I know many people say that spark plugs, ignition wires, ignition coils, etc are good upgrades on our minis.

But I am a noob, so I just want to know why these are good upgrades? what does it really improve? worth the money? etc.

anyones explanation would be great!

Thanks!

 

The items you listed don't really make much more power if they are in good shape...but if they are not in good shape...lots of power can be lost...or the car can fail to start.
Spark plugs should be changed on a pulley car just like a JCW IMO, that is at each Inspection/Service...and should be run one step cooler if a pulley is installed to make optimum power....this is the one ITEM in your list can can certainly add some power and drive-ability to your car if they are needed, or your car is modded.
Plug Wires are a bit of a wear item in two ways, one is as they age, the internal resistance goes up...the second is the rubber parts degrade due to heat exposure (they are so short, the insulation and rubber coating in likely to be compromised before they fail testing with an OHM meter)...the OEM ones are fine...but there are many quality ones available that offer some advantages....better color, perhaps lower resistance to help the system gain some efficency, better silicone sleeveing etc.
As for the Coil...the stock one DOES tend to corrode on the tips....and they do fail with age...many use the stock with no problems on very High HP MINI's....but if you are going to replace it, why not get one with more power...it doesn't hurt (if the spark plug gaps are appropriate for the coil voltage)...and the aftermarket ones are usually cheaper than OEM, some add a bit of color, have Brass tips to prevent corrosion.

Some folks have their car idle better after swapping these parts....but if the parts that came off were all in great shape...the changes are likely negligible...but if the parts have many miles, some age, corrosion, and they are not working as well as they should, they could cause problems.
Replacing them will not hurt...if they they need to be done...do it...but you are unlikely to find much power.....Except for the spark plugs....there you may be able to find a bit of power.

 

I always love your posts, Zippy.

exactly what I was looking for.
Thanks!

 

For the stock coil, if the ends are corroded (which is common for #3 from what I have seen), you can use some carb spray cleaner sprayed onto a shop rag, or just use a brass brush to clean the terminals. From all that I have read on here, you're wasting your money buying an aftermarket coil. Jan from RMW has attested to this over and over. Stock coil is more than capable in some of the more modded MINIs here.

Agreed on the wires. Stock is good; they will degrade over time based on mileage. Plugs upgrade is only really necessary if you get a pulley, CAI, and tune. Only then will you need to get something like NGK BKR7s.

 

Good tips so far. Stock HP cars don't need anything but stock components well-maintained. High HP cars will need colder range plugs to keep from being damaged during the use of that extra power. Aftermarket coil packs are generally never needed, the stock coil pack is excellent and reliable well past 300wHP. The only reason you'd need a more powerful spark is to maintain complete combustion with super-crazy-mega modified engines [applies to almost nobody]. Spark plug wires; you just need one stock or better [like Magnecor, not like Nology]. There is a lot of crap and gimmicks out there, don't fall into crazy shaped spark plugs or "amazing new breakthrough" spark plug wires or mystery boxes. Spend that money on quality upgrades!

For the average "bolt-on" setup [15% pulley, CAI, exhaust, ECU tune], a very good setup is Brisk Silver Racing plugs [or NGK Iridium IX or OEM JCW] along with Magnecor KV85 [or stock] wires and the stock coil pack kept clean.

Cheers,
Ryan

 

Ryephile speaks the truth...
...and I have nothing to add other than my own personal experience. 5 years ago I bought all the ignition goodies (Nology, MSD coil, colder plugs). I now have 1.5x the HP and run stock coil, stock wires and Brisk plugs. In fact, my MSD coil showed corrosion, so don't think they are immune from that--in my case worse than stock.
Over the last 5 years I've done almost *every* mod to my Cooper S (and I mean it) and I have a garage full of spares, wasted parts and left overs attesting to what works, and what's a load of old horse manure... Ignition mods fall in the horse manure pile.

 

Thanks guys! I just ordered my NKG colder plugs from Amazon. $30 with free shipping. Can't beat that! I'm glad to hear that all that other jazz is unnecessary unless your existing coil or wires are bad.

 

I noticed some high voltage warning on the coil. When cleaning, do I need to disconnect the battery so I wont get jolted?

Thanks.

 

No, you should be fine so long as the engine is off. No voltage goes through at that point because there is no fuel to ignite.

 

When I replaced my stock NGKs with Brisk Silver plugs, I noticed an instant gain in the torque/low end HP range... The car accelerates so much smother now.

I also replaced my stock wires with Magnecor 8.5 MM wires so the combination was definitely helpful. My car has 86k miles on it though, so I am sure that has something to do with the "gains"... Like zippy said, probably more that I just gained back what was being lost due to old worn out parts. The previous owner of my car did not do any work on the car himself, and certainly did not mod it. I can't wait to get a CAI, pulley and exhaust, but with another boy on the way, it's going to be a while...

 

Yes, your gains are most likely due to new vs. old worn out parts. Stock plugs would have been fine. Aftermarket wires are really not needed (I debated this one extensively, but I decided to keep stock wires after reading all the threads in NAM).

CAI, pulley, and exhaust sound good. Don't forget a tune afterward. I recommend Jan at RMW. And please don't sweat an aftermarket coil. The stock one is good to 300 HP.

 

From reading posts in the past, i feel obligated to remind everyone to torque their plugs to 25lbf on a cold head. Unless they like blowing plugs.

 

Yes, it's always best to torque plugs down on a cold head. Thanks for the reminder.

 

Hopefully if we say it enough, the "I blew a plug" thread will stop expanding.