LS325ci

iTrader: (3)

I was looking at what plugs to get. tr55 is what the general concensus seem to be.

My auto parts store only carry tr5 which is only a gap difference vs tr55.

so can I just gap the tr5 to .55 and it will then be a tr55?(well not by part number ofcourse.)

is the gap even worth the trouble? for stockish ls1

RPM WS6

iTrader: (3)

Why not just order the TR55 and start off with a correct gap?

LS325ci

iTrader: (3)

poor planning on my part, but i have this weekend off and so I figured its the best time to do the plugs. if I order it I doubt it will make it here by the weekend.

N20zuki

I believe the difference between a TR5 and TR55 is the gap they come. TR5's come at about .040 and TR55's at .060 ...

Buy the 5's and re-gap them...

ragtopz28

iTrader: (57)

^I agree^...plus you should always gap prior to install. They are never all the same. Also, if you drop one, check gap again (or better yet get a new one, the porcelain can get a hairline crack and not run right). btdt

RPM WS6

iTrader: (3)

I agree. But I just don't prefer to change the gap by such a large amount on a plug when it's possible to get one with an initial gap that's closer to what is desired.

RevGTO

iTrader: (12)

I read somewhere that GM is now recommending the smaller gap for LS1's. TR5's will work fine ... you could open them up a little if need be.

Fry_

Almost every part store I know of can get most parts by the next day. Also if the person behind the counter isn't smart enough to figure out what your asking for tell them you need 8 spark plugs for a 96 Grand Prix with a 3.1 they'll be tr55's.

RPM WS6

iTrader: (3)

The recommended smaller gap (.040") was for the updated tip (iridium) plugs. They worked fine like this when I had them in my '02.

I'd stick with the wider gap for a copper tip, IMO. Anything between .050" and .060" has always worked well for me.

thunderstruck507

iTrader: (18)

I had iridiums gapped at .060"

then tr55 gapped at .055" then later .060"

then replaced them with tr5 gapped at .045" and .050"


There has never been any noticeable difference in driving, starting, fuel mileage, WOT, or anything else with any of these changes.

ragtopz28

iTrader: (57)

My experience as well^. I ran tr55 @ .055. Now running BR7's @ .032
Zero noticeable differences in drivability.

RevGTO

iTrader: (12)

Likewise. I've always gapped mine at .055-60. I pulled my last set of TR55's at 35k and they looked brand new. I'm going for 50k on the current set. But I can see going with a smaller gap because, if anything, it may widen over time.

z28boycali

Tr55 gap anywhere from .50-.60

WS6wanted

My tuner told me to install tr6s @.035. Car has lid and longtubes and drives great

murphinator

iTrader: (2)

that would be a typical gap if spraying nitrous is in the mix.

RPM WS6

iTrader: (3)

TR6s are a colder plug. No need for that with minor bolt-ons only, they'll just need to be replaced sooner and offer no advantage on such a mild setup.

WS6wanted

Thats what i told the tuner but he is the one that plays with these motors all day. I have iridum tr55 if they die quick.

Chris25

iTrader: (1)

Have mine gapped at .055 running fine here.