I have vf30/dr650/ur785s/utec/txs shorty, had installed ngk iridiums one stage colder and car ran ABSOLUTLEY great for a few hundred miles, now is lacking a lot of topend....

checked compression/cam timing/no boost leaks/drivability seems fine/no cels

should i just try a set of coppers? anyone else had a similar expierence?

should be the other way around ...
copper- short life/platinum- longer life
unless you have way too much fuel in there and are fouling the plugs

coppers are ALOT cheeper

but keep in mind coppers deliver slightly better performance, and they're cheaper. that's a rare combination in the automotive world. :huh:

I'd look elsewhere for your answer.

Ehhh, you sure about that? My car detted horrible on coppers. Not as worse on Platnium and not at all on NGK Iridums. NGK says the Iridums are better which jives with what I have observed. shrug

Ehhh, you sure about that? My car detted horrible on coppers. Not as worse on Platnium and not at all on NGK Iridums. NGK says the Iridums are better which jives with what I have observed. shrug

Well just reading the FAQ, it says that coppers should produce more power. but they're also a plus because of their cheap prices, and I wouldn't mind changing plugs every year.

Copper plugs = more power, but erode so much quicker than iridiums/platinums they aren't good for a daily driver... especially considering that changing our plugs isn't as straightforward as an inline 4 or inline 6.

I know of some high horsepower Supra's that SWEAR by copper plugs. One guy picked up 30 whp switching from his new Iridiums to coppers, right on the dyno.

def

Copper plugs = more power, but erode so much quicker than iridiums/platinums they aren't good for a daily driver... especially considering that changing our plugs isn't as straightforward as an inline 4 or inline 6.

I know of some high horsepower Supra's that SWEAR by copper plugs. One guy picked up 30 whp switching from his new Iridiums to coppers, right on the dyno.

def

30whp? that's pretty hard to believe. :huh:

Well yeah they erode quicker, that's why you have to change them so frequently. They should be good for about a year or so though, and I'm willing to spend plenty of time working on the car. :)

30whp? that's pretty hard to believe. :huh:

Well yeah they erode quicker, that's why you have to change them so frequently. They should be good for about a year or so though, and I'm willing to spend plenty of time working on the car. :)

Were talking about an 800 horsepower car... a little easier to believe?

def

Hmm ok. I believe you. Supra is a WAY different motor. On an EJ207, I gained 50whp switching to irridums right on the dyno. Back when I had an 1820, on 91 octane, I could not get past 230whp on coppers and Platnuim heat range 7 plugs. I detted horribly. Put in heat range 8 Irridums and gained 50whp, switched to AVO450 and went up 130whp on 91 octane from where Coppers left off. About 30whp more than a larger Green Ver7 RA BTW. Out here in our AZ. climate with our gas, before people get all ill over that statement. :lol:

Perhaps the Irridum benifit is unique to Ver8 motors due to the compresion. Or even my motor only. It is possible. My Ver8 motor basicly would not run on Coppers or Platnium 7's. USDM VF34 easily made more power. Oh, my USDM VF34 motor detted horribly at 250whp out here on 91 as well with Copper 7's. Shrug.

Stick with what works for you I guess is the take away here. :cool:

Were talking about an 800 horsepower car... a little easier to believe?

Yes it is. Hmm....guess I'll have to check out them Irridiums.