woody41

I am in process of fixing issues with service from local Chevy dealer. The guy I bought car from spent over $2000 at dealer in 2011 (3000 miles ago). Plug wires were ran wrong, burned one, one was not connected and another was broken among some of the issues. 3 of 5 plugs I checked are loose. I was looking at the AC Rapid Fire or the AC '100,000 mile' platinums. The right bank looks like a bitch so I want to do this right. Any ideas or preferences on spark plugs?????? 1991 L98 77,000 miles.

Thanks

Doug

TBSS/85vette

I used Rapid fire in my 1985 and they work fine.

crowz

Ac's worked great in my 86, completely problem free. I tried a few different plugs and had problems with it pre-detonating on me at cruising speeds when throttle was closed or almost closed.

Torque master plugs ran the best but they would detonated like mad at cruising speeds.

aklim

I'm a little leery of the loose plugs. I would like to know if the threads are still good or whether they are FUBAR. If they are FUBAR, you might be better off taking them off and doing a helicore on them. I believe my cousin told me he had a plug work itself loose and popped out of the head. Don't know why it happened but it might not have been set in right. The least I would do is chase the threads with plenty of grease. If that isn't right, you might have to take it out an helicore it.

HlhnEast

A/C D platinum #1 worked fine in my car. There was an article in I think "Super Chevy" magazine that did a plug dyno comparison and the #1s I thought had the best bang for the buck. SOP power seemed to increase but you know how that is. My car was having running issues (not plug related) and I pulled and cleaned them several times without problems.

I did go back to the regular stock R43S recently and they work fine as well. The car was designed for that plug and there really isnt any need to spend a bunch of money buying something that gains you a tenth unless you are tracking the car.

aklim

I would not buy a 100k plug since I dump them annually.

shootnstarz

I went with the 100,000 mile A/Cs on my 89, don't want to change them out anytime soon.

You are correct, the starboard side plugs are a nightmare, especially cylinder #1, under the A/C compressor.

If you have aluminum heads the threads are very long and it takes a lot of "worrying" to get them all the way out and back in. The port side is a piece of cake.

I slipped a piece of vacuum hose over the end of the plug so I could guide and turn it at the same time. It's a good idea to do one at the time so you have an angle reference when trying to rethread the tight ones back in.

Starboard side took about 6 hours, port side less than one. If you remove the compressor it would help a lot.

Rick

whalepirot

Dang, Woody. It seems a certain Chevy dealer needs to get out of the fixing business.


Having read time and again to NEVER grease the plug threads, I don't, but would consider some anti-seize. However, I have never found the need for it.

aklim

Grease burns up. Conductive anti seize won't

whalepirot

Yes, and can make a very good adhesive.

Never mind that the professionals who write the installs recommend against it.

woody41

Thanks, I had to use a piece of hose when I did the plugs in my GT 500, I had forgotten about that trick.

86C4Z51

Champion makes a graphite-based thread lube for aluminum heads that works well. Used it on air-cooled aircraft engines for years. I also use it for other threads as a light thread anti-seize compound (comes in a small plastic bottle with a brush in the cap).

Most anti-sieze you buy now is a silvery paste, which is readily available in tubes or tubs. I agree with never using grease. In any head, iron or aluminum, it cooks out and you'll have a helluva time getting plugs out next time.

I also recommend Magnecor spark plug wires if you have to replace your set. They'll last a lifetime, and an 8mm custom-made set is around $130 shipped to your door. http://www.magnecor.com/magnecor1/main.htm

vader86

Anti-seize and Rapidfires for me. I change roughly every 2 years. I would never spend the cash on a 100k mile plug in an old engine.

aklim

Even if you gave them to me free, I'd still change them or at least pull them out of the head. I am deathly afraid of plugs, be they glow plugs or spark plugs sticking in the head. Had that happen on a diesel motor several times where the thin glow plug broke off. Had that happen on a L98 where the stock plugs were probably from the factory. Had a hell of a time with the PB Blaster and flame wrench before it came loose.

For my diesels, I clean the chamber and remove the plugs every year to be safe. On gas cars, 2 years at most. Usually every spring I dump cap, rotor and plugs. Also mist spray the plug wires every winter.

vader86

I'm afraid of the same thing. I will randomly pull out a plug (esp on the drivers side) just to look them to see how the engine is running, and to apply some more anti-seize. I could not imagine having the confidence to leave one in there 100k miles.

aklim

Reading the plugs is going to be more complex with fuel injection. I did it a couple times on a Jetski but I'd go to the middle of the lake, change plugs, wot, read. For FI, I'd probably have an O2 sensor or pull plugs if I suspect coolant or oil leak.

I've seen seized plugs and they aren't pretty

86V

Why? Not being a smart ***....I'm just curious of what the advantage is?

aklim

Not having to remove the head if a plug gets stuck. Besides, I do all my service at the start of the season and in the winter, I Idle the car every 2 weeks to keep the battery charged. Spring means fresh fluids, plugs, cap and rotor. Cap usually lasts about halfway into the next season and I don't want to fix in the middle.

86V

Dang........I think I only changed the plugs and wires twice in 30 yrs. Then again the car only has 19,000........

beerme

That there is funny, I don't care who you are, that is funny stuff right there now.....