rfbznb

any ideas on what spark plugs i should use on my 02 gt?
is there any difference between copper,platinum,or iridium or is it a waste money to buy the ones that cost more?

as far as i can tell the motor is all stock other then a CAI and the exhaust is stock but im not running any mufflers on it.
if that matters with what type of spark plugs to use.

and is there anything else i should do to it when i change the spark plugs other then air filter and oil change.

cliffyk

The cheapest are the so-called "copper" plugs, which are just plain old nickel/chrome alloy electrode plugs with a copper core conductor. NGK was one of the first manufacturers to use copper as the core conductor, largely a marketing ploy at the time there are some advantages to the copper core; now almost all spark plugs have copper core conductors.

Precious metal plugs using platinum or iridium electrodes represent true advances in plug technology. The precious metal electrodes resist erosion from the spark current flow, allowing use smaller diameter electrodes requiring far less voltage for gap ionisation.

Iridium offers better resistance to erosion than platinum and has higher electrical conductivity (about 2X) than platinum, however in practical applications neither of these attributes produce any better performance--that's why the OEM plugs are platinum.

As to recommendations, the OEM Motorcraft single platinum plugs are good, The original AWSF-32P plug has been replaced by Motorcraft p/n SP493. I run Champion plugs in all our motorized things, stock # 3401 is their single platinum plug for our engines. They are both similarly priced at $2.50 to $3.00 each, a buck or so more than a conventional "copper" plug--however they perform better, for 3 or 4 times as long.

Here's a spark plug technical document from Weapon X, which I edited and expanded for them. It is of course tilted toward their iridium plugs, however the tech info is solid and applies to platinum plugs as well.

rfbznb

Thank you
looks like im going with platinum plugs
$970 left in my $1000 car budget what to spend it on