I would like to change my spark plugs. Is it worth changing my plugs? What plugs should I go with? I was thinking about the denso iridium plugs. I read mixed answers about plugs...that it doesn't make a difference to stick with the stock plugs...but if I can do a $30 or $40 mod and get better hp and mpg i wanna do it. thanks for any advice...kirinzon

 

Hey, bud. First up, no. Next up, none
If you'd run a search (hint, hint ), you'd have found a dozen threads saying the same thing- Mark W.

 

Can you direct me to an actual thread, because if I run a generic search "spark plugs" I get many post that are not direct to the point. Thank you... respectfully...Kirinzon

 

No. Okay, no again

 

If there is no benefit I wouldn't change them, but I would like to hear both side of the argument and maybe some tech stuff on why plugs that claim to be better than stock suck...kirinzon

 

The talk about better spark and all that is hooey. You need a spark, air, and fuel for combustion. It's that simple. Bigger and better spark means nothing. Dependable spark is key. The stock plugs are sufficient for this job. If you hear some techie saying different ask them to explain the science. You'll hear little.

If you are not having any problems don't mess with them. JMO, but backed by owning cars for almost 40 years. I have an Accord that I kept the same plugs in for 220K miles. The MPG and performance never changed. I had a Chevy Cavalier that went well over 100K before I sold it. Same thing. Plugs were fine. If there is no problem in the engine these new titanium plugs last almost forever. Back in the old days with old plugs they seemed to burn up or need cleaning on a regular basis.

 

^ Not entirely true. Some plugs are certainly better than others. It often depends on the application, though. Honda uses NGK and Denso iridium plugs, which are pretty much as good as it gets. For applications that use cheap plugs (pretty much nobody anymore, but older cars certainly, with copper plugs), an upgrade CAN help. But with a modern, coil-on-plug, OEM iridium plug setup, there's VERY little left on the table. You'll often LOSE power and fuel economy with new plugs. I've dyno tested this again and again and again. The power boost most people feel is ALL in their heads.

Now, if your plugs are poorly chosen for that application, or fouled somehow, yes, a swap may help. But Honda does a good job with their plug selection, and yours likely aren't fouled, so there's not much to gain- Mark W.

 

Sorry- forgot one of the key points I wanted to say- bigger and better spark means a LOT, if your stock ignition is weak. For instance, on an '88 Mustang, 5.0L with a fresh rebuild, we did the initial dyno runs after break-in with OEM ignition- it was pushing just over 300 WHP, and 350ish ft.-lbs. of torque. With an upgrade to a MSD distributor, cap, rotor, and Accel 300 wires (BEST wires for 5.0, period), and the same plugs, we picked up 15 WHP, and over 40 ft.-lbs. of torque. No other changes, and only 50 more miles on the engine. So yes, bigger and better spark DOES mean a LOT. That's in an application, however, where a lot was left on the table stock. In the Fit, there's VERY little that can be gained, and it's probably all in the coils, not the plugs- Mark W.

 

That's what I mean. Today's plugs are seldom, if ever, an issue. They simply fire and keep firing. The quality of pugs today is better than days past. Just another thing about today's cars that I love. It's like the deal with 100K no tune up guarantees now. I have to tell ya, this has been the rule for probably 15 years. You simply don't have to tune these things anymore. Electronic ignition and fuel injection changed all that. You also seldom have to align some cars. My 2003 Accord has never needed alignment. Today's car is very low maintenance If you have one that is get rid of it, and if you have one that seems it's not, but you have your mechanic telling you it is get rid of him.

 

Driveway tune ups used to be an oil/filter change, new air filter, points/condenser, plugs and a timing. We used to do them every other month in someones drive during fair weather just to hang out together. The girls loved it.

These days it's tweaking the add-on's and looking for something else to do for most w/ the 150K+ service intervals being as they are. I'm glad my FIT was given good sparker's by Honda - looks like a PIA to have to change them and it's comforting to realize I never will.

 

That is for a plug that isn't suited for the power supplied. That is not the case here. Sufficient spark is sufficient spark. Bigger than that is not better.

 

thanks for not slamming me to hard and the education. I thought the fits had a standard desno and I was going to upgrade to the iridium. What plugs are in the fit again?

 

As I said, the plugs in the Mustang were NOT changed. Everything else was. That's what increased the voltage supplied to the plugs, resulting in more complete combustion- Mark W.

 

Oh I remember the day. Always adjusting or replacing points. Messing with choke settings. Cleaning/changing plugs (Cause my last adjustment was too rich). There was so many things to do. Yeah, looking at cars today I wouldn't want to mess with plugs. I do work on brakes though. Disc brakes are a breeze. Haven't seen a drum in a while. I'm curious as to how hard they are to mess with now. Guess I'll find out. Working on my 4-wheel disc Accord was EASY. I replaced all the calipers on it. Bleeding that system was about as easy as it gets.

 

Yup, that's the trick

 

For my 2010 they list:

Spark Plugs
NGK: IZFR6K13
DENSO: SKJ20DR-M13

Not sure what's under the hood...

 

Good question. I have to check. Even if they are "just" platinum there is nothing that would justify changing. If they are less than platinum, which I really doubt, then get them the heck out of there, LOL

 

Those are both Irridium.

 

I'm thinking your quest for HP will bring others on. This is the freakworld and it's full of some very keen talent and well informed folks doing amazing things. Search around a bit and hook yourself up.

 

I had irridium in my 03 Accord. They were there till the engine blew at about 220k. Dropped a valve or something. He is a picture of the number one plug after the disaster.