[jester1]

I have 7/16" dimple rods with aftermarket bolt. The bolts do not have a company stamp/logo. How do I know what to torque them too? The have been resized already. IF I buy new bolts I have to resize them again correct? Or should I torque them to a standard range and check the bore of the big end?
thanks

 

[Tom Mobley]

Do you have access to a rod bolt stretch gauge? or willing to but one? You can see them at Summit or any of the other ususal vendors. might be cheaper than going through the whole deal again. Or, you could just torque to some reasonable value for 7/16 bolts and always wonder. the deal is, the bolts need to be stretched or preloaded a certain amount or they might loosen up. They can't be stretched too much or they will be in a fatigued state, might break.

Have you had a cap off? You could visually see if they're ARP waveloc or ground shank.

 

[jester1]

They are not waveloc bolts, just the common knurled shank. No markings on the head. Has the dimples for the stretch gauge.
Definatly willing to by a gauge. Woundering if I can by the holder by its self and use my snap on gauge?

 

[Tom Mobley]

if you have a "standard" dial indicator it might fit in the tool, but I don't recall seeing any for sale that way.

 

[Doug F.]

YOu would still need to know the stretch for THAT bolt. I'd rather guess on torque than stretch. But I don't guess.

 

[Schurkey]

The problem is that it's too late to be trying to address torque vs. stretch, or even stretch or torque values.

You need to tighten the bolts to the same point the machine shop did when they re-sized the rods. And THEN you need to hope that the machine shop torqued them the proper amount! Since the machine shop most likely installed the bolts, they--hopefully--paid attention to the instruction sheet that was packaged with them.

Is there any way to contact the machine shop that did the work?

The last-ditch method would be to take your best guess at torque values, and then measure the bearing bore to assure it's round.

By the way, rod bolt stretch gauges are now being imported from Communist China--which means you need to verify the accuracy and repeatability of the tool you contemplate buying. (all the ones I've seen come with the dial indicator) What good is a stretch gauge using a dial indicator that only reads to the thousanth, and has a crappy weak spring?

 

[jester1]

The problem is that it's too late to be trying to address torque vs. stretch, or even stretch or torque values.

You need to tighten the bolts to the same point the machine shop did when they re-sized the rods. And THEN you need to hope that the machine shop torqued them the proper amount! Since the machine shop most likely installed the bolts, they--hopefully--paid attention to the instruction sheet that was packaged with them.

Is there any way to contact the machine shop that did the work?

The last-ditch method would be to take your best guess at torque values, and then measure the bearing bore to assure it's round.

By the way, rod bolt stretch gauges are now being imported from Communist China--which means you need to verify the accuracy and repeatability of the tool you contemplate buying. (all the ones I've seen come with the dial indicator) What good is a stretch gauge using a dial indicator that only reads to the thousanth, and has a crappy weak spring?

Thats why i didnt buy one yet. As for the engine builder, no longer in this socalled realm:boring: .