coils

[Raksj04]

I heard gen 2 coils were the most reliable coils mazda put in a rotary. Are they dead or are you trying to get smaller ones to clean up the engine bay?

[mattallac]

trying to clean the engine bay up ,the rx2 has very little room in the engine bay i found that the coils from the gen 2 has igniters on them i dont know this for fact if so that could be a factor . i am using a haltec sprint re ecu and bigger coils dont mean better spark .

[Raksj04]

Originally Posted by mattallac

trying to clean the engine bay up ,the rx2 has very little room in the engine bay i found that the coils from the gen 2 has igniters on them i dont know this for fact if so that could be a factor . i am using a haltec sprint re ecu and bigger coils dont mean better spark .

I have heard of a FB guy who did a super clean 13B-T swap. I think his coils were mounted under the dash. I didn't see the car but my friend james talks about it all the time. I think is AFM is after the turbo mounted behind the front fascia.

[RETed]

Originally Posted by mattallac

trying to clean the engine bay up ,the rx2 has very little room in the engine bay i found that the coils from the gen 2 has igniters on them i dont know this for fact if so that could be a factor .

Yes, the FC coils have an integrated ignitor built into the bases.

i am using a haltec sprint re ecu and bigger coils dont mean better spark .

Be careful with this statement...
It is true that the Haltech is able to adjust (i.e. lengthen) the dwell signal duration, but this fact should be kept independent of this discussion.
You can just lengthen the dwell duration and get a longer spark before you get to the point where you fry the coil, but this just means that you able to apply this fact to any coil you install in there.

If we isolate the coil by themselves, my statement still stands: physically larger coils will, in general, fire a better spark.
The coil is just a (step-up, DCV) transformer.
As long as it gets the minimum charge voltage and time, it will fire a spark that's dependent on circuit resistance and windings ratio...pretty simple.
Coils are typically rated by primary resistance, secondary resistance, coil ratio, current (and sometimes "work" - i.e. Joules), and max output voltage.

The easy answer would be to use some kinda CDI box for your coils, and just run the smallest coils you can find.
The CDI system negates most of the limitations from input charge time and minimum voltage.
Adding a CDI box just adds complexity and eats up space though...

One downside to running a smaller coil is that heat can sometimes become a problem.
If this is a race-only vehicle, then you just need the coil to stay cool for the duration of the race.
If you're going to street this vehicle, you gotta watch out, as most of the "race-only" coils are not made to run for long periods and can fry from overheating.

With all of that crap said, check out the MSD Blaster SS coil...
http://www.msdignition.com/Products/...r_SS_Coil.aspx


-Ted

[mattallac]

still dont agree bigger is not hotter spark/better spark ,with the epoxy / oil filled coils all the advantage can be is cooling.all coils are not the same , resistance ,saturation time etc.oil filled is old hat for coils and epoxy filled are compact and stay cooler .most of the cars made in the last 20 years that came with crank fire systems stock have enough mv to cook a man from the inside out,they are not large coils.they are coil over packs (small).i would like to know what the output voltages are on those huge coils that came from the 2nd jen(made in the 80's) and are they oil or epoxy filled,my bet is i can find smaller coils with the same if not more output voltage and less saturation time .