Gonna revisit this L19 bolt torque gig again. I spoke with my shop and Callie rods. Callies said it was fine to torque to 92lbft and forget. My shop suggested measuring stretch, so i bought another stretch gauge. I will do this one more time and if i get the same results as last, it will be the last time i measure rod bolt stretch.

Here's what i bought.

I use this gauge. You have to wiggle it around a little to find your number. I measured a few rod bolt lengths and made a standard with drilled ends that mimic the bolt divets. This standard is marked top/bottom. Set the gauge to zero on the standard. Measure all the bolts 1st. Then you will know how they compare. Some will be longer, some shorter. Add you stretch figure to the measured numbers. Write all the measurements down keeping track of each bolts rod location in or out. So for example; say rod #1 inner bolt measures + .0005 and the outer is -.0006 vs the std. Lets say the spec is .0060-.0064. Now when you measure after stretching the inner should measure .0069-.0073 The outer should be .0054-.0058, This way you don't zero the gauge everytime. You can go back to your standard at anytime to check zero.
Doug

Thanks for that info. Callies suggest to torque bolt to 20lbft, zero the gauge. Then torque to full spec and measure. Not sure of the stretch at 20lbft.

Measure it and let us know

The locator on the gauge is fatter possibly fitting the head of the bolt better and giving better accuracy in the reading.

Been working on this a couple hrs now. The new arp gauge works real nice with repeatability within .0005. Sometimes the gauge will not always return to dead 0. No big deal, close enough for me. I was measuring .007-.0085 stretch with 92lbft. I backed the wrench to 90lbft and still got .007 stretch range. Backed it down to 80lbft and now between .0055 and .0065 stretch. I have a torque wrench checker and wrench seems very accurate . Both wrenches measure same readings. I have an old craftsman wrench and a newer Eastwood wrench. I will record and post some numbers later.

Not sure I quite understand your standard zero method. I just zero gauge once before I start. Measure bolts loose, torque both bolts and remeasure for stretch. Go to next rod.

I think the main idea is to have a repeatable 'reference point' (that being the fabricated standard) that you can always go back to. This takes out the +/- that might be introduced by the gauge/fixture as you are actively measuring the rod bolts. Basically, think of the inner workings of the gauge, or the potential movement of the components. So while resetting the gauge to 0 (zero) each time works for actual measurements, it does not provide you with the SAME starting point for EACH bolt...whereas the standard would, and it would remain that same for the remainder of time you needed to reference it (at least that's my interpretation of the procedure dvw uses.

Ok, i understand. If any issues were to arise with the engine and needed a rebuild i would just buy new rods. I would never reuse these rods. Its now looking like 75lbft of torque on the bolts keeps the stretch in spec of .005-.006.

I lube mine up and installed them to finger tight and then back them out around 1/8 turn so the bolts have no preload before I start stretching them. I zero the gauge on every bolt and I do see some small variance (maybe .0007 max in the lengths hence zeroing the Pro Form stretch gauge for each bolt.
I try to split the lengths to try and get them stretch to the middle of the short and long lengths, IE .0057 to .0062 I shoot for .0060
I have swap bolts around from rods to other rods in the same set after measuring them to try and get them matched up to have the same or close to the same lengths on all the rods
I guess you could take all the bolts out and measure them and then install them in the rods to get the lengths close together on each rod Maybe that is being more anal than needed. Your choice

I did rezero the gauge for each pair of rod bolts. Fully lubed up and loose i get a free length measure, then torque both bolts to 30lbft, then to full at 75# and remeasure for stretch. They were all between .0055 and .006, most being .006. Makes me a bit nervous knowing Callies suggested 92# and me finding 75# to get their stretch spec. Gonna have to learn to fully trust my measuring tools.

Final numbers:

Looks like you did good to me

Thanks cab. It just bothers me the spec was 92lbft to arrive at the stretch spec and i got there with 75lbft. I might give Callie another call about this. Thanks again guys.

I had one ARP 2000 Molnar rod bolt stretch to .0083 at 55 Ft. lbs. I suspect that bolt didn't get the correct heat treat I still have it
I decided to start at 40 Ft. Lbs. on all of his rods after that

I thought Molnar wanted his rod bolts torqued to yield? I have Molnar rods with his arp2000 bolts in my 511. I used his angle torqueing method, so i dont know the stretch on any of them.

May want to check back with him. I don't think he would advocate "torque to yield".

What is a torque-to-yield bolt? It is a one-time-use fastener that is designed to stretch during the torquing process (installation). Because of this stretching, the integrity of the bolt is compromised. These bolts cannot and should not be reused due to the stress caused to the bolt during its first installation.

Molnar supplies both stretch length and a low torque then torque angle spec.
Doug

The Molnar method is 30lbft then 44* i think. It is a specified degree for sure. According to him, you do it that way and you dont need to measure stretch with his arp2000 bolts.