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Strengthrehab's Better Late Than Never Build Thread

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That first plug does not look good.
 

racer47

Still winning after 30+ years
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20+ Years
SE WI
That was on cylinder 8. 2nd plug was cylinder 6 (bad one)

Its not uncommon for broken pieces from one cylinder to go back up the intake and then into a different cylinder. That could explain the closed plug gap. But normally you see dimples on the piston tops and aluminum speckles on the plugs. I don't see either, except for the center of your borescope pic. I can't tell what that is directly in the light. But as you said, you need to pull the head and see whats going on. Good luck.
 
Gotta pull the head then order a new head, swap all springs, upgrade OPG, timing chains, tensioners and may upgrade to a ported 18 intake and stock 18 airbox.

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I've decided to do this myself unless something changes. My guy (rightfully so) would charge $1k just to swap the head. Ugh.

Plan going forward is:
1. Replace DS head (cheaper than valve job probably)
2. Swap new springs onto PS head
3. New OPG and crank gear
4. New timing chains, tensioners
5. Long tube headers.

I was going to upgrade to a standard or ported 2018 IM, but not entirely sure yet. I can pick one up for about 230 bucks.

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Got word that my engine issue wasnt as bad as possible and I kinda lucked out.

When the valve spring broke, the valve was apparently held tight by the retainer and didnt actually drop far enough to kiss a piston.

Now I just have to have a machine shop check out the valve to ensure it is straight, check the guide and install factory (gen2 and boss 302 spec) springs.

Darker holes are #8 (bent electrode) and other is #6 (broken valve spring)2e2d705af3481d4dade085bf6209c59f.jpg716cd869d8d718fdaa0e40743cc9e8ec.jpg9e499280b35edf47088fb7f3e5836cf0.jpg3a2aad6e524a02370cb69ce01fa86b50.jpg

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