Replacing Spark Plugs in GT

[rottone]

I have a stock '03 GT. I am getting ready to replace the plugs and wires with NGK IX Iridiums and FireWires. It looks pretty tight - can it be done without removing any additional pieces? The procedure posted on PTCruizer seems to be for non-GTs. Any advice from experience? Also, I'm trying to decide what the best gap should be for the NGKs - .040, .045, factory .052, none of the above? Any help would be much appreciated.

[rszappa1]

You do not have to remove the intake. You will be able to remove the plugs.

[quicksilverdon]

Welcome to the forums.
Nothing needs to be removed - except the plastic piece at the throttle (it clips). I used a universal on the plug socket - made it easier. Did my daughter's '03 GT in about 20 minutes, going slow and careful.
Consensus is for smaller gaps - I've read many use 0.028 (specially those that went to Stage 1), and even Chrysler put out a TSB revising stock to 0.040 - I went with 0.038, and all is fine.
Use a dab of anti-seize on plug threads, and coat plug boots with dielectric grease, you'll be surprised how hard it is to pull the old plug wires out.
One more thing - takes a good bit of force to seat the wires right - on plug and coil end - you'll feel a click..

[rottone]

Thanks for the advice, guys! I'll give it a shot this weekend.

quote:Originally posted by rottone

I have a stock '03 GT. I am getting ready to replace the plugs and wires with NGK IX Iridiums and FireWires. It looks pretty tight - can it be done without removing any additional pieces? The procedure posted on PTCruizer seems to be for non-GTs. Any advice from experience? Also, I'm trying to decide what the best gap should be for the NGKs - .040, .045, factory .052, none of the above? Any help would be much appreciated.

[rszappa1]

Again I will say...The TSB that was put out is for the NON TURBO Engine only....

[rottone]

So, what has worked best for people with NGKs on a stage 0 GT? I have seen everything from factory .052 to .028 discussed. If I go .040, is there any downside compared to .052?

quote:Originally posted by rottone

I have a stock '03 GT. I am getting ready to replace the plugs and wires with NGK IX Iridiums and FireWires. It looks pretty tight - can it be done without removing any additional pieces? The procedure posted on PTCruizer seems to be for non-GTs. Any advice from experience? Also, I'm trying to decide what the best gap should be for the NGKs - .040, .045, factory .052, none of the above? Any help would be much appreciated.

[littleblueGT]

I found that my 03 GT had the best all around performance with the NGK 2315 (LZTRA6AIX-13) gapped at .045. I tested in increments from .052 to .035. I just changed plugs for the hell of it after putting 17,000 miles on the iridium plugs I put in the NGK V power (4306, LZTR5A-13), and there was a loss in performance, both were gapped at .045. I had 2 sets of 4306 plugs, but had to order more iridiums which I will be installing shortly. Two heat ranges cooler seems to agree with my turbo, and the iridiums last a lot longer!
[?]

[rszappa1]

You say you had a loss of performance...Did you actually dyno the engine to compare or is this just a "Feel" you have. i find it hard to believe that if the spark plug is firing correctly that there would be a loss in performance with the NGK V groove plug....
[8]I

[littleblueGT]

There was less pull especially at 80 MPH. Before if I touched the throttle while doing 80 MPH she pulled hard and quick to 90 + MPH, with the 4306 although smooth it's just not there.Off the line is smooth with 4306, but just doesn't pull as hard under the same throttle pressure or position, and there is no indication of missing.All I can say is my PT seems to like the iridium plugs much better and 2 ranges cooler than stock. The iridiums with 17,000 miles pulled harder than fresh V Powers.Funny that sparkplugs.com only show the heat range "5" for PT Turbo and SRT-4,but don't show the heat range "6" that I use which seems ideal.

[rottone]

Well, I replaced the plugs and wires, gapped at .040. It is much smoother, but there seems to be less power so I will try regapping to .045 or .052 when I have a chance. However, I noticed motor oil on the threads of all the plugs I removed, and could see some oil on the spark plug holes. Is this normal? If not, what kind of problem is likely and is it covered by the 70,000 mi powertrain warranty? The car only has 35,000 miles (outside the bumper to bumper).

quote:Originally posted by rottone

I have a stock '03 GT. I am getting ready to replace the plugs and wires with NGK IX Iridiums and FireWires. It looks pretty tight - can it be done without removing any additional pieces? The procedure posted on PTCruizer seems to be for non-GTs. Any advice from experience? Also, I'm trying to decide what the best gap should be for the NGKs - .040, .045, factory .052, none of the above? Any help would be much appreciated.