Grade 8 or Torque-to-yield for intake manifold and plenum?
#12
#14
#16
This is an awesome description of bolt tightening theory: http://www.enginebuildermag.com/Arti...uetoangle.aspx
#18
I use stainless. Every time I took the manifold off with either grade 5 or the stock bolts the things were corroded as all get out. I'll wager that blow by gases and electrolysis work a double whammy on them.
There are several charts on the Web with torque values for various bolts. IMO, the best bolt to use would be the one that gets as close to 144 in/lbs as possible at the correct torque yield.
Stainless is close. Monel bolts would be best, but its damn pricey for the corrosion resistance characteristics.
Be careful what you buy at the local hardware store. If you buy a 2.25" grade 5, because you are trying to match the length of the factory bolt, you might find that they run out of thread before you get adequate clamping force on the gasket. On the other hand, the 2" bolts only grab by a few threads. A 2.25" all thread bolt would be best.
There are several charts on the Web with torque values for various bolts. IMO, the best bolt to use would be the one that gets as close to 144 in/lbs as possible at the correct torque yield.
Stainless is close. Monel bolts would be best, but its damn pricey for the corrosion resistance characteristics.
Be careful what you buy at the local hardware store. If you buy a 2.25" grade 5, because you are trying to match the length of the factory bolt, you might find that they run out of thread before you get adequate clamping force on the gasket. On the other hand, the 2" bolts only grab by a few threads. A 2.25" all thread bolt would be best.
Last edited by aim4squirrels; 10-26-2011 at 10:32 PM.
#20