a friend of mine put bosch platinum 4's in his 1st gen eclipse and now it sounds a lil different, hard to describe but he claims it had pretty descent gains i myself would prefer denso plugs because i am almost positive they are better

my question is this if i purchased new spark plugs either denso's or bosh's would it be a noticable gain/worth it?

 

prolly 1 HP at most

 

they dont really give hp they just make it smoother

 

Spark plugs will get you increased response if the stockers are carbon fried. That's it. No more no less.

 

from the posts i read on here, the start up is smoother and some say it seems smoother at high RPM's, but as far as HP gain . . . you're not gonna notice anything

 

just kinda a follow up
the boost if any was not noticable the car accelerates and deccelerates smoother than before which is impressive i would expect a good boost from the denso irdium's if i had forced induction of some kind thats what they are made for mainly

 

Actually copper would probably be better if running boost...but this has been covered before so you can dig it up if you want to find more.

 

save me some trouble, why copper? put it in a nutshell

 

Save me some trouble and run a search. Plugs and copper/plugs and turbo...all very viable options. All about avoiding the detonation.