Rear Plugs...

[Toofastgtp]

1st what is the best plugs
2nd what is the best way to get to the rear plugs
last this car is gonna be stock so.....

[Gemmer]

I like ACdelco rapid fire #8s, but they are getting hard to find, may need to order them online.

preferably park on a slope with the front of the car pointing downward. Pull off the weather on the back of the engine bay. Unbolt the dogbone mount, and pull the engine forward...I like to do it with a friend pulling the engine, some people use a ratcheting belt to hold it in place.

After you do it once, its easy

[Lyle's GTP]

If you got cash, NGK Iridium is what I run and they have been great. Platinum plugs don't seem to last at all. But I think the cash consensus is that the AC Delco Rapidfires are the most value. As far as changing them in your car goes, you have nothing to worry about. You don't have to rock your engine forward, that was only an issue one other year GTP's. You can get to the back ones with a couple 3/8" drive extension bars. You will have to pull the rubber strip from the sill on the fire wall. But other than that, it is an aluminum top end so be carful. Make sure that your motor is stone cold when you change those plugs. One thing that may be a good idea is to blow out the spark plug holes with compressed air before you pull the plugs. Just to make sure you don't get any crap down the cylinders. Then turn them out about 3/4 turn, and then spray some WD-40 down there and let it soak for a couple minutes to lubricate the threads. When you install the new ones use a torque wrench, I think 20 ft/lbs is perfect with that length of extension.

By the way, you are fortunate enough to have the simplest LQ1/Car combo to work on.

Good luck

Lyle

[bud36light]

Ahhh if you have the LQ 1 its not going to rock forward. If it does then you HAVE to replace the motor mounts also. That means they are way beyond shot. Theres a thead here about the easiest way to get the rear plugs. Run a search.

[ez112]

NGK Iridium. That's what I'm gonna buy.

[bubba81]

Go to autozone and pick you up a set of wobble extensions they will allow you to get the plugs out real easy, as for the plugs AC Delco should do fine. Oh yeah, the plugs wires come out easier if you remove the weather stripping on the back of the engine bay. Hope this helps.

[dohcfiend]

i have a 94 lumi and all i have to do is remove the weatherstripping and use a long extension. after you break them loose and turn them a few times, them take the ratchet off and loosen them all the way using your hands.

i think they are replacing rapid fires with platinums. the 2 dealers i went to didn't have any rapid fires. nor did the napa's. the best deal i found on platinums was gm parts direct located in the links section.

[Lowerd1]

Use the regular AC DELCOs! Hardly anybody here requires race plugs, Iridium plugs or anything like that. Get the $0.99 a plug Delcos.

As for changeing them it take 10minutes to do all 6 of them. Take the weather stripping that seals the hood in the back. Bend that metal lip straight up right behind each plugs or Grind that off. Now take a Long extension and change the plugs. No rocking the engine or anything. Easiest way to change it. When you are done bend the metal back down and reinstall the strip or just reinstall the strip if you grinded it right there. 10minutes tops and not even breaking a sweat!

[Crimson Fury]

if you still have problems getting past that metal lip, cut notches into it above where the plug is and go from there. the rapid fires are now #12s. the box still has 8 on it. might want to replace the plug wires too. i had an easier time replacing those than doing the plugs(mainly the rear center )

[blk92z34getrag]

The only problem with using u-joints is you risk slipping and breaking the sparkplug.

What I did was remove the weatherstripping and cut little notches in the metal with a hacksaw. Not only can you run a straight extension, but you've also performed WEIGHT REDUCTION!!!

-1lb. = -.001sec. off the 1/4 mi.

And I'm sure about 6oz. was removed!

But that's just my suggestion (notching the metal lip for the weather stripping), I've broken spark plugs before, and it isn't fun. It has no adverse effects either.

[Lyle's GTP]

With the 1994 GTP you won't have to bend or cut ANYTHING. There is enough clearance for a straight extension with no U-joint. All you need to do is remove the rubber strip.

Lyle

[bmlawson]

in my 93 z-34 i didn't have to bend or cut anything. just make sure that you plug in every vaccum line and electrical connection. i just did mine today and it can be a pain.it makes it much esier to replace them if you take the plenum off. it really isn't that hard to do actually.

[95gtp]

Come on now, dont make such a project out of changing spark plugs!

First why spend all the $$$ on high dollar plugs in a V-6? Like I heard in this forum before, AC delco plugs work great. Ya aint going to see any giant boost with the high $$$ plugs.

Use a piece of hose to remove the plugs in the back, first loosen then up with a plug socket and get that out of there, then get some hose that will slip ovet the top of the plug and loosen it up and out, do the same in reverse to install. Its that easy!!!

If you work from the passanger side you wont have to remove anything, rock the motor, or remove the weather strip, cut or bend nothing.

This is probably one of the easiest things to do on the DOHC monster. If you thing its hard to change spark plugs just sell your car and get a slant 6.

[Gemmer]

Ahhh if you have the LQ 1 its not going to rock forward. If it does then you HAVE to replace the motor mounts also. That means they are way beyond shot. Theres a thead here about the easiest way to get the rear plugs. Run a search.

Mine moves about 1/4th of an inch when you pull really hard, just enough to fit my slightly too fat ratchet extension =)

[billjoyal]

from what ive read in your other post about your waterpump, you have leakin lower intake gaskets....if you have to change them, changing the spark plugs will be sooooo fkn easy it'll scare you. You have to take the plenum off to change the lower intake gaskets and as soon as that plenum comes off, bingo there you have it, 3 rear plugs in plain sight....i saved myself a headache when i finxed the leaky O ring yesterday and popped in new plugs....i had about 1500 more miles on the old plugs but that wasnt enough to intimidate my wallet. I agree also on the regular AC Delco plugs, you dont need no rapid fire shit.......you dont see much more gain.....most of the gain people see in there car is mental HP, meaning they think its there because of a "Rapid Fire" high dollar plug when in all reality, it ran the same with the old plugs.....just my opinion...