additude

I have a 97 LS and have been running Bosch +4's in it for over 4 years and haven't had a problem. I think it's about time for a plug change and was wondering what the consensus might be whether I should stay with the +4's or go with maybe Denso Platnium 2's or Denso Iridium?

Any comments that would help in my decision are appreciated.

Thanks,

Wes

Lexusfreak

Wes,

Your LS came stock with NGK laser platinums, NGK # BKR6EP-11 (NGK stock # 2978). Gap is .044. The correct Denso iridium part number would be PK20R-11. I would personally change to one of them & get away from Bosch as overall, they are much better choices over the +4's for your LS 400. Get prices at several major auto parts stores before you buy. Hope this helps!

additude

The Denso site says I should use IK20.

http://www.densoiridium.com/find_par...&action=Search

Is there a difference?

Wes

Lexusfreak

Yes, the IK20's are only good for 30,000 miles.......the PK20R-11's are OE iridiums are rated for about 4 times that.

The Denso site says I need IK20's for my 01 ES too, but the correct OE Denso is SK20R11.

additude

Denso Iridium is IK20; and the Denso Double Platinum is PK20R11

Iridium cost is $11.99

Double Platinum cost is $6.82

Are you sure you have your numbers right?

Wes

Lexusfreak

Yes, Iridiums are quite a bit more expensive over platinums, but that Iridium won't last nearly as long as the double (laser) platinums. I'd go with the PK20R11's as I don't think you can get the long life iridiums.......remember, the IK20's are only good for 30k miles & double the price.

And sorry my mistake, the PK's I mentioned in my previous post are platinums not OE iridiums. My bad. But yes the numbers are correct.

sha4000

iTrader: (1)

i just took my original plugs out at 120k and the # is sk20r11 and they were still good i just changed them b/c it was recommended maintenance

Lexusfreak

I beleive sha, your 98 LS was the first year Lexus started using Iridiums so I am not 100% sure Wes can use them in his 97.....something Wes might want to call his Lexus dealer about.
Just wondering how much did the plugs cost you for replacement?

vin 78

yeah, you should try the Denso Iridium's. I have mine in my es for over 60k miles now, and their still in good condition.
A little expensive, but definitely worth it, considering you don't have to replace them until in at least 90,000 miles (the es is a little hard).

Lexusfreak

According to Denso, the SK20R11's are good for 100,000 miles.

sha4000

iTrader: (1)

i didnt get the iridium plugs manly b/c i just wanted to take the old ones out to see what kind of condition they were in which would also tell me how my engine is running. i dont really know anything about iridium vs. platinum. so i went to autozone and got some ngk v-power plugs thats also recomm. for my car to see what the difference would be in acceleration and starting. im not too concerned about changing plugs every 60k or 120k b/c i do all my own maintenance or whatever else needs to be done short of dropping the engine or tranny b/c you really need a lift for some things. anyway i changed the plugs like 2 days ago and it seems like the new plugs give better accel.(of course) and starting. but im going to run them about a month and if i dont like the fuel economy ill def. chnge them back out for the OE iridiums which cost 4x more. i personally need info to justify that much money for a plug. the iridiums are $9 on that denso site but most other places they are $13

Lexusfreak

I would have at least put NGK laser platinums in instead of the NGK V-power personally. But that's just me.

sha4000

iTrader: (1)

i hear you but that was the only other plug that they offered for my car esides the bosch and i wasnt going to get those. i dont really know much about spark plugs so i got the v-power. i probably wont keep them in there though.

Lexusfreak

I'd be courious as to the price between the long life Denso's vs. the NGK iridiums......that's comparing apples to apples.

sha4000

iTrader: (1)

the ngk iridiums are $7 in strauss while the denso is $13 everywhere else i checked(streets & online) except on the denso site which they are $9 as i stated earlier. do you think there is a big diff. btw the 2?