Changed Spark Plugs car runs horrible

[Mystic1199]

About a month ago had car dynoed an it had a small " blip " on dyno ...my tuner said maybe plugs or coil ..it was a small slight hesitation ...

So tonight I pulled the old plugs TR7s and installed TR6s (place I bought them from said the cobra calls for TR6s)

I installed them tonight and now getting a misfire on #8 so I swapped coils with another cylinder to see if problem went to that cylinder and it did not stayed on 8 ...I even put one of the old tr7s in to see if problem went away same thing ...car runs like shit under boost

I ran a snap on scanner on the car driving it around and watching the scanner out for a ride #8 was showing -39 on the graph....

So I'm lost here on where to go ...

 

[Zemedici]

Gap?

 

[Mystic03]

Gap?

+1 need mod list as well

 

[Mystic1199]

Gap was around 32ish I'll have to double check to confirm ....also forgot to mention after I swapped in the old tr7 I got same misfire on 8 and also one on 7 now

Mod list
Ported blower
2.93 upper
4lb lower
60s with sct maf
BAP


Should I just started over an install the old tr7s ?

 

[Mystic03]

Id gap to 28 and switch coils around sounds like one took a dump

 

[big dad]

I would check all the plugs. I've seen where a scan tool indicated a problem on one cylinder and it was actually on the opposite bank. Also, you could have an injector laying down.

 

[Marquezvtcobra]

About a month ago had car dynoed an it had a small " blip " on dyno ...my tuner said maybe plugs or coil ..it was a small slight hesitation ...

So tonight I pulled the old plugs TR7s and installed TR6s (place I bought them from said the cobra calls for TR6s)

I installed them tonight and now getting a misfire on #8 so I swapped coils with another cylinder to see if problem went to that cylinder and it did not stayed on 8 ...I even put one of the old tr7s in to see if problem went away same thing ...car runs like shit under boost

I ran a snap on scanner on the car driving it around and watching the scanner out for a ride #8 was showing -39 on the graph....

So I'm lost here on where to go ...

I have the exact same problem, let me know if you find the solution bro! :idea:

 

[BUNKY]

I would say 28-30 on the Tr6's but leave it up to your tuner.
I dont think its your plugs like others noted.

 

[CompO_Eric]

Id gap to 28 and switch coils around sounds like one took a dump

^this. My car was breaking up under boost due gapping...went to .030 on TR6s and it's fine now.

 

[KLLR SNK]

Might want to try TR6ix plugs at .032