Spark Plugs and Ignition

I was wondering about those step-colder plugs too. I'm getting ready to start doing some engine mods on my car and I guess after hearing everyone's feedback here, I will eventually be purchasing the Denso ITV 24's.

Also, not to steal this thread, but while we're on the topic of ignition, has anyone used the HKS Twin Power DLI Ignition Amplifier listed on the protege garage and street unit websites? It has a fairly lengthy description, and for $500 it must do SOMETHING worthwhile, but I can't fully grasp what it does. Would this be something good to pair up with step-colder plugs and is it worth $500, or is it completely unrelated and overpriced?

From the protege garage website:
The Twin Power ignition amplifier incorporates both the CDI and transistor method ignition to provide optimum spark duration and maximum voltage output, resulting in crisper throttle response and a smoother engine powerband. The CDI method, capacity discharge ignition, provides maximum voltage by transferring all stored energy in the capacitor to the ignition coil so that the ignition current can buildup quickly, thus making the Twin Power very effective in the higher revs where a normal spark would tend to diminish. This strong rapid spark prevents the high rpm ignition miss that reduces peak power. The transistorized method generates high voltage by using transistors to cut off current to the coil, thus allowing for a long energy discharge. This longer spark duration allows the Twin Power to improve lower RPM throttle response and torque. The combination of the CDI and the transistor method incorporates two distinct systems into one high performance unit, hence the designation of Twin Power. The Twin Power produces a spark output that is typically 1.5-2.5 stronger than of the stock ignition system and consumes about 35% less power input than other ignition amplifiers. Each compact and attractive Twin power unit is constructed of durable anodized aluminum and sealed to prevent corrosion from moisture.
 
Or you could just wait another couple of months or so and we'll have upgraded coils for our cars at half the price of the HKS amplifier...
 
Or you could just wait another couple of months or so and we'll have upgraded coils for our cars at half the price of the HKS amplifier...

Really? Who will be building them? If that's the case, I can wait...I am in no particular rush. I may just start with the Denso ITV24 plugs for now and then wait until some better coils come out.
 
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Or you could just wait another couple of months or so and we'll have upgraded coils for our cars at half the price of the HKS amplifier...
I hate when you do this to us Auto X. I of course want coil packs too! make sure they are ready for New York springtime. I had some random misfire cels before i put the car up. The dealership said the plugs looked bad [stock plug stock gap] but they said they would need to start with plug replacement and work their way back. I said i would replace plugs myself as i still had the colder ones. So i tried those and no more cel, but it was not right. so tried to tighten up the gap and broke a 'trode. 3 colder 1 stocker regapped to 30. Ran it about a week before putting the car into cold storage. I feel com spring I will still not be right and will have let Mazda do the trouble shooting. But i wondered if i have multiple coil packs going bad on me. I thought i remembered others mentioning it as a warranty repair. Hope i am not going too far off topic. But i really am interested in quality spark to be sure to keep up with all the bolt ons i have and lots of others do to.
 
I love when new stuff comes out! I had been looking at the HKS Ignition Amplifier and wondering the same thing, people say the car feels smoother and stronger with it installed. Do the upgraded coils basically achieve the same goal of a better spark, but by a different method than amplifying the signal?

Edit to specify the ignition amp, not the HKS plugs, sorry.
 
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coming from a automotive tech, go ahead and skip the hassle pick up the Denso's. I think someone said something about these plugs not wanting to be gaped that they have a chance of breaking and this is true.
 
Just curious, when you install the new plugs you don't have to do anything fancy right? Is there a torque spec I need to know or is it just screw them on. I know maybe a dumb question for some but Ive never change out the plugs before. Thanks
 
Good question. The torque is very importatnt because you are tightening against aluminum, which is kind of soft as far as metals go. If you were to over tighten you might well strip the threads and that would be no fun at all. I bet someone already knows this spec but i will look it up again if need be. And I am sure Mazda will tell you if you ask service. I also use a little bit of high temp anti seize. But that part may not be recommended practice. I tend to look at the condition of my plugs alot though. I am sure you will get more good input from the folks here!
 
Torque specs for the spark plugs are: 10-14 N.m (8.0-10 ft.lbf)
Definitely apply anti-seize on the threads of the spark plug.

Make sure the gap is between 0.7-0.8 mm (0.028 - 0.031 in)

There is also a defouling technique called a "no-load racing" to clean the spark plugs: race engine to 4,000 RPM and hold for 2 minutes until RPMs return to idle on its own; then release pedal. Repeat again; for a total of 2 times.

I hope this helps.
 
does anyone know the stock number for the ITV-24? denso's website does not list that plug for our car and i am seriously intrested in these! lmk!
 
does anyone know the stock number for the ITV-24? denso's website does not list that plug for our car and i am seriously intrested in these! lmk!
i will be looking into these plugs also come spring time. I think SU carries them.
 
This is a good post guys. I am getting more trigger happy on purchasing the denso's. I'm relatively stock, COBB intake. I will do anything to prevent possible knock and its something that concerns me. What you think good idea or waste of my money?

Thanks autoX great info you d' man!

EDIT: I looked up part numbers and I suppose the Denso OEM replacement is ITV20, which are .044'' gap. The one step colder is ITV22 but that's a .030 - .032'' gap. How did you find out they are within spec? JW Thx.
 
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