Spark Plug

[zlilz]

I was doing some poking around the engine and I noticed that on the bank of sparkplugs on the driver's side is Denso while the bank on the passenger's side is NGK. The 91 ls400 now has about 151,000 miles and I'm going to change all of the spark plugs. I have searched the forums and can't find a definite answer of which plugs are best. Which one of the following spark plugs should I get? Is iridium significantly better than platinum?

Iridium IX -$6.99

OE style laser Iridium -$7.99

OE style laser platinum -$7.99

G-power platinum -$2.99

I was thinking of maybe the OE style laser iridium???

Thanks

[dcfish]

I was doing some poking around the engine and I noticed that on the bank of sparkplugs on the driver's side is Denso while the bank on the passenger's side is NGK. The 91 ls400 now has about 151,000 miles and I'm going to change all of the spark plugs. I have searched the forums and can't find a definite answer of which plugs are best. Which one of the following spark plugs should I get? Is iridium significantly better than platinum?

Iridium IX -$6.99

OE style laser Iridium -$7.99

OE style laser platinum -$7.99

G-power platinum -$2.99

I was thinking of maybe the OE style laser iridium???

Thanks

I would replace with oem only, These cars are very sensitive in the plug dept.

[zlilz]

Would OEM plug be the laser platinum or the laser iridium?

[fencera]

I have been looking into this also and I think I am going to use these: Brisk Premium LGS ($105 w/ shipping for all 8).

Has anyone else tried these out? It seems like a good product and one of the easiest and cheapest performance "mods" ever.

A dyno'd review was done here: http://www.mustang50magazine.com/techartic...sk_spark_plugs/

And while I am not particularily interested in the HP gains (if they would even be noticable in our cars), there should also be increases in fuel efficiency which would be nice...

[dcfish]

Would OEM plug be the laser platinum or the laser iridium?

Contact a dealer.

[chilkoot]

i'm surprised, I thought it was public opinion here that NGK Iridium IX were the way to go. That's what I put in my car, she purrs now.

when I picked them up at Advance the guy there told me they were the natural progression of OEM, as they didn't make exact copies of the original denso's anymore. he may have meant the denso iridiums.

[UCF3]

I believe the OEM is Bosch Platinum. I wouldn't recommend the Iridium; it doesn't last the full 60k miles.

[OmarG]

I used denso double platinum plugs. I bought em for a steal on ebay but you should be able to get them for about 7-8$ each. NOT FROM THE DEALER! Even my toyota dealer charges 13+ for denso plats. pretty sure those are oem. like 99% sure.

[dcfish]

I believe the OEM is Bosch Platinum. I wouldn't recommend the Iridium; it doesn't last the full 60k miles.

No bosch in lexus, #90919-01178 Platinum only...... Anything else is at your own risk.

[zlilz]

chilkoot: Did you have the original plugs before you switched to the iridium ix? When you say "purr" do you mean the engine is smoother and/or better acceleration?

[cmshoot]

I use the NGK Iridium IX plugs. My 2000 LS400 runs great on them.

[chilkoot]

chilkoot: Did you have the original plugs before you switched to the iridium ix? When you say "purr" do you mean the engine is smoother and/or better acceleration?

I did a major job to my car recently, part of which was plugs. I see a huge difference in the way the car runs, but I only drove it 150 miles before I changed everything. The plugs I pulled out were the originals with 130k on them.

What I meant before was that the iridium ix's I installed seem to be a solid component of a now well-running car. This is first impressions, I just finished two days ago.