getusum

iTrader: (42)

I just purchased a set of NGK iridium ix tr55's...It says they are pre-gapped to 40..sounded weird to me, I've always gapped my tr55's around 50-55..I tried a search on this before asking, but the search engine is acting up...funny how it always seems to do that...Any help is appreciated...

JZ28

iTrader: (3)

I would also love a definite answer to this question. These plugs are sitting in a pretty significant parts pile at home, waiting for me to get home from Iraq. They will be going in along with a ported throttle body, LS6 intake, TR224 cam, long tubes, and a whole mess of other supporting parts. I would hate to do all that work and have my $7 a peice spark plugs causing me problems cause they are not gapped correctly.

brad8266

iTrader: (23)

gap tr55's at .050-.055


.040 is more for the TR6 light blown/nitrous users

JZ28

iTrader: (3)

So just because they are iridium plus, it should not make any difference, right? Has anyone heard of having problems using the iridium plugs?

LSWon00

iTrader: (3)

I've had both the Denso IR-16s which are like the TR-55IX's and now TR-55IX's and have never had any trouble. I checked the gap to ensure .55 on all plugs and they work fine.

The Denso IR-16s are $15 per plug so be glad you have the NGKs.

JZ28

iTrader: (3)

Thanks for the reply. I will gap them at .055" and go with it.