Which plug(s) run the leanest on our Lightnings? I'm currently running NGK TR6's and I want to know which plugs to pay particular attention to.

Thanks,

 

I know some people that had a lot of trouble with the factory plugs.

I also run the TR-6s and have had no problems with them. The TR-5s run a little colder.

 

I'm not sure if the plug is going to run lean or rich. I think that's more of a fuel management program. Many owners have turned to the NGK as Kyle mentioned. You will get mixed opinioins. I installed NGKs after 20,000 miles and saw significant improvement in performance. R/S Dennis

 

The TR5 is one step hotter than the TR6. I've been told that the TR6 is 2 steps colder than the stock plug. This is the info supplied to me by Jim@JDM a couple of months ago.

I pulled my Splitfires about 3 months ago and installed TR6's. I dropped a little over a mile per hour at the track. I didn't suspect the plugs and wondered what was going on. Jim tried the Splitfires right after that and gained a mile per hour or better. He got the specs from each manufacturer to see what the deal was. The Split was a hotter plug and TR6 was colder. He tried the TR5 and said the MPH were about the same as the Split's. That's why he now recommends TR5's for non-nitrous motors and TR6's for nitrous.

What's crazy to me is the NGK's seem to burn leaner at part throttle daily driving. I will post a pic of all the plugs except the ND's and Torquemasters for comparison.

Here are the pics:

 

The motorcraft and the splitfires look about perfect but the other look like they are too "hot" for what you are running. A nice lite tan color is what you want.

BTW..the motorcraft looks a lil redish like you may have used some octane booster in the gas.

Andy G

 

Andy,

It looks like it had a little octane booster but it did not. I put a set of Split's in when I pulled the platinum's out and read them a couple of times on the same tank of gas. The porcelain stayed white so that ruled out the gas I was burning. I think the platinum electrode retained so much heat that it discolored the pocelain. BTW, I have NEVER ran octane booster or race gas in the L.

It's nice to that someone sees these plugs the same way I do. The TR6's seem to have a tannish look to them now but when I was pulling them to read 3 months ago they were grayer in color. As you can see the TR5 is ash white.

Here is a pic when I first pulled the TR6. This is the way it looked at the time.

 

Chuck,
were all these plugs gapped the same and if so what at. I had the same discussion with Jim and was planning on running thr TR-5s next time I change. I would probably gap them at .44. This is what my TR6s are gapped at and they run fine. Jim recommended .42
noelvm

 

Noel,

I just checked them all. After you have changed plugs and played with gaps as many times as I have you lose track.

The NGK's( TR5 & TR6), Autolite 103's and Splitfire SF10D's were gapped at .040". The Motorcraft 12FM1 (stock plug) was .046".

I just have a problem with plugs that are suppose to be colder running leaner in daily driving than 3 other plugs. I really need to do some WOT blast and take a reading. I know the Split's go leaner in this condition but I don't know about the NGK's.

It's time for another experiment.

 

Hey Chuck I just noticed you are in olive Branch. Im in southaven.
what color is L. I really havent saw any around here but I have saw several at Memphis Motorsports Park.

Anyway I dont know how true this is because Ive never tested the theory but a lot of the guys on the Mustang boards I hang out on say that the best time to read a plug is right after a 1/4 mile run.

If your motor {a/f ratio} is off then it will most noticable after a wide open run.

For example
If you are running lean at WOT then the plug will be white after the run but after a short time of normal driveing the plug will return to its normal color because under normal driveing the a/f ratio will return to normal.

If its rich {black plug} after a run then it will return to normal color because the a/f ratio should lean out after normal driveing.

Just a thought.

Andy G

BTW...What dealer did you buy your L from?

 

Andy,

I was the only black L (I believe) running at the Motorsports Park for the last few weeks before they closed for the season. My best time was a 12.65@107.93 on F1's.

I live close to old 78 and new 78 Hwy so I just go out and do about 5 WOT blast then park it. I pull a plug when it's cooled down. This is how I read the Split's at WOT. The chips lean them at WOT compared to cruising or daily driving. The NGK's are already leaner at cruising so if they do like the Splits they will lean even more. Then again I won't know for sure until I try it.

My main concern is running too lean during daily driving causing it to burn a valve or a hole in the piston. Of course it could do this at WOT but it sees a lot more daily driving.

P.S. Bought it at Homer Skelton.

 

Hi again Chuck

It seems odd that the chip would lean it out under boost/WOT.
I have a JMS custom chip in my car and it adds a lot of fuel under boost. Id be curious to see what the air/fuel ratio is on a dyno.
Like they say..lean is mean but it an also be dangerous but Im sure the guys that design the L chips know more about them than me..Im learning though.

Andy G

 

Chuck
One more question and I'll stop bothering you.

Did Homer come off the sticker price any?

Thanks
Andy G

 

They offered Xplan on the 01 L's. I thought about trading but they weren't offering much for trade in. I got my intercooler fixed and I dropped the idea.

 

Chuck are you still running the Splits or the TR5's?
The Splits look good.

 

THE FIRST PICTURES OF YOUR PLUGS THE SPLIT FIRE LOOKS LIKE YOU USED ANTISEIZE COMPOUND?? OR ARE YOU GETTING SOME ALUM FROM THREADS IN HEAD!! JUST COURIOUS. ARTIE