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tommyturbo
07-01-2010, 11:17 PM
Ok, I have been searching around on here, but there are so many opinions and most of the set ups are so much wilder than mine.

89 Lebaron GTC 2.5 turbo automatic, converted to intercooled using stock T-II Parts, with a FWD computer set to 14 psi.

Noticed that in hot weather computer seems to be pulling boost probably due to knocking.

Since I have only had the car a few months and have no idea of it's maint history, figured I'd do plugs and wires.

So what plugs would be good for this set up, I gather a step or two colder is good, but can anyone give me some suggestions?
Force Fed Mopar
07-01-2010, 11:48 PM
One step colder is good for you, if not stock. In NGK plugs, GR-4 is stock, GR-5 is one step colder.

You may want to check/replace the coolant temp and intake air temp sensors, in case they are not reading properly. (assuming you have a intake air temp sensor, not sure how complete your T2 swap is)
GLHNSLHT2
07-01-2010, 11:59 PM
Autolite AR51's. cold as RN6 champs, run great on a stockish motor too because of the cutback electrode promotes better flame propagation.
tommyturbo
07-02-2010, 12:15 AM
Thanks, I'll look into these. No charge air temp, left it with the 89 2.5 wiring, but all other parts are T-II, intercooler, hoses, radiator, airbox.
turbovanmanČ
07-02-2010, 01:17 AM
My wires with RN9's or the NGK iridium version. AR51's also work.
ShadowFromHell
07-03-2010, 02:27 PM
I would change the plugs, but if you are running a stock IC, its heat soaking. Thats why its pulling timming. A plug change may fix it but dropping the base timming a degree or two may be what you have to do to fix the problem. Do you know where it is set now?
tommyturbo
07-05-2010, 02:30 AM
I'll have to check it, as far as I can tell it's set to factory.
ShadowFromHell
07-05-2010, 01:26 PM
That would be the first place to look for me then. Id set it at 10 to be on the safe side.
tommyturbo
07-13-2010, 05:05 PM
plugs and wires, and cap and rotor done this last weekend. Plugs were really worn out, and the rotor was too. Much smoother, more responsive, and it's not pulling the timing and boost like it was before when I really get on it. Still need to do the timing belt at some point though. I will wait to fuss with timing until then.