Oracle1

iTrader: (1)

If using a step colder plug are there any changes to the current MAP, namely timing?

Jeff_Jeske

iTrader: (66)

No. But you'll need to beat on the car more during daily driving or they will carbon up. For grins check the plugs at your next oil change and you'll see what I mean.

I'm curious what plugs you are using. Most 9 guys say finding copper replacements are a PITA.

TouringBubble

iTrader: (2)

Yeah, the Denso replacement I once found is no longer listed anywhere for the IX ...

TeStUdO

iTrader: (6)

He is probably using the 1 step colder iridiums. I dont think they are making the 1 step colder copper plugs yet.

C6C6CH3vo

iTrader: (9)

Been using BPR9ES for about 8 months with no plug loading from carbon. This is on a VIII though.

Answer to question is nope.

Jeff_Jeske

iTrader: (66)

^ Aren't you steam cleaning the combustion chamber?

TeStUdO

iTrader: (6)

Yeah, with all that meth injection I am sure you dont have to worry about the carbon buildup

Oracle1

iTrader: (1)

Intended plug is the NGK R7438-8.

Inprogress

iTrader: (30)

You could also use Denso IKH24's, they cost 1/3 of the NGK's...

recompile

iTrader: (38)

I honestly have no problems with my stock plugs... I ran 27 psi on 100 octane for 2 tank fulls and hard driving without a problem.

I'll just continue to replace them every 10k to be on the safe side.

MZP@TeamD

Colder plugs does not have as much effect on timing as gaping the plug does.For over $50 per spark plug (R7438 ngk racing) you should not worry about spark plug problems,i'm sure you can put the money for better use.

steadly2004

iTrader: (19)

So, how would a smaller gap effect timing? would you need to advance/retard it?

mplspilot

iTrader: (7)

Gap affects the ability for the plug to create a spark at certain cylinder pressures. The more pressure you have, the smaller gap you will need, otherwise the plug might not fire.

Choice of plugs and gaps will not affect the timing directly.

If you run ****ty/incorrect plugs and have to reduce timing because of misfire issues to cure the problem of too high cylinder pressures, then by switching to correct plug/gap/heat range you will be able to run more timing, because your chamber will be better cooled and you will have spark all the time. But again it's more of an indirect effect.