Needing some advice or opinions please! Spark plugs, Nitrous, Rear Exhaust.

[TTMERC]

Wanting to replace my plugs has anyone done this that can say how involved this is also any spark plug recommendations? Thinking about going a step colder for the summer and possibly Nitrous use. Anyone seen nitrous on these motors? I have Filters and Off road downpipes on on the car with stock mufflers in the rear. Has anyone seen gains with replacing the rear mufflers? Are they restrictive? One more question do you know if 17" rims will fit on my CLS550 for the rear?

[Sticky]

I think a 17 will clear but you just need to find the right offset and that is the tough part.

Regarding plugs, a step colder is usually the rule of thumb for nitrous but depending how aggressive you get it's not necessary if just running a small shot and depending what type of shot of course.

What were you thinking of doing?

Changing the tear mufflers won't bring you much of anything other than a sound change.