Over the years now sadly we have seen many people lose money and have numerous problems with either trying different coils to save money or to try and find some sort of performance advantage over the later Mazda coils .
Not only have we found the last two incarnations of Mazda coil to be very very reliable, but we know now though our Race car 100% that Genuine Mazda coils are more than man enough to help the engine produce 430 BHP !
Through mapping the car with Mazda coils we tried altering the dwell angle again and again and always came back to the Mazda setting.
My mapper actually thought that because RX-7 owners often upgrade to expensive AEM ignition that this may find us an advantage over the Mazda coil----------guess what----------damn waste of money that proved to be and we saw no gain what-so ever in any way through the map :oops: !!
On top of this I have had traders we deal with tell us that on most R3 models they have come across unless genuine Mazda coils are fitted, even with a re-map they won't run properly.
Bottom line is that through the Race car we have found that on a RX-8 engine you need never look any further than Genuine Mazda coils
Yes earlier 100 and 100A Mazda coils were bad, I even changed one set at 5000 miles for a customer
I can tell you that over the last six years we have sold literally thousands of Mazda coils not only to people on here and trade customers but also Mazda dealers throughout Europe and even out as far as Australia.
With all these sold we have never ever ever seen any 100C coils come back and with the 100B's we have had a hand full, however when we tested the coils secondary voltage we found no problem, so effectively over the last six years with these latest "modified" versions we have not had a conclusive failure.
It would be foolhardy to suggest these or any other coil for any car will last for ever, but all I can say is, had I not had full faith in the operation and durability of these later coils I would never have put them near our Race car even just to fire it up initially. http://www.racingbeateurope.com/mazda-rx-8-genuine-ignition-coils--spark-plugs-leads-etc-311-c.asp