Alternative performance direct fit coils?

[sztriki]

The D585 coils used by BHR can theoretically benefit from extending the ignition dwell by a remap of the PCM.

IME it makes no noticeable difference and needs to be reversed if switching back to oem or RRP MkII or MkIII versions.

Sent from my SM-G800F using Tapatalk

[R1DSO]

My 2 cents on this topic having changed my coils and leads earlier in the week...

I had waited a couple of months or so for the RRP versions, but, with the pandemic, there were big delays with getting parts. After a a slight miscommunication, it sounded like the coils were still some way off when I cancelled my order, which ironically ended up being the day the mkIIIs came in to RRP . Carl kindly gave me an instant refund.

I ended up buying a set of genuine Mazda revision C coils and Magnecor leads. I could find no evidence in the service history that came with my car that in 55k miles, the coils had ever been changed. However, when I took them off, I was surprised to see they were revision B coils. I was under the impression that all R3s came with revision C’s :

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As suspected, my old coils had failed with prominent white spots on 3 out of 4 of them:

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I whipped off my spark plugs to check their condition. The dealership I bought the car from had fitted new NGK Iridium plugs before I collected the car in March. I think they must have put them on with an air wrench as I had to use a breaker bar to get them off . So much for adhering to the delicate 17nm torque spec in the service manual.

In the 500-600 miles of driving whilst I was waiting for new coils, the plugs had become a bit fouled. This is what the worst one looked like, although I understand it’s better to let RX-8 plugs ‘self-clean’ rather than tamper with them:

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The difference the new coils/leads have made is night and day. The car now starts up instantly and pulls strongly and smoothly from much lower revs. Before, there was hesitation around 4k and a real lack of torque low down, resulting in jerky set-offs at low revs. The car is really responsive and zingy now. Induction noise seems to be up also (in a good way), presumably from stronger fuel ignition.

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I know revision C coils are used on race cars with 300+ hp, so provide enough power and durability for fast road and track use. I’m assuming that they’ll have a 25k mile lifespan, but not sure on if their performance degradation is linear and how this compares to the RRP coils. i.e. do coils get progressively weaker over their circa 25k lifespan, or do they suddenly ‘fail’ .

[R1DSO]

There's no evidence to suggest that genuine (rather than fake) Mazda Rev C coils have a 25k or any other lifespan limitation.

The use of quality HT leads makes the biggest difference to the life of the coils; the OEM ones were pants.

[Ainmhidh]

I've no idea what spec the original (I assume) coils were on my R3 before I swapped them at 28k - I probably still have the box with the old parts so I will check if I can lay my hands on them.

[New Duke]

I ended up buying a set of genuine Mazda revision C coils and Magnecor leads. I could find no evidence in the service history that came with my car that in 55k miles, the coils had ever been changed. However, when I took them off, I was surprised to see they were revision B coils. I was under the impression that all R3s came with revision C’s :

I know revision C coils are used on race cars with 300+ hp, so provide enough power and durability for fast road and track use. I’m assuming that they’ll have a 25k mile lifespan, but not sure on if their performance degradation is linear and how this compares to the RRP coils. i.e. do coils get progressively weaker over their circa 25k lifespan, or do they suddenly ‘fail’ .

There's no evidence to suggest that genuine (rather than fake) Mazda Rev C coils have a 25k or any other lifespan limitation.

The use of quality HT leads makes the biggest difference to the life of the coils; the OEM ones were pants.

When my car had it's first service under my ownership in 2017 at 48k miles the factory Rev B coils were still on the car (yes R3s were fitted with Rev B). So replaced them with new Rev Cs and Magnecor leads.

20k miles and exactly 2 years later when Boston Rotary replaced the Rev Cs with RRP coils and new leads, one of the Rev Cs had already started to fail.

Taught me 2 things:

- When you buy a used car that you cherish service or replace everything.
- Check the condition of the coils every year.

[R1DSO]

When my car had it's first service under my ownership in 2017 at 48k miles the factory Rev B coils were still on the car (yes R3s were fitted with Rev B). So replaced them with new Rev Cs and Magnecor leads.

20k miles and exactly 2 years later when Boston Rotary replaced the Rev Cs with RRP coils and new leads, one of the Rev Cs had already started to fail.

Taught me 2 things:

- When you buy a used car that you cherish service or replace everything.
- Check the condition of the coils every year.

Wow. 20k miles isn’t much, although that will probably take me a few years to do with the light usage my RX-8 will get. However, I’ll take on board the tip to check the base of my coils on an annual basis as a precautionary measure.

Out of interest, can you check the condition of the RRP coils without electrical testing equipment? I’m aware that they have a heat sink in place of the OEM base that goes white when failing.

[R1DSO]

Get a set of these and check for a strong spark
https://www.ebay.co.uk/itm/AccuSpark-Sp ... 1934972625
much more diagnostic than "goes white when failing"

[R1DSO]

Get a set of these and check for a strong spark
https://www.ebay.co.uk/itm/AccuSpark-Sp ... 1934972625
much more diagnostic than "goes white when failing"

Thanks Dave . Never seen those before! Now added to my shopping list .

[ChrisHolmes]

Just for clarity, the new BHR coils (and the RRP ones) are not D585 based. I don't know which coils you were talking about, but just putting it out there that the later coils from both companies are not based on D585s

[MadTaz]

Just for clarity, the new BHR coils (and the RRP ones) are not D585 based. I don't know which coils you were talking about, but just putting it out there that the later coils from both companies are not based on D585s

I can say the RRP ones are IGN based now matched with an OEM style igniter (MKIII).

[MadTaz]

That might have been me

a V8 spinning at 9000 RPM fires as often as a rotary at 4500rpm, most neglect this fact. a rotary fires every revolution, a 2t fires every revolution, an 4T fires every second revolution.

at 9000rpm each revolution takes 6.67ms, a Spark takes 2 to 3ms to fire/discharge. this leaves onl 4 to 5ms for a coil to charge.
Sound good, no it doesn't. a 5s charge (required by d585) to get energy close to the oem coils pushes is not available. as previous charge has not yet completed. at most it is available 4.5ms/6.67ms=67% duty cycle. it will kill most of the coils for anything longer than less than 10 second!

Dont forget, they were designed for a max 9000Rpm on 4t, ie 5ms dwell at 13.3ms(cycle) ie 37% duty.... most coils cant handle anything above 40% for longer period of time!!!!

The only coils that were designed for high rpm are the Mercury marine 2t coils (ign1a, pantera, holey, sakebomb etc), and coils on a 4T RR bikes (didnt really see any reving 18000 rpm with near plug smart coils ! )


I have fallen in to the same stupidity and purchased the d585 uninformed and misguided by all the YouTube experts (paid advertisement) which I trusted without thinking my self...

Its really easy to se how d585 got popular by just a few of them being given for free plus some sponsorship money to the few....than everyone wanted to copy and "gain" some profit and start selling them selfes

RRP did an informative post on Duty Cycle: viewtopic.php?f=205&t=79271

I think you might need to be a member to see it though?

[350matt]

the RRP coils are designed for the engine and are still on mine still working well 2 years and 35K miles on....
or just fit mazda C's

[Milos_Balunovic]

Just for clarity, the new BHR coils (and the RRP ones) are not D585 based. I don't know which coils you were talking about, but just putting it out there that the later coils from both companies are not based on D585s

BHR Long lost any credibility with me and their pushing of the d585 coils. these look more like just adapted housings on a d580 of 585 (in similar fashion as RRP has developed based on ign1a).....
Their (BHR) last sentence on the description is just pissing on their previous top recommendation that they pushed so willingly.. there it ends with me. their name no longer gives any value to provided items.

Also They mention its 9k+ engine (a 4t again).... 80% duty cycle is IMPOSIBLE on a rotary at 9000rpm, total cycle (1 rotation) lasts 6.67ms, spark in minimal with inducting coils lasts 2ms. that leaves at best 4.67ms for dwell that is 70% (theoretical max..) let alone the talks "more than 80%


Even thought I have been on this forum so much and read most of the staff, most of the items written on the topic of coils is so wrong and misunderstood (again I was in a same position, but I was able to educate my self at least to recognize and call BS when I see it)

Im not here to push any products, I still cant decide what to replace my now failed d585 coils after less than 15000km...

Now im split between Ign1A where energy measurements at oem dwell tables are low (1.85ms) at 9000rpm (so you can see the bulshit that BHR-s can take 5ms.... and here is the oem 14V "dwell" table
RPM-1000-2000-3000-4000-5000-6000-7000-8000-9000
DWELL-4.42-3.58-3.14-2.85-2.65-2.38-2.04-1.78-1.58
or the RRP which are a copy... and I dont know who to trust

[Milos_Balunovic]

That might have been me
.........f them being given for free plus some sponsorship money to the few....than everyone wanted to copy and "gain" some profit and start selling them selfes

RRP did an informative post on Duty Cycle: viewtopic.php?f=205&t=79271

I think you might need to be a member to see it though?

yes cant see it

[MadTaz]

or the RRP which are a copy... and I dont know who to trust

A copy of what??

[Milos_Balunovic]

or the RRP which are a copy... and I dont know who to trust

A copy of what??

Sorry abrain fart .. ment to be "inspired by" ign1a

[MadTaz]

or the RRP which are a copy... and I dont know who to trust

A copy of what??

Sorry abrain fart .. ment to be "inspired by" ign1a

Certainly some technology that differ the two, i.e. put Marine IGN 1A coils on an JDM Rx8 and itll illuminate the check engine light, not so with RRP.

What's stopping you from just reverting back to OEM C revision coils.

[SprintRX8]

I’m got the AEM coils on a recommendation from a Turbo RX7 owner.
He went thru various aftermarket ones and recommended the AEM.

Also don’t overlook Spark plugs.
No point upgrading the coils if your using non genuine Spark Plugs.

[MadTaz]

I’m got the AEM coils on a recommendation from a Turbo RX7 owner.
He went thru various aftermarket ones and recommended the AEM.

Also don’t overlook Spark plugs.
No point upgrading the coils if your using non genuine Spark Plugs.

And also Ignition Leads, this has led to us producing the RRP lead, 95% the quality of MSD, c50% of the price to encourage all those whom replace coils replace the leads too.

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[Milos_Balunovic]

I plan to upate evrything as a package.

re 585 failing, I noticed first that rev limiter sounded more like ignition braking apart than actual rev limit, in few km it went down to 7k rpm, and when I went to start the car to move it before I change sparks to br8/9es (and gap them to 0.8mm untill I decide/order what I want/need) the car started single rotor....

so the d585 don't have the energy anymore needed to fire the oem sparks at 1.15mm gap.

The plan is absolutely to get MSD leads (whatever coils I chose) and new oem sparks

[Jester*]

The RRP products are all developed for quality at a good price, which is definitely something I can get behind.

I certainly have no problems recommending them. The Mk3 coils have been fitted and had 0 issues with them.

[warpc0il]

The NGK rotary plugs aren't designed to be "gapped" and it's not uncommon for the earth electrode to break away if stressed.

I'm convinced that the poor quality of the OEM ht leads, particularly the plug connectors, is a major factor in the premature coil failures.

The connectors corrode creating high resistance to the centre electrode while leaving a conductive residue on the insulator.

It's not unusual for the top of the plugs to rot away.

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[bigpete8]

It's not unusual for the top of the plugs to rot away.

Mine had on trailing side before I changed plugs, coils and leads.

[Milos_Balunovic]

The NGK rotary plugs aren't designed to be "gapped" and it's not uncommon for the earth electrode to break away if stressed.
...

None are designed, but I still use "gapping" as a way to measure how worn they are. measure the gap when new, and check if within specs (1.15 new, 1.25 old / to be replaced) if they are out of spec when received, I don't use them. if they are than I use it to follow the wear rate on them

Also most are not capable of gaping a BR6S plug, let alone an EIX (where most break of the center electrode) or specials like the ones on our engines with proper care it can be done.

[RenesisRaceBuggy]

Yeah the stock leads are shocking, I don't think we ever got even a full day of racing out of them before they started to break down, never mind the water ingress issues.