VQ37 header install worth it?

I installed headers on my G37 But I got a misfire right after which happened probably because I didn't disconnect the battery. The installation applies the same to 370z's.

Oh and guys check out Lukas Lenner's channel it's awesome and very helpful. He helped me with a ton of tips while I worked on mine.
   / lukaslenner  


Music credit:


Track: Dark Heart - Crash Test Dummy [NCS Release]
Music provided by NoCopyrightSounds.
Watch:    • Dark Heart - Crash Test Dummy | Electronic...  
Free Download / Stream: http://ncs.io/CTD

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Track: Jim Yosef x ROY KNOX - Sun Goes Down [NCS Release]
Music provided by NoCopyrightSounds.
Watch:    • Jim Yosef x ROY KNOX - Sun Goes Down | Mel...  
Free Download / Stream: http://ncs.io/SunGoesDown

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Track: Aeden & Joellé - I Feel Crazy [NCS Release]
Music provided by NoCopyrightSounds.
Watch:    • Aeden & Joellé - I Feel Crazy | Future Hou...  
Free Download / Stream: http://ncs.io/IFeelCrazy

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Track: Dirty Palm - To The Back (feat. Purple Velvet Curtains)[NCS Release]
Music provided by NoCopyrightSounds.
Watch:    • Dirty Palm - To The Back (feat. Purple Vel...  
Free Download / Stream: http://ncs.io/ToTheBack

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Song
Nekozilla
Artist
Different Heaven
Licensed to YouTube by
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