark Plug change.
10,000 k's, far to long of a wait.
I will pull out my Plugs, In say 3000km's and give them a looksy. I'm sure to see them far less fouled than the previous ones. Also, I do notice a better response when I floor It on the high way ever since the Spark Plug change.
10,000 k's, far to long of a wait.
#28
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Originally posted by seventhgear
every 6 months i replace my plugs with ngk which arent expensive .. $10 for all 4 !
every 6 months i replace my plugs with ngk which arent expensive .. $10 for all 4 !
![eek](https://www.rx7club.com/images/smilies/eek.gif)
I've replaced mine twice with NGK's, and both times I paid CA$90 for all 4. Are we just getting royally screwed here in Canada or what?
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#30
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First time I got the service done at a Mazda Dealership, second time at a Midas. The price wasn't including labour, just the plugs! Boy, have I been getting screwed!
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#31
Starionx///You my friend got ripped off! For what Its worth, buy the plugs yourself than replace them yourself!!!
Really, If you put me on the clock, I will take them off, put anti-seize compound on the new ones, Install them with the wires In less then 10 minutes. Just do It yourself.
Really, If you put me on the clock, I will take them off, put anti-seize compound on the new ones, Install them with the wires In less then 10 minutes. Just do It yourself.
#32
I'm a boost creep...
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Originally posted by Turbonut
They eat plugs.Let's not forget that for every revolution the leading plugs fire 6 times, trailing 3. Compare that to a piston engine 1 revolution 1 fire. You can see why the plugs don't last.
They eat plugs.Let's not forget that for every revolution the leading plugs fire 6 times, trailing 3. Compare that to a piston engine 1 revolution 1 fire. You can see why the plugs don't last.
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A single piston has one power stroke (i.e. plug fires) every two revolutions. A single rotor has one power stroke every one revolution. So a 2-rotor 13B has the same number of power strokes per revolution as a 4-cylinder, but only half as many as a V8. You’ve gotten your rotor and eccentric shaft speeds mixed up. Each rotor makes one revolution for every three revolutions of the eccentric shaft, not the other way around.
You’re right that the leading plugs fire twice as often as the trailing plugs, because of the wasted spark system used for the leading plugs. (Sean, you should know that!
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The reason rotary plugs don’t last very long is not because of how often they’re fired, but because of the temps they experience. In a piston engine the plug is heated up to combustion temp then cooled during the intake stroke. In a rotary the intake takes place in one part of the engine, combustion in another, so the plugs remain at combustion temp all of the time. Despite the fact they are engineered to withstand much higher temps than regular plugs (hence their higher cost), they still don’t last nearly as long.
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#33
I'm a boost creep...
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Originally posted by silverrotor
If you put me on the clock, I will take them off, put anti-seize compound on the new ones, Install them with the wires In less then 10 minutes.
If you put me on the clock, I will take them off, put anti-seize compound on the new ones, Install them with the wires In less then 10 minutes.
![Wink](https://www.rx7club.com/images/smilies/wink.gif)
#34
My TII is idling and running perfectly. It's also getting pretty good gas mileage (for a TII). It's all stock except the exhaust and some suspension goodies. The plugs have been in there for 2 years (15,000 miles or so) and I have never had a problem. I use the stock NGKs and pay about $3.00 each for them at Advance Auto Parts.
Todd
Todd
#36
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Originally posted by akageals
My TII is idling and running perfectly. It's also getting pretty good gas mileage (for a TII). It's all stock except the exhaust and some suspension goodies. The plugs have been in there for 2 years (15,000 miles or so) and I have never had a problem. I use the stock NGKs and pay about $3.00 each for them at Advance Auto Parts.
My TII is idling and running perfectly. It's also getting pretty good gas mileage (for a TII). It's all stock except the exhaust and some suspension goodies. The plugs have been in there for 2 years (15,000 miles or so) and I have never had a problem. I use the stock NGKs and pay about $3.00 each for them at Advance Auto Parts.
Oh yeah, to whom it may concern, I got lazy and didn't change my plugs. My dad beat me by a second in his 'vette.
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#37
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Originally posted by silverrotor
Starionx///You my friend got ripped off! For what Its worth, buy the plugs yourself than replace them yourself!!!
Starionx///You my friend got ripped off! For what Its worth, buy the plugs yourself than replace them yourself!!!
I went to Canadian Tire, and they don't sell them!
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#39
Seduced by the DARK SIDE
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Originally posted by akageals
My TII is idling and running perfectly. The plugs have been in there for 2 years (15,000 miles or so) and I have never had a problem.
My TII is idling and running perfectly. The plugs have been in there for 2 years (15,000 miles or so) and I have never had a problem.
I was eating steel leading plugs in 10K, so I upgraded to platinum. I cleaned & checked them at 20K, and they still look good.
#40
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Anyone have a good website for some NGK's ? Or do most of you guys just buy plugs locally? New owner of a TII and i dont even wanna know when the last time the kid changed the plugs on that thing was. Someone help me out with a place to buy em at a decent price?
#42
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Originally posted by NZConvertible
Each rotor makes one revolution for every three revolutions of the eccentric shaft, not the other way around.
Each rotor makes one revolution for every three revolutions of the eccentric shaft, not the other way around.
Crank speed and Rotor speed are not the same. I used to think so too until I read a lengthy article on the ignition system. If you look at how the motor is put together it all makes sense.
#43
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lol im glad I read this post, i bought my rex with 88,000 miles on it and now it just reached 100,450 and i havent changed the plugs yet
eeck but i will wednesday so what do you guys recomend, my local tire store that i go to or the mazda dealership, Or if i should just get the plugs at a place like Advance auto parts or carquest? and if i go that route, will using my haynes manual make it so it will be an easy install? thanks guys and i eagerly await your response
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#47
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In dealing with normal mechanics is there much if any difference in instaling spark plugs compared to Pistons, like room for error, or just a no-how of how the rotary's work and what not, I.e. are they basically the same all across the board piston/rotary?
#49
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I would change my plugs more often, but my trailing plug holes are stripped and I can't remove them ![Frown](https://www.rx7club.com/images/smilies/frown.gif)
Any suggestions on how to get them out?
Keep in mind this is my daily driver, so no creative engineering.
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Any suggestions on how to get them out?
Keep in mind this is my daily driver, so no creative engineering.
#50
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Heli coil, if they make them that big & in metric. You'd have to worry about getting shreds of metal in the chamber too. I'd say your proper fucked.
Excuse the french.
Excuse the french.