Spark Plug Preference

Im pretty close to being due for 36k check up with Ford on my 99 Cobra. Id like to upgrade the plugs to something a little more high performance but not sure which fits such an application. So far the car is bone-stock, looking for a performance normally aspirated plug.

BTW no NOS either

i like Motorcraft platinum plugs, gapped to .050

Im pretty close to being due for 36k check up with Ford on my 99 Cobra. Id like to upgrade the plugs to something a little more high performance but not sure which fits such an application. So far the car is bone-stock, looking for a performance normally aspirated plug.

I hear only good things about NGKs from the racers. Bosche is alright, but dont get autolites or splitfire. those are crap. Actually most racers i know only run NGK. Of course they are about $7 a plug but oh well.

No question - Denso Iridium plugs run the best in Mustang GT's or Cobras. They burn cleaner and are good for 2-3 HP over platinum or stock plugs. They come pre-gapped and you can get a set on e-Bay the cheapest for around $75-85/set of 8. I tried all the other plugs and these are the best in my 2000 GT 4.6 2 valve. This was verified recently in a spark plug test on StangNet: http://www.stangnet.com/tech/lee50guru/dense_tech.html

No question - Denso Iridium plugs run the best in Mustang GT's or Cobras. They burn cleaner and are good for 2-3 HP over platinum or stock plugs. They come pre-gapped and you can get a set on e-Bay the cheapest for around $75-85/set of 8. I tried all the other plugs and these are the best in my 2000 GT 4.6 2 valve. This was verified recently in a spark plug test on StangNet: http://www.stangnet.com/tech/lee50guru/dense_tech.html

The article shows the NGK's were only good for .4HP and 1.6 ftlbs gain over stock motocraft plugs that had 5,000 miles on them.

And the Denso added 2HP on a G-tech cause we all know how accurate those are......

Spark plugs are like everything else mired in a shitload of opinion and not enough facts. I have seen every brand spark plug in high hp(500+HP) cars. The brand doesn't matter it's having the best heat range and gapping for your application.

Spark plugs are like everything else mired in a shitload of opinion and not enough facts. I have seen every brand spark plug in high hp(500+HP) cars. The brand doesn't matter it's having the best heat range and gapping for your application.

Couldnt have said it better myself. BTW I havent had any problems out of autolite or champion plugs. I do prefer autolite over champion though, they seem to burn cleaner and last a little longer.

Couldnt have said it better myself. BTW I havent had any problems out of autolite or champion plugs. I do prefer autolite over champion though, they seem to burn cleaner and last a little longer.

I just heard this from a mechanic (for 27 years) and a oval racer with a camaro. Id trust them over any of the others because of experience. thats all. The guy with the camaro had asked pretty much everyone in the pits, and they mostly said NGKs. Oh well.

I just heard this from a mechanic (for 27 years) and a oval racer with a camaro. Id trust them over any of the others because of experience. thats all. The guy with the camaro had asked pretty much everyone in the pits, and they mostly said NGKs. Oh well.


That's fine but I could show you a ton of guys in the pits of drag tracks, circle tracks, road racing circuits that use Autolites, Splitfires, NGK, Denso, Champion, etc.., Like I said, brand doesn't matter.

Agreed with 351w and GTStang. The fancy plugs aren't worth the money(and they aren't cheap!). I just use good old autolites. Never had a problem. You definately won't notice less than 2hp.

Great - a bunch of barely out of highschool and twenty-something "experts". A bad-attitude moderator who doesn't moderate and feels the forum rules are for everyone else. I'm surprised you were able to follow and comprehend the discussion in the link. Sorry I ever entered this discussion. It's called an O-p-i-n-i-o-n. I'm outta here, losers.

Great - a bunch of barely out of highschool and twenty-something "experts". A bad-attitude moderator who doesn't moderate and feels the forum rules are for everyone else. I'm surprised you were able to follow and comprehend the discussion in the link. Sorry I ever entered this discussion. It's called an O-p-i-n-i-o-n. I'm outta here, losers.

Don't be mad cause I know more about the topic than you and you were made to look like exactly what you are.... a moron.

I'm sure all of us here will really miss your lack of knowledge. Good by and have a nice life of ignorance.

Ok I opened this back up but keep it to spark plugs guys. :smokin:

A spark is a spark. The more power crap because of running a high priced plug, to me is just that crap. You can run an engine on a dyno, one pull after another with the same set up, and guess what, you will not get the exact same reading on any of the pulls. There are too many variables working to come up with that reading. If you believe that you get more power because of advertising, its your money. I'll stick with the cheapos, and make just as much power, and save my cash at the same time.

I don't know...I'm scared of cheap stuff...but I feel the same way as a spark is a spark...so I tend to buy the 'in the middle' brands. You know..the 'cheap' namebrands, but still namebrands.

I don't know...I'm scared of cheap stuff...but I feel the same way as a spark is a spark...so I tend to buy the 'in the middle' brands. You know..the 'cheap' namebrands, but still namebrands.

Wouldnt what the manufacturer recommends be the best? Even aftermarket?

I always thought it was common knowledge that Mustangs runs best with Autolite or Motorcraft plugs?

I have tried many differenet plugs in my Mustang;
Autolite
Champion
Motorcraft
Bosch
Bosch Platnium 4's
NGK
Delco

For some reason I always end back up with Autolite 25's. They just seem to run better for me, plus it saves the wallet when I change my plugs every other oil change.

I run Autolites as well.

Some good comments here. I am in the same situation of needing to make a decision for the 1st set of plugs in my Cobra. I tend to like to stick to factory stock parts, but I do like platinum plugs (mostly because they seem to last longer and changing spark plugs more frequently than I have to is not tops on my list), and I have tried just about every brand listed above at one time or another. But then, I do not race the car on a regular basis. I did get a deal a few years ago and purchased a set of the Denso Iridium plugs for my GT fairly cheap from an Internet company no longer in business. They were nice plugs and ran fine, but I would not have purchased them for what I normally see them selling for. The choice is yours, and there are better things than spark plugs to spend the extra $ on. For street use and occasional racing, you probably would not notice the difference vs Autolite or Champion. Good luck with your decision.

Guys, what about Side Gapping? Anyone tried this? and did you feel/dyno any differently?

i like autolites