so my truck has 105K on the clock, is it time for new plugs and wires?

 

if they've never been changed I'd say so!

 

That would be a very GOOD idea.....

 

just changed mine a few weeks ago at 80k and picked up 2 mpg city and hwy and it idles better than before. Most people on the board here use the ngk tr55 plugs, I gapped mine at .055. MSD wires seem to be the popular choice on here too.

 

yeah as far as i know they are original, i've herd anywhere from .05 to .06 for gaping, anyone know?

 

i just put in tr55's gapped stock .060

 

gmpp red wires or msd?

 

You definitely won't get another 100K miles out of the NGKs though. LOL.

 

i remember a while ago people saying they gapped to .06 and the truck didn't behave right, then changed to .5 and everything was ok.

 

Definitely for performance & gas mileage. Did my bros 02 Silvy w/ 85K, orig. plugs. Sooty as sin, gaps were all over .060- .080+, way off & center electrode non-existent. He never did b4 & after to check mileage since he was afraid how bad it was, but did say it's improved. Have fun w/ pass. rearmost plug since that plate kinda gets in the way. Those who've done, know the plate I mean. U just want to beat the **** out of it, & no I didn't.

Don't know on NGK or...but for AC Delco Iridium gap @ .040. I check em all too. When he can, $$ tight, I told him get wires too. Took out Volant, cleaned & reoiled( also over on miles). Now maybe he'll let me learn how to tune w/my HPT on his. We have to compensate for Volant/ Corsa anyway.