Has anyone used the Bosch Platinum +4 on their S? Would you recommend these plugs for the S?

 

all bosch plugs have carbon build up problem...
OEM rules~.

 

I just put them in my car a couple weeks ago. so far so good =)

 

i've used those plugs before and they worked fine. Can't say i could tell any improvement but it did the job.

 

AFAIK, they are just a gimmick. The spark will occur between the 2 points of least resistance, which will change over time. If anything, you know the spark will never occur below the tip, which is where you would want it. I can't think of any reason why you would want the spark to shoot sideways from the tip, especially if it is going to change sides all the time.

Do some searching on Denso Iridiums. They have been great for me, and going with a slightly colder plug (IK24) has given me better performance in the heat.

 

Just get NGK Greddy IRIDIUM Racing Spark Plugs. Bosch are fine but ur driving a high performance car, and iridium is recommended by Honda.

 

Actually,

I'm pretty sure platinum tipped plugs are stock. Which IMHO is the best plug you can get for an NA s2.

 

Define "best". Longest lasting? Least misfires? This topic has been talked about a zilliontimes - a search is your friend, but i feel charitable.

We did a lot of testing on the SC'd Cobras, because spark blowout and/or misfires are a real issue with a boosted car, esp with aftermarket undersized drive pulley, and no knock sensor. We found the Denso Iridium had the least misfire, but that the TR6 copper plugs, which had essentially the same basic design without the dink center electrode, were nearly as good for a fracion of the price, making twoce a year changes reasonable.

On a car like the Subaru outback, where the boxer engine makes some of the plugs a pain to get at, I use the platinum.

On the S2000, I use the Denso Iridium, one range cooler than stock. I am NA, do not drive in traffic much, and have not had any fouling problems.

Here are links for the technically inclined among you:
http://www.nbt-brunei.com/part/parts/denso_plug/

http://www.svtlightnings.com/sparkplugmisfires.htm

 

Thank y'all.

 

Very informative chart. It looks like the Bosch performs quite well comparing to the stock. Just I had suspected, the SplitFire is a piece of junk. Once, half of it broke off when I tried to change plugs and I had to have my old car towed to a garage to take the bottom half out.