I typically don't factor in the possibility of changing your own dwell when i make coil recommendations, because owners that are asking about what coils to use most likely don't have any flash based tuning in hand. Most DIY coil threads I've seen HAVE had some sort of issue that has to be solved, typically a dwell adjustment though not always, and the people that haven't been able to make that change end up going back to OE coils. For the average owner with a stock 8, the cost of a DIY kit ends up including the cost of a tuning method, which immediately makes the kit not plug and play. The BHR kit has the advantage that it IS plug and play. Even if I could put together a kit for your quoted price that worked right the first time, the plug and play value is still considerable just to avoid wasted time or mistakes due to ignorance, arogance, or butter fingers. This is true for most people.

For example with my MSM, when I had the choice of a plug and play $2,000 ECU with post-purchase support and tunes or a bare bones ECU that has to be manually wired and configured for $850 ... I picked the more expensive plug and play option, and haven't regretted it a bit. I get your same argument from the guys that picked the other option.


Back to coils....

When I went to educate myself on what dwell is and what factors are important, I can easily see the problems with incorrect dwell times. In a general way, they can be summarized as:
- Under dwelling the coils typically leads to misfires as the coils can't charge sufficiently before needing to release the charge
- Over-dwelling the coils will shorten their lifespan considerably as it builds heat that has to be held for longer than needed before releasing the charge.

So seeing a comment that suggests an raising of the dwell from a point that already functions well is something that makes me question what is really going on, and what kind of lifespan you can really expect.

 

Ok, you confused me a little. That coil setup worked for me for around 1000 miles before I raised the dwell. My pourpose for raising the Dwell was only with plans of going FI and wanting all the spark I can get.

 

I guess I'm pointing out that more isn't necessarily better.

More is better if you don't have enough, but if you have enough, more is just hurting your coils.

 

There are lots of ways to spend money on more fun. Original poster asked what the cheapest trusted replacement coils are, and I listed the cheap OEM replacements that can be found at auto parts stores. You listed the expensive BHR kit. He can take from those two answers what he wants, but the original question wasn't 'what is the best performing coil replacement, regardless of cost?'

And you just need to return the coils and say 'they are giving me intermittent misfires', easy as that. Auto parts stores don't ever give trouble.

 

I said it was his decision. I said he should get the coils he is happy with and can afford. I know what this thread is about. I think in the long run the BHR coils will be cheaper with lifetime use and better mpg each gallon of costly premium gas. As I and others on this thread have echoed, In the short run, getting the cheaper coils looks smart. but in the long run and in the hopefully long life of his RX8 getting cheaper coils with poorer mpg and repeated warranty replacement uncertainty and the risk of a failed coil leading to cat or engine damage, he would be better off financially with the BHR kit. But hey the op had really already made up his mind by middle of this thread . After that it looks like he was just wanting some validation for his choice. LOL

 

Yes I ended up buying the intermotor coils for very cheap since I definitely do not have $500 to throw down on coils, at least not until well after the school year is over. Now I'm just trying to see what I might get the next time. It looks like if the $500 is kicking around the bhrs might be the better all around buy. I'll have to see how long these coils last me though. Can anyone say what kind of mpg numbers the bhrs might produce over the intermotors? And if possible convert it to canadian language but thats ok if not lol.

 

0, because there is no gaurantee that a simple ignition will increase power or mileage with any repeatable effect from one car to another. ambient condition changes are usually enough to skew results to invalidate them because they are so minor in comparison. all you have to work with is that most people notice very minor gains to their averages, the benefit is the slight gains and support you buy with them.

 

The power and mileage difference between two brand new coil types is negligible at best, below what dyno variances can detect.

The power and mileage difference between a set of failing coils and any brand new ones is significant: https://www.rx8club.com/series-i-tro...-plugs-234383/

 

That is the answer I was expecting. And I'm also expecting that the life of the coils varies quite a bit from driver to driver and from motor to motor. I've already installed my new coils on my car and since I don't know the brand or when my last coils were last replaced I'm going to see how long these last me before committing to getting bhrs next time. When my coils die and if I remember I will post how long they lasted and what I decide to do.

For now though and for anyone who just had the same question as I did going into this problem (which is the title of the thread) The intermotors from advanced auto are probably the way to go. But remember to order them in two separate orders to maximize your discounts from the promo codes!

 

I disagree here with RIWWP though I respect his vast knowledge on most things RX8. No I did not do a scientific test with exact same conditions with the new oem coils (with a properly broken in engine) and the new BHR coils. But I have been driving these rotaries for decades with almost every kind of coil setup for street and track rotaries. When I installed the BHR kit I immediately got a hp and performance bump over the oem coils when they were new, and immediately got better mileage ( one to two mpg better) than when the oem coils were new (on a properly broken in Renesis). People seem to want to say these cheaper coils and the BHR are equals when new. THEY ARE NOT. Drive an RX8 with the BHR coils and drive the same RX8 with oem or simliar coils and tell me they are equal. no way ! If it makes you feel better to get a bargain on coils, fine. I am not rich either and I like to save money like anyone, but if 40 yrs of rotary cars and mods and maintenance has taught me anything with these cars, you get the performance and the longevity that you pay for. Do the work yourself and save loads on labor while learning a lot, but if you want the best for the price, buy the best parts that work the best and never look back and regret the shortcuts you took.

 

one mans placebo is another man's scientific proof.

Posted From RX8Club.com Android App

 

No, actually, I didn't say this.

What i said is that the difference in quantified mileage and quantified power is negligible and below what can be measured on a dyno. A 2% variance on a dyno can be expected from run to run, and that is 4hp. Unless you can claim that there is a 4hp increase from new OEM/Whatever coils to new BHR coils, I stand by my statement. Even Ray agrees that while there may be a benefit, it isn't enough to measure.

Same with gas mileage. A 5% increase would be...1mpg? That hasn't even been reported that a BHR equipped 8 can get 1 more mpg than OEM equipped coil ones, so the gain must be lower.

I'm not saying that there isn't a gain, but any perceived gain for BHR coils has to take into account that the prior ignition was not performing properly to spec.

I don't disagree that they are the best ignition components possible, but I have yet to see proof that BHR coils have measurable power and measurable mileage gains over brand new OEM ignition. Every gain example I have seen brings the RX-8 up to what is easily reached by stock 8s with new ignition, suggesting that it is simple recovery of what was lost. I have yet to see a BHR ignition install result in numbers that exceed what stock 8s can get.

 

I have yet to see a BHR ignition install result in numbers that exceed what stock 8s can get. (quote from RIWWP)

Maybe you have yet to see this, but I have seen it and felt the difference and drive it every day, and I am NOT talking about compared to used coils, but compared to my oem new coils. This is a new member thread and many naysayers here have never even driven the same RX8 with new oem coils, then new BHR coils. Have you done that RIWWP, the same RX8 with new oem coils, then new BHR coils ?

In 4 decades of rotary ownership (spending more than a large six figure amount on mods and maintenance of seven rotaries) I know quantitatively when I am getting better hp and mpg, even a slight increase. I am getting that with the BHR coils and wires. If you choose not to believe that, that's fine. I will continue to enjoy the extra smiles and miles.

BTW RIWWP I look forward to seeing you and your MX5 at NJMP in April where we can continue this discussion in person.

 

# of miles + # of rotaries owned + # of money spent != tuned butt dyno



To assume none of us have played with other forms of ignition is hogwash.

 

gwilliams, so far you have given me exactly what most provide: A statement that you obtained a gain. What is the quantitative measurement to back that up? Got a dyno comparison? A record of mileage differences? A dyno will be hard to obtain, but mileage would be easier. Keep in mind that I, and others, could get 24mpg or more on stock ignition. How much can you exceed that with BHR?

I'm open to being wrong, but so far, I have never seen evidence that I am. Only that people with failing ignition replaced it.

Posted From RX8Club.com Android App

 

And to segway back to the original topic - it's pretty clear that the BHR coils do not give a significant boost in power over a properly functioning OEM coil. So go ahead and get the Advance Autoparts or O'Reilly OEM coils for <$100 for all four, and replace them under warranty every 20-30k miles for maximum performance. Or spend a lot more on the BHR coils and don't worry about replacing them - less work for you, but (a lot) more money.

 

I wouldn't say that its "clear" moreso than I would say that there hasn't been any actual qualitative testing done to prove that or dismiss that

 

Are you suggesting that a properly calibrated butt-o-meter is not quantitative proof?

 

 

That is my definition of clear. Put another way - there is absolutely no evidence that the $500 coil kit from BHR is going to give you anything other than maintenance-free longevity. To some, that may be worth $500. To me, I'll spend $96 on OEM coils and replace them free under warranty every 30k miles (or 2 years).

 

If it makes people feel better if they naysay against the BHR coils, then hey believe what you wish everyone. It is no sweat off my brow if you never buy BHR coils and keep rebuying or replacing oem coils forever.

For me, I have driven with NEW OEM coils (on a properly broken-in Renesis,) and then NEW BHR coils (on the same properly broken-in Renesis) under as similar conditions as possible, and there is a very noticeable difference. The OEM coils do not match the hotter, higher voltage spark delivered by the BHR coils . This contributes to better and more complete combustion. Ask BHR's Charles (though he might not want to alienate any potential future customers). He would honestly tell you he didn't put together his coils to JUST give longevity. He set out to put together coils and wires that give greater performance than stock oem coils whether you remain NA or go FI. And yes the mileage has also improved slightly and NOT compared to worn coils, but compared to new oem coils.

Folks here will never agree on this, that is fine. I will keep using the BHR and take my better performance and mileage to the bank, thank you. For others just enjoy your stock oem coils and be happy. The best to you all.

 

We aren't "nay saying" the BHR coils. They are indeed great coils. We are saying that there hasn't been a single owner that has produced quantitative test results proving any point of mileage or power.

Even Ray refuses to make a statement of gain for power or mileage.


If you want to be the first to produce the test results to back it up, plenty of us will be more than happy to accept it. But without test results, we aren't giving the BHR ignition any more credit than BHR is.

 

Hey just keeo non believing, thats fine. I know these cars and their performance and I have tried just about every mod and addition since rotaries came out in the early seventies. I know what I see and feel in performance and mileage. And BHR is no different from most reputable suppliers, they aren't going to risk liability in case someone doesn't get any claimed hp or mpg bump. But that doesn't mean the reality isn't so. Of course many nonreputable suppliers will claim all kinds of outrageous gains for their products, but BHR dosen't do that, but make no mistake their product research and development is all about giving you RX8 products that outperform the oem stock products, not just outlast them.

Mazda and many other manufacturers over the years haven't listed actual hp numbers to avoid liability and risk penalties of rules and gov't regulations . It doesn't mean the reality of what hp these engines produced wasn't so.

 

I take it to mean that you aren't going to rise to the challenge to prove the point?

 

Don't bring it up again unless you have something real for us ............... please.



BTW I ran stock coils on my 300whp turbo setup for 3 years . I then switched over to the D585s .
Guess what ......... same performance .