green_henry

I've noticed some occasional pinging, and I'm wondering whether it makes sense to try a colder spark plug. In particular, I'm considering the Denso IK22 (versus the IK20 which would be the stock equivalent).

Most of my miles are highway miles and like to keep the tach >=4k most of the time, with vtec excursions whenever the road opens up. Since I don't do a lot of stop and go driving, I'm guessing that a colder plug may be the ticket.

JTso

iTrader: (2)

What octane are you running? Have you taken out the plugs and examine the condition?

green_henry

I'm running 91, which is the best I can do in California. I removed the plugs last night and they look like they're on the hot end based on pictures I've seen elsewhere (like here ).

Since I only have 12k on the car, they're not at the point where they're being damaged (noticeably, anyway).

green_henry

Looking into the details on the colder plugs, the gap is smaller. I'm not sure if this rules them out as an option. Anybody know?

Meanwhile, in the interest of experimentation, I ordered a set of Denso IK20s. These are the same heat range as the stock NGKs, but the electrode is slimmer on the Densos -- in theory, they may perform slightly better. I doubt that there will be much of a difference, but I think it's worth a try; while they're expensive as far as spark plugs go, they're inexpensive as far as mods go. Hopefully, they'll get here by Saturday and I can post an update on the weekend.

925tsx

let me know how they are, i wanted to change the plugs to platinum but i found that the stock ones are iridium, which is a better conductor than platinum, and they are good for 100k.
so i was gonna change them out anyway, and put the same ones in..just so i have fresh plugs.
but at $15 a plug, ill wait a lil longer.

chuson

Let us know the result green_henry~!
Anyone else have input or experience on any other "better" spark plugs??

green_henry

I installed the plugs tonight (fast shipping and good price from sparkplugs.com), and my first impression is that the engine definitely seems smoother. Smoother acceleration and smoother idle. Nothing major, mind you, but noticeable.

The interesting thing was that the Densos are definitely shorter (smaller reach) than the NGKs. This surprised me because according to the web site, they're both supposed to have a 3/4" / 19mm reach. I confirmed that the NGKs are 3/4", so the Densos must be closer to 5/8" (I measured the NGKs, but didn't feel like removing the Densos to measure them). I noticed this right away and was concerned that this would be a problem, but the engine started without any hesitation and ran great. Could the shorter reach account for the smoother performance? Does this somehow make them a better match with the Comptech header?

Also, I made a point of disconnecting the battery prior to changing the plugs. Supposedly this resets the ECU so that it will "learn" the new configuration (something like that). This, by itself, should not account for the smoother idle as I have done this at least once since I installed the header.

With shipping and tax, this mod was less than $60 and took less than 15 minutes. I guess it's possible that the car is running better just because the plugs are brand new. Maybe a brand new set of NGKs would have made the same difference. Possible, but I think the Densos are cooler anyway with the slimmer electrode and U-groove.

JTso

iTrader: (2)

How many miles on the old plugs? It could be just the new plugs restoring the original performance. Dyno?

green_henry

Could be, but the old plugs had under 13k on them.

chuson

I hope some one can confirm with me, but did I just read that the stock TSX spark plug are NGK Iridium??? I found that the Denso Iridium are quite expensive, and planning to get the NGK Iridium IX and a set of spark plug wires. Any suggestions???

MrHeeltoe

iTrader: (1)

If you want plugs that will last forever, get these:








I used to burn through copper plugs in 1500 miles on my CRX. And those were heat range 7. I put some of these in and I am pretty sure I will never need new plugs again.

chuson

Hey MrHeeltoe, are those NGK Iridium IX spark plug I mentioned?? or are those A'pex Racing Plug (picture background)??? Any differences???

I did a search and found that the NGK Iridium last very long, somewhere like 60,000 KM.

MrHeeltoe

iTrader: (1)

Well, they are the A'PEXi plug, but obviously they are NGKs, so maybe they are the same...

Alin10123

Dang... pinging? Did you ever put regular gas in there?
Maybe try disconnecting the battery to reset the ECU and see how that goes. It shoudn't be knocking especially at 13k miles and premium fuel.

green_henry

I never put regular gas in there on purpose, but I think it's possible that the gas station may have had the wrong grade in their tanks. Since then, I've tried to stick to just two or three (other) gas stations, and I haven't had any problems.

Meanwhile, I'm still happy with the Denso plugs.

junktionfet

This is an old thread but I wanted to refresh it...

I've noticed that my 1200 mile-old TSX pings audibly on occasion, and if I'm paying close attention I can feel mood swings in performance. My friend with the '03 TL-S has a much more noticeable pinging problem. We both use 93 octane and have isolated certain area gas stations that sell the best gas.

A couple years ago NC's metropolitan counties were switched over to a fairly aggressive low-evaporation formulation of gasoline. The problem with this fuel is that it has a much higher tendency to preignite. Anyone with a high compression or forced-induction car will notice the drop in performance when using this fuel for the first time. Sometimes it seems almost worth it to go out of state or at least into a rural county.

So with that said, I have considered trying spark plugs that are one heat range colder. Perhaps that will be more compatible with this tainted crap they call gasoline.

According to NGK, my TSX is supposed to use a PZFR6E plug, which appears to be a single-ground electrode platinum tipped resistor plug with a heat index of 6. I'd like to try to BCPR7ET. It is pretty commonly available (which is something to consider), and is a 3-ground electrode copper tip resistor plug with a heat index of 7.

I don't care to spend a lot of money on Iridium or Platinum. I hate spark plugs with rare metals and small tips. Plus the copper tip plugs can be safely gapped without running the risk of breaking something.

kane.s2k

Instead of doing something so agressive as changing the plugs for something colder, you can try reducing the plug gap. I would reduce them 0.05" and see how it goes. If you are still noticing pinging, go for one step colder. Be careful with gapping iridium because the tips break off very easily.

I also recommend the NGK over the Denso's because some batches of denso's have the ceramic portion not be upto snuff and actually crack off. That might have just been a bad formula back before but I don't trust it anyways.

Copper plugs and iridiums generally are equal in cost because the iridiums can last so much longer. I usually buy coppers and swap them every oil change or every other. This lets me monitor the condition of my plugs instead of doing a "set it and forget it" and be in trouble later on.

aaronng

If you are reducing the gap, remember that the stock gap specified for the TSX is 1.1mm, in case you need to "put it back" to stock.