86 IROC

iTrader: (14)

I currently have approx. 21K miles on the NGK TR55's in my car. I pulled two plugs at random today to see how they looked. I will post pics of them later. I took one from the #3, and one from the #6 cylinder.They both looked like the car has a lean condition. The gap had widened slightly from .052 to .056 on both plugs. I replaced the fuel filter today, it was very dirty and needed replacing. Still - I hear a slight detonation above 5K RPM, and the car seems to short shift around 5500 RPM. My car has just under 48K miles, recieves regular maintenence, etc. I have my MAFT set at 8% rich @ WOT, I bumped it to 10% today after the test drive in hopes it may help. I haven't run any top engine cleaner through the motor yet, but that looks like my next step.

I remember reading a thread about NGK plugs a while back and the general consensus was that the NGK's needed to be inspected around 15K - 20K miles and most likely tossed for new plugs. I may also replace the plug wires as well when I replace the plugs. Any insight, previous experiences, etc. would be greatly appreciated. TIA

99 Black Bird T/A

iTrader: (4)

I'd replace them @ 20K miles. My T/A has never kept a set plugs in it over 11K miles but I like to change stuff.

86 IROC

iTrader: (14)

Thanks, that's what I needed to hear. I'm considering going to TR6's next time even though I have no intention of running N20. I've been told by a few people that the car would detonate worse if I did that. Makes no sense to me, in my old L98 motor I ran colder plugs to get rid of detonation during the hot months here in FL. Wouldn't the same theory apply in this situation? Should I just buy another set of TR55's instead?

I'm seeing that quite a few people believe that the stock plug wires are fine and do not need replacing. To me, they are a wear item, and it seems like they would be about shot by 50K miles.

It's looking like I'll be doing: plugs, oil change, top engine cleaner/sea foam next weekend at the bare minmum... maybe some new plug wires too. I have yet to find the damn PCV valve on this car, I wanted to look at it and see if it is saturated w/ oil or not. I bought a new one, but haven't really been over the car w/ a fine tooth comb to locate the PCV.

86 IROC

iTrader: (14)

Here are some pictures of the #3 plug, sorry for the low resolution pictures - I wasn't paying attention to what setting I had my digital camera on. However, I think you can make out that the tip is green and the other side appears to have a slight amount of carbon built up on it in addition to having a green tip. I have never seen a spark plug come out of a motor with a green deposit on it. It almost looks like corosion, similar to when a copper penny turns green.

jamnut

iTrader: (4)

The plugs look like you might be a little lean. The pictures are hard to see detail in, but I don't see any little black dots on the insulator that would show that you were having bad detonation. Also I don't see a coating of oil like a lot of LS1's that I've seen, seems like your PCV is doing an all right job.

It looks lean, but not too lean, If you are worried about it take it to a dyno and have them do a wideband on it. It's really hard to tell anything from those blurry pictures. So everything that I see on your plugs could be wrong.

86 IROC

iTrader: (14)

Thanks for the input, looks like I'll just get another set of TR55's. I'll make sure to run some seafoam through the motor first though, it more than likely needs it with the mileage.

boomcase

Were you running any octane booster in the car.

86 IROC

iTrader: (14)

Nope, never. I only put 93 octane in it. The car has never had any nitrous on it either. I had a few people tell me green plugs = nitrous. I'm still debating... TR55's again? Or TR6's this time around?

Slowhawk

iTrader: (12)

They do look a little too lean but not to bad.
Since your running ported ends do you have your MAFT base setting to atleast 10%rich?A richer base can affect WOT pinging.
Also it is good to change the plug wires with over 40k miles on a hard driven car.

86 IROC

iTrader: (14)

I recently set it to 10% @WOT, I previously had it set to 8%. Haven't had the chance to listen for detonation, it's been raining all week. Looks like I'll just stay with TR55's instead of the TR6's as well. I struck out trying to find seafoam locally, NAPA decided it was a poor seller and pulled it. I'm stuck overpaying for the GM labeled stuff at the dealer.

C_B64

iTrader: (7)

the Top engine cleaner is only like $7 here.

Tally TransAm

iTrader: (17)

advanced auto carries them

i change them every 8k

86 IROC

iTrader: (14)

I just called my buddy that works for the Ormond Beach store, he said they only have TR6's in stock. Told me it would take a few days at least to get TR55's - if they can even get them. I got my last set through Summit, will more than likely deal with them again. If I order them through them, I know I'll have them in my hand by Friday so I can change them this weekend.

I hope the GM stuff is only $7 or less, those SOB's at most dealerships soak me for everything else - thus my reasoning for being apprehensive.

Thanks again to all who replied in this thread.

Tally TransAm

iTrader: (17)

the stores here dont usually stock them but the warehouse has them. and the stores got them with in two days. turns out though the warehouse is half a mile away from my house so i just pay for them at the store and pick them up at the warehouse. and this is in a shitty city like tallahassee

may wanna look into that

86 IROC

iTrader: (14)

Tried Advance Auto today, they tried to sell me TR5's, said that the TR55's are discontinued. My buddy wasn't at work, or I would have asked him. No biggie, just going to get them elsewhere so I can get the right plugs. TR5's would be one heat range hotter wouldn't they?

86 IROC

iTrader: (14)

Well, ordered some TR55's that they supposedly don't make anymore and a set of MSD 8.5mm wires. Still can't find any seafoam, and two local GM dealerships say that they don't carry top engine cleaner anymore. Is there some kind of a conspircay against me in Volusia county? I wonder if one of the sponsors on this site carries a similar product? I'll buy a damn case of it!