Not looking for fiction or fantasy opinions, but FACTS!! Can cylinder head nuts be re-used or does the Factory say to replace?? Can connecting rod bolts be re-used or does the Factory say to replace?? It is widely know that TTY(torque to yield) bolts and nuts HAVE to be replaced.......are the above TTY?? As far as I can see the WSM is not definitive...did I overlook this in my much reading??.....lol
I would replace them George and the studs also. This a highly tuned Ferrari engine we are talking about here. I always replace them when I rebuild any type of engine. Studs AND nuts that is.
Typically head studs (don't usually remove them unless there's a good reason) and nuts get re-used. Connecting rod bolts and nuts should be crack-tested.
Is that the go with Ferraris eh? There is not an issue with threads or studs stretching on them is there?
I've never seen anything regarding replacement. The WSM images are all with the studs in the block. Removing head studs from aluminum engine blocks can cause more problems than it solves so I try to avoid it when possible.
Ah, you are probably right there mate. I have never dealt with alloy blocks with studs, so it will probably pay not to touch them.
Agreed about removing studs from an alloy block. Can be a real problem. You should try removing a Alloy cylinder head when one or more studs just seize in them I have had to scrap a head (none Ferrari) from an engine because two btich studs was fused to the inside of the head. I had to get a hacksaw blade between the block and head with only about 3mm to work in. Two days later it came of God all this is bringing back bad memories, suddenly i feel sad and my ticks returned
I have had to do this in the long ago. What I did was cut the stud off about a half inch from the block and heliarc weld a "handle" to it. Immediately turn the handle while still hot and the studs turned right out easily. Trying to remove them cold is an invitation to disaster If they really are torque to yield then they should be replaced. The reason is that in “torque to yield” the material is stretched to its yield point then a bit further thus deforming the stud/bolt. As I remember it, the ultimate strength is reduced about 40 % by re-torquing one time, but my memory is not what it should be, anyway it was a significant reduction in strength. If the studs/bolts are reduced shank then they are most likely torque to yield. Rule number one in engine building is never reuse rod or flywheel bolts. I used to reuse head bolts/studs one time only. My logic was that rod or flywheel failure was catastrophic, while head bolt/stud failure was an easy fix.
