Just curious as to everyone else's experience with average spark plug in relation to the mods they've done.

Even though I'd installed the last set (stock heat range) only 4.5K ago, the other day I noticed that the idle was kind of rough, leading to idle vacuum dropping a bit, along with a distinct increase in light backfiring during the first few miles of operation when cold. I pulled the plugs, and found that the leading plugs' electrodes were worn pretty good (as I kind of expected, although not for that mileage). Trailling showed some wear, although obviously not as bad.

However, about 4K ago I installed a Pettit ECU, and later added an M2 airbox. I had looked at the plugs about 2K ago, and the wear rate seemed fine. About 750 miles ago, I installed an N-Tech hi-flow cat. So now my engine has a usual list of bolt-ons: Pettit ECU, DP, hi-flow cat, RB duals, SMIC, Efini Y-pipe, and M2 airbox. Guess I'm just a little surprised at the increase in wear rate, so I'm wondering what everyone else's experience is. These plugs have not seen any track time either, and my driving habits aren't radical or anything. Only occasional full throttle through-the-gears bursts here and there on the highway and canyons.

After installing the new plugs, idle is back to normal, and a definite smoothing of low-end power, along with a very slight increase in low-end power/acceleration.

When my FD was stock, I had no problem getting around 6-9K out of a set of plugs before it started affecting idle, etc.

 

i've got just about every mod you can do except a single and ignition upgrades and my plugs seem to go aroun 4-5k, just depending on how hard i've been driving, sometimes i can get a little more out of them. i've got 15k on my new motor and i've changed the plugs 5 times, once was due to flooding. i've switched from using the stock 7's and 9's in platinum and use 9's, non-platinum ones and not only are they cheaper, but they don't appear to last any less. supposedly more conductive, but i think i need ignition upgrades to benefit from it. at least it saves ya a couple bucks per plug

 

Hi Kent,

Have not heard much from you lately. Where have you been?

I have a similar mod list as you, with no HF Cat. I have been changing my plugs at about 5k for regular maintenence. That's about once a year for me. The last time I changed them, they didn't look too bad, and the car didn't run any different afterward.

I suspect that we have similar driving habits. I have been using NGK "9's" (BREQ or something like that) on all four.

 

I've been running stock NGK 9's on my highly modded FD...probably for the good part of 6 months. I've upgraded ignition amp/coils and run a T-45S turbo with blahblahblah...you get the picture. Tuning the driving range is what will make the plugs last longer.

 

I'm going to switch my plugs after this weekend.. going to go with what you said.. Non-platium and just change them out every other oil change (every 1000 or so for me)..

I'm beginning to realize how important general maintainance is for your cars..

PHIL

 

Hey Adam ,

Fuggin' business trips and my job have been a serious timesuck lately.

Guess maybe I should try running all 9s. I've just been paranoid about getting stuck once in a while in L.A. traffic, and having a plug foul somehow due to the Pettit ECU's richer fuel mapping (yeah, I know it's probably stock down low, but the stocker is a bit rich as well). It must not be an issue if you're running it; no problems with warmup, etc.?

I would, if I had a wideband and an adjustable ECU... What is your average mileage in 6 months?

Thanx for the suggestion, spoolin93r1. I figure I'll stick with the platinums until/if I need an ignition upgrade due to more mods.

 

My commute to work is about 3 miles. The car is barely warm by the time I get there. No problems while running during warm up.

 

I ran 4 BUR9EQPs on my last 3d gen with a pettit ecu streetport fuel pump and all the bolt ons...the car ran rough until it was warm but totally totally drivable. No problems with the idle or anything oh and 9s just dont foul out all of the sudden for no reason they are like the stockers and get progressively worse.

If I were you id run all 9s and take them out at every oil change and clean them and use them until they go bad for you. Also every time you change the oil and clean the plugs switch the front trailing with the rear leading and the rear trailing with the front leading etc...


BTW my 94 is now single turbo and I redline it daily at some point its my only car. I premix about 7-8 ounces for every gallon of gas with valvoline 2 stroke oil tcw3 its amazing ****. Its been now ~4k miles and the plugs feel great, I believe the premix is keeping the plugs clean...maybe its also the water/alcohol injection thats doing it lol.

any way good luck and back to polishing I go

 

So, what do you used to clean your plugs??

 

well a spark plug cleaner of course...ask goodfella about it

if you dont have that I'd soak them overnight in carbcleaner (metal or glass cup cause the carb cleaner will eat through some things)

then use a high pressure air compressor to blow out all the shizat

then get some ~1500 grit lay it down on a flat surface and rub the face of the plug on there

I dont think that last step does much but I just like them to look new again before putting them in...I did this procedure on my last car 4 times in a row (every 2 oil changes cause I change oil at 1000 miles at most) and the spark plugs had ~8k miles on them and they were still rollin!

 

i do know that my car seems to run better without the platinums and they seem to last just as good, if not longer. anytime i'd go like a couple months without changing them and driving like normal, when i'd go to the track and run higher boost, my plugs would foul and make the car cut out. i haven't been since i switched to all copper, but i'm buying an hks twin power to hopefully keep that from happening. my car runs pretty rich, so i'm sure that helps the plugs foul so often. either way, our cars eat plugs, expensive ones, and we just have to deal with it

 

When I got my car I installed stock platinum plugs. It's been 5 years (6 months per year) and 30,000 km. Checked them this fall and they still look fine. Car still runs fine. I was surprised. No cats, had PFS PMC, now Power FC, HKS superdagger midpipe back, Magnacore wires, stock ignition coils/electronics, PFS intercooler and cold air intake.

Maybe I should sell the plugs as "forever plugs" ;-).

 

sorry to be bringing this back but how long do you guys usually go before replacing the spark plug wires as well?