con rod bolt quality

[Grumpyoldmen]

How often do you use new con rod bolts in your race engine?

[Lotus-e-Clan]

I've not changed mine in 3 rebuilds . (touches wood)

[ImpManiac]

Capscrews should be changed every rebuild, if they are ordinary, tensile bolts. I have ARP bolts in mine - the larger ones. They can be reused over and over, or so the sales person said! It's only a 930 but it's built to boogie!

IM

[Grumpyoldmen]

I thought this was very importante. At least in a fullrace engine. A matter of a rod through the block.....??
That is very triste.....molto triste

Kristian J

[Lotus-e-Clan]

Like Paul says go for ARP bolts and you can reuse.

Rods can let go if the bolts are poor quality but usually there are co-factors involved...careless torque down procedure, oil starvation, oil degradation, crankpin anomallies etc.

[KiwiHusky]

Like Paul says go for ARP bolts and you can reuse.

Rods can let go if the bolts are poor quality but usually there are co-factors involved...careless torque down procedure, oil starvation, oil degradation, crankpin anomallies etc.

Dead right. The pistons would give up the ghost well before the ARP bolts. Other factors in rods letting go would be over-revving and very importantly poor handling/storage of the rods while out of the engine, particularly whenever they are out of your sight, for example when they go for balancing or machining. Small nicks or dents caused by poor handling or storage can set up "stress raisers" which ultimately will lead to fatigue cracking if the engine is worked hard. Believe me- I've seen the results of this in other peoples engines for myself because I work in the Non-destructive testing department at Air New Zealand.

Cheers, Simon.

[Grumpyoldmen]

Are the con rods from the early engines (-63) the same as the later (-70)?

I have a set of con rods with good pistons (+ 0.020) that I was going to deliver to the dustbin.
(Then I hesitated for a moment, got back to my senses, never throw anything away etc.)

Kristian J