27psi race gas tune on stock headbolts question.
#16
Just some food for thought. When you have some detonation due to increased cylinder pressure, would you rather blow a head gasket or possibly break the rod bolts on your cylinder rods through your block. Head studs are not necessary with the factory turbo. You do not generate enough cylinder pressure. Detonation increases cylinder pressure to extremes. The weakest part will give. If you run factory studs and head gasket, you can replace them. With head studs, you can break a rod bolt and lead to catastrophic engine failure.
#18
#19
I agree with others on here it really boils down to the tune on your car that matters the most. I know someone who spikes about 30 psi or so and holds about 26-27 psi at redline and they have no issues. Now granted he is tuned by the great Jestr and no probelms. So I believe if your tuned on the money then all and in all your good to go.
#22
Just some food for thought. When you have some detonation due to increased cylinder pressure, would you rather blow a head gasket or possibly break the rod bolts on your cylinder rods through your block. Head studs are not necessary with the factory turbo. You do not generate enough cylinder pressure. Detonation increases cylinder pressure to extremes. The weakest part will give. If you run factory studs and head gasket, you can replace them. With head studs, you can break a rod bolt and lead to catastrophic engine failure.
Its always the weakest link in the chain, and if you strenghten the cheap links the the more expensive links are next to go. like if your clutch is strong enough the next weakest link is a diff or a gearbox...
.
#23
Cyl pressures and temps at stock boost levels with several counts of knock are much greater than say, 33 psi of boost with no detonation. It's just that high boost demands reasonable tuning and cannot be octane limited.
#24
Rod bolts dont become weak link during detonation. Rod bolts strength is tested by RPM. It is only a high centrifugal force that tries to stretch a rod bolt. During detonation the piston is at or near TDC. There is no cetrifugal force trying to stretch the rod bolts . The rod is being forced toward the crank. The rod bolt has an easy job of just holding cap on at that point. The piston and rod is straight up at that point. The high pressure cant turn the crank because it is straight up. It cant compress the rod. The cylinder head lifts up. Thats the weakest link. Installing studs will keep the head on better, but that only increases stress on the pistons by having less of a pressure release. Blowing head gaskets is not a bad thing. Its a good thing. If your pistons breaks instead your bottom end is toast. And even worse sometimes the head gets hit as well.
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