spark plug ?

[jareds99slobra]

i know theres probably 1000 of these out there so bear with me guys im on my phone and it takes forever to upload and look so i figured id just post a new thread.


i have a 99 cobra 109 on the odo but the new aluminator motor has 14k on it. anyways i took it to pro-dyno they suggested i switch the stock plugs for some ngk while it was down there to be tuned. so i did, well the other day i was cleaning up the motor and decided to pull the plugs to check and see how they looked i realized they are the ngk tr55 vpower which is a cheap copper tip plug.

my ? is should i switch them out for platniums or iridums and the gap on them were all 45 now of my knowledge the gap on these cars should be 54 correct?

will it hurt to run these plugs like this?
will i see any gain if i throw in a platnum or iridum plug?

 

[01yellercobra]

I'd set the gap to .054. Supposedly the copper plug gives a little better spark. The main reason I know of for running the platinums is maintenance intervals. I put platinums in the wife's suv and I run copper plugs in my car.

I'd just regap what you have and run them until they wear out. And I'd ask the shop why they went to the smaller gap.

 

[Brutal Metal]

The TR-55 is ther best plug to run in a NA Cobra, keep what you have!
I gap mine to .048!

 

[Lefty10]

I run Autolite 764's gapped at .054

 

[01yellercobra]

The TR-55 is ther best plug to run in a NA Cobra, keep what you have!
I gap mine to .048!

But you're blown. He isn't so he doesn't need to close the gap.

Wow..that first sentence is bad.

 

[99MystiC]

From Sean Hyland How to build max performance. He recommends NGK TR6 and gapped at .035 for NA max performance and .030 for FI applications.

 

[01yellercobra]

I would imagine max performance also means high compression. That changes the pressure inside the cylinder.

 

[99MystiC]

It doesnt mention anything about compression.

 

[Brutal Metal]

Wow..that first sentence is bad.

Oh yeah? what did you want me to suggest a Bosch Platinum?:shrug:
And I'm gapped at .048 NORMALLY ASPIRATED! Did the same with Every 5.0L I've owned as well, I think .054 is too wide, don't really care what the owners manual says! Whenever I ran a gap that big the car felt like crap!!
And it's not like I'm the only one that closes it up a bit, Plenty of others do!

 

[01yellercobra]

Oh yeah? what did you want me to suggest a Bosch Platinum?:shrug:
And I'm gapped at .048 NORMALLY ASPIRATED! Did the same with Every 5.0L I've owned as well, I think .054 is too wide, don't really care what the owners manual says! Whenever I ran a gap that big the car felt like crap!!
And it's not like I'm the only one that closes it up a bit, Plenty of others do!

I meant the comment I made about being blown. It was early for me. Way back when I was N/A I ran the plugs gapped at .054" and never had an issue. But I was running Autolite platinums.

 

[01vert]

COPs can run a bigger gap than a regular distributor / single coil setup so with a close to stock motor the factory gap or slightly smaller is fine.

Copper is the best unless you are worried about running plugs for years with no replacement. Run coppers and replace them yearly, easy enough to swap them out in an hour.

 

[jareds99slobra]

wow lots of mixxed reviews haha i guess i should just throw in some iridums so i dont have to worry about gappin um

 

[01vert]

So you trusted a shop enough to have them tune the car but not enough to set you up with a set of good plugs? Think about it. They are not going to stiff you for $20 by putting in cheap plugs if they have any kind of decent rep. Keep what you have.

 

[jareds99slobra]

True but the guy who put the plugs in was a new guy and the guy who tuned the car had nothing to do with the physical work he just knows the computers and how to tune that.

 

[urdustd]

Keep the copper core plugs they will give you the hottest spark. Platinums are for longivity and emission purposes. They closed the gap to make sure you will fire as a large gap can misfire or be "blown out" before igniting the mixture. You can run irridiums (they work as well as copper, but 5x or more the cost) but why spend the money as a good copper plug will last 12 mo or 12k miles and they are easy to change on a 4V motor....but in the end it's up to you!