Hi

I would like to know the different spark plugs available from denso or ngk that can be fitted to a standard lighting.

would the ngk TR6 or denso iridium IT20 be ok, or others?

Thanks

 

On a stock Lightning I'd run the autolight's that came in it, start modding and I'd run TR-6's.

 

I'm located in europe and it' easier to find ngk or denso, and I would like to know if the TR6 are the first step above the standard ones.

Thanks

 

I thought TR-6's Was same as stock ??

 

ummm no not really. Id go with the NGK TR-6's. they are the best if you ask me

 

I was told once that with stock boost you should run NGK TR-5's, if you have a pulley and a running a few #'s over stock then the TR-6's are for you. I just put in TR-5's on my stock Lightning and they work great! Cheers!

,Marc

 

Is the length of the spark plug thread on the 99 00 lightnings different from the newer ones, as the thread on the head cover was shorter?

 

only the Ford replacement plugs are different.

On a stock motor run the TR5 as it is the stock heat range.
If you put a pulley, change the boost, and or more mods that increse boost above ~10lbs change to the TR6 as they are one heat range cooler and will not damgae the motor at higher power levels like the TR5's will due to detonation.

 

Hi

Could you please explain how it works with the 2 different lengths of thread for a same engine? When you fit aftermarket spark plugs will there be a part of the tread that will just stay out?

Thanks

 

im running stock boost and have tr6's, i saw no change in performance....

 

Ford has a redesigned plug that is tad bit longer to take advantage of the 1 single thread that most other plugs fail to catch at the bottom of the plug hole, as far as the heat ranges you can run a TR6 on a stock L but you might run into a slight miss at idle and or fouling of the plugs due to it being too cold and not completly buring off the carbon buildup as it should.

IMO the $8.00 per plug that Ford Charges for the "new style" is not worth it and is NOT a fix for the blowing plug problem, only a bandaid.

TR5's for a stock L
TR6's for a modded L upto 650 hp range (my personal opinion)
Br.... for a modded L 650+

 

This Ford redesigned plug is not the standard motorcraft plug then?
Do you know it's part number?

Other than that what I would like to know is if the aftermarket plugs you can get for the lightning have some part of their thread that is useless and would stay out of the engine thread, as the standard plugs uses a shorter thread, and the part that stay out is unthreaded.

I would also like to know if the newer 03 lightning with a different head that uses more thread use a different standard spark plug compared to the standard 99 lightning, as the standard 99 spark plugs would not have enough thread, and would of course use more thread of the aftermarket spark plugs?

I ask this as I'm not used to fit long thread spark plugs in an engine that requires short thread spark plugs, and I would think that they would come loose much more easely, but maybe not?

Thanks

 

I was wondering about that... you mean with the tr6's there is a slight miss??
I feel it missing a tad at idle... if this is why.. .than i am relieved...


Thanks

 

I think that the OE part number has been superceeded by the newer design in the Ford parts catalog ie. dealer computer.

the 99-02 heads only have 4 threads and one of those threads is unreahcabel by most sparkplugs as it is at the bottom of the plug hole, where as the 03-04 heads have 8 threads that start much higher in the head to allow the plugs to be the same length but have more thread engagement.

the length difference is negligable about 1 1/2 threads b/w the two ford plugs

the factory plugs are the same for all years (except for a batch that had the wrong plugs installed)

with the cooler temp of the TR-6 and it being a copper electrode it tends to lend itself to a low rpm 'miss', its not really a miss as much as a "Rough Idle" condition. B/C of its cooler temperature it tends to load up or foul at low engine RPM and cause the "rough idle" condition...that is why some like the denso's; they tend to have factory like smooth idle...but also cost an arm and a leg, with no real performance benefit beyond a better idle.

However a weak coil pack can also cause a slight miss but if it goes away ~1000RPM or more its more than likely caused by the plugs.