-Seems as though my car stutters at higher rpm on higher boost where it never did before.
-Sometimes is a hard start
-RPM is lower on idle
-noticed vacuum is less than before
-and now the boost wont go past 1.4 bar

are my plugs on the way out or hanging by a thin thread?

Plugs are HKS heat range 8 one step colder...
See the thing is, the car is tuned on 98 octane and when i moved countries i had to run it on 95 octane... when on 95 I turned the EBC to zero and no problems there...

Was limited for time on temporary plates needed to get the car inpsected and registered yadi yada no raping of the vehicle just point A to point B stuff...

Now Ive got racing fuel in her and im getting the above symptoms...

As i'm preparing for the race gas tune i need to iron out this issue..

so heres the question...

If plugs are on their way out but not completely will it affect boost?

 

You might have a boost leak somewhere if your losing vacuum. You must run a boost leak test. It could be as simple as the hose behind the throttle body. One of the EGR hoses...

I always changed the spark plugs after each oil change. I can read spark plugs, but I can't read oil. haha. I used the cheap NGK coppers. I spent like 30 bucks for like 5 sets. And leave em in the glove box.

 

Pics of the plugs in question...

 

Which takes us here and another weird thing going on

https://www.evolutionm.net/forums/ev...e-results.html

 

Man they looklike crap!!

 

Change them now.

 

Also You should not be running race fuel unless you are tuned for it!!!! if your tuned for 93 then run 93, if your tuned for race gas then run race gas. Do not run a fuel that your car is not tuned for your going to cause more problems!!

 

Ok thanks guys...

They do look "normal" or a little worse than, nothing like the other destroyed examples

 

Picked up originals for now NGK ILFR7H as not to take a risk with the old ones....
Checked the gap on all 4 and they are all set at

0.50mm=0.019inch




Old plugs were between
0.031 and 0.029