Hi I have an 84 t-type with a bit of a rough idle. The car runs great otherwise just have a noticable shaking of the engine at idle. I am running the ac delco rapid fire plugs #1. Is this why I am idling rough or do these plugs usually run good? What plugs should I run? I am running a high flow exhaust, cold air intake and an adjustable wastegate regulator at about 15-17 psi boost. Anyone with any advice please.
What DO most people run in these cars? AC Delco, Champion, Autolite, Bosch? Is it just personal preference? I've run every plug above (in SBCs)and can't tell the diff. I know, this is a different animal, but am curious.
As long as it isn't platinum, any good quality plug works well.
NGK U grooves seem to have been a hot item at one time.
AC CR (commercial grade) works well
Autolites work well
Depending on your upgrades and amount of boost
032 to 030 for higher boost seems to do the trick on these cars. I run 032 on ngkur5 or ac cr42ts they both seem to work well. I think the car runs about the same. If you don't have a lot of upgrades then try the ac cr43ts gapped at 035, this seems to work well on street applications for hot airs. The autolites work well too for street applications try the 23 gapped at 035. Hope that helps some.
Thanks guys. Advance Auto has the Autolite's for $1.20/plug. I'll throw a set in at .035" as soon as I get the engine back together.