That looks like casting flash from when the parts were made/casted. Most likely those marks are just cosmetic from what I'm seeing in the pics.
09 BMW 335i E92 Twin turbo
89 Macrocab 4g63 Turbo swapped & Bagged: Build Thread
Make absolutely sure they ARE cracks, and not from when the aluminum was cast. A magnifying glass will help you determine this, also see if the "crack" cintinues on the opposite side. They might not be cracks at all.
They are casting flash. If cracks they would go right to where they would of started and that would be that hole where the bolt is. If you can't see them there then it's nothing to worry about. Mine has same thing and in more places.
1986 Mitsubishi Mighty Max ("Mitsy") Repair-Renew-Rebuild-Replace Thread
"My 1st Gen Japanese Vehicles"
1986 Mitsubishi Mighty Max ("Mitsy"-Purchased '87)
1989 Toyota MR2 GT (Purchased '08)
1974 Toyota Celica GT (Purchased '76 - Sold '12)
"1st American Car - 9th Gen"
1985 5.0 302 Ford Thunderbird (Purchased '14) - "Restoration"
many thanks everyone! i wasn't looking forward to scratching around in junkyards for these.
Got the head back from the shop already. The guy was able to remove the stud without damaging the threads so no helicoil.
They pressure tested it, vacuum tested it and inspected it. they said it's flat, straight and normal!
waiting on the gasket and bolts and exhaust manifold studs from Mitsubishi. should be here on wed ...