Ok so i have a couple questions about my gap that i cant seem to answer with the existing threads about this subject.

2003 Evo VIII TBE, MBC @23psi, Tune

I was recomended to buy the one step colder plugs the 8 series and to gap them at .022. I did this and the car seemed quite flat with the new plugs compared to the pretty beat up 7 series plugs that i pulled out of the car and i think these were gapped to something a little larger like .025

So i increased the gap a little bit and it seems to be responding a little better.

My question what should i be running for plug and gap for what i have. I see alot of .022 gap size recommendations but it didn't seem to work well. What is everyone else using at this boost level?

thanks for any info guys. Ive been searching for a while with contradicting results.

-Ethan

 

At that boost .025" should be good.

 

Stock Gap, Stock Plug is fine for 23psi and your listed mods.

 

So should i go out and buy another set of plugs and get the stock 7 series? Or will the 8's that i have in there at stock gap be ok?

Also is the stock gap .025 im assuming?

At what boost should the gap be decreased?

Thanks!

-Ethan

 

you are on the wrong heat range and .24/.25 is fine.

 

A one step colder plug is overkill for your application. Remember the factory
preset boost amount is about 18.5psi, so going up to 23psi really isn't enough
to facilitate a colder spark plug. Also the optimal plug gap can vary greatly depending
on many variables. Myself and many others have experimented with different gap sizes.
But considering your list of mods and boost level I would recommend a .024 gap width.

 

One what type of application would you recommend the colder plugs?

 

Around 100hp over stock!

 

Definately with Methanol Injection and or high boost setups.

 

Missing zeros: That should be 0.024/0.025".

 

when you do buy the plugs they are not pre-gaped to that setting. so just don't throw them in and call it a day. Tap it -n- Gap it.

 

i think a 1/4" is a bit excessive

 

Yeah - but just think if you had the coil power to light that gap??

 

i always forget to type the .024