lt1z28camaro

iTrader: (2)

Well, I have been told by couple ppl that my tr55xi's are too hot for my setup. How much of a difference will it be when I swap in a step cooler plug? Right now my car randomly just pulls rough.. I don't know if this is related to the plugs I have in it right now, but USUALLY the car pulls extremely smooth, but once out of every 10 or so WOT it pulls rough and not near as hard. I don't know a whole lot about plugs and the differences.

I aleady got some acdelco plugs platinum a step colder (not sure on part #) but they are gapped at .50 should I gap them to a diff. size or are they fine as that? Also, tonight after adjusting the rocker (most likely the problem is I think I gave one too much turn after zero lash and making i do this) But at low rpm and you give it about half throttle the car shakes like CRAZY. I'll probably re-adjust them, but just curious.

So tired of this thing not running right! haha.

LM97Z

iTrader: (4)

I would make sure the valvetrain is adjusted properly, this is very important, especially with a race cam, on the plugs, sure, it wouldn't hurt going i step colder, but i would run the NGK TR6s gapped at .035", you really don't need a platinum plug, just a good ignition lol.

lt1z28camaro

iTrader: (2)

Seems like nobody is too sure on how much preload you should set. I've read anywhere from 1/8 to 3/4 turn. . They're adjusted at 1/2. But I've read that you should adjust them at 1/8...That just doesn't seem like it would be enough.

Dave J

iTrader: (2)

I dont see why the tr55 is too hot for your setup
are you spraying?

lt1z28camaro

iTrader: (2)

I'm not spraying, I guess it's due to the egr/air taken out so it sparks hotter with the stock like plugs and with the cooler plug it levels it out? (still a bit of a noob..)

koolaid_kid

iTrader: (21)

I agree about the NGKs, but he already purchased plugs, so it is a moot point. Gap should be the same regardless of plug type. I run my TR6s at .035, but I also have a turbo which may affect the setting.
OP, I have two books, the factory manual and a Rebuilding The LT1/LT4 Engine book.
The rebuilding book says tighten it down untile the pushrod just stops being able to rotate, then add 1/2 turn preload.
The factory manual says tighten to 11 ft/lb, then 90 degrees more.
Not sure which would be more accurate, however.

xx_ED_xx

iTrader: (17)

Yup I adjust mine to 1/2 a turn after zero lash. IF you are running naturally aspirated. Then you want a fairly warm plug. turbo nitrous etc you want a colder plug. I am not a fan of the platinums. I change my plugs regularly. SO I dont need 100,000 mile plugs