Alright...so I thought I'd try to "elevate" my game (LOL, some will agree, some will ridicule, for me it was worth a lesson learned to do so) and decided to take the connecting rod bolt stretch approach this time around.

So here is the thing, I have Eagle H-beam rods which use their ARP 2000 bolts (supposed to be a Eagle spec bolt). I got myself a nice rod bolt stretch gauge, along with a nice 0.0005" Mitutoyo digital dial indicator. Even picked up a connecting rod vise. So far so good.

The free length measured out just fine, no problem, I can spin the bolt while mounted in the gauge and the indicator shows no fluctuation. My dial indicator uses a round shaped tip.

OK, so I toss the rod into my connecting rod vise, tighten and spot-check. The Eagle spec is 75 ft-lbs for a total stretch of 0.0064-8". Now here is the source of frustration: no matter how I hold the gauge with the indicator in it, no matter if I actualy remove the whole rod from the vise and measure that way, the readings on my indicator vary by more than 0.020"...so yeah, it's all over the freaking place!!! It's like I can't find the proper 'center' fit against the rod bolt.

I have a small assortment of indicator tips...you know, round, flat, pointed (cone), etc. So I tried the cone tip thinking that maybe my rounded one was moving around on me too much (which it seems like it was). Still, readings are no better!

No way was I expecting this to be so much of a PITA...it should be much simpler, so what am I missing here? Technique maybe??? Yeah, it's my first time trying this, but holy smokes...one shouldn't need a PhD. to pull this off...right? LOL

Help me out here...what have you guys used as far as setups go, and what do I need to watch out for in order to make my results repeatable?

I had same results as you. Measurements were all over the place. I had Molnar rods with same bolts. I just use Molnar's direction of torque to yield. Torque to 30# then clock bolt 60* if i remember right. Had great results. I think with the Hemi i will just torque the L19's to 95# spec and be done with it.

I got one of the cheap stretch gauges from Summit, and I just lift up on it and twist the gauge. If the needle moves a little, the longest measurement should be the length of the bolt. I find that most rod bolts, about 5 more foot lbs than the spec, puts the stretch right about on the money. With a little practice, I get good results.

I don't rely on the spring pressure of the dial indicator to read rod bolt stretch. Holding the frame of the stretch gauge with the pointy anvil firmly on one end of the bolt, I put the point of the dial indicator on the other end of the bolt and gently press the other end of the dial indicator towards the bolt as I move it around to make sure it's centered and get the lowest reading. So I'm pinching the bolt between the anvil of the stretch gauge and the dial indicator point In my experience that's the best way to get repeatability. Also I don't use 0005" measuring tools for this stuff. I always get the 0001". That makes it way easier, with the tight tolerances on rod bolt stretch. Same thing for my dial board gauge that I use on the big end of the rod, and the cylinder bores, etc. Edit: I guess my memory failed me. I just looked up a picture, and my indicator on this tool is .001"

I took a spring from an ink pen and and small washer I had for rivets as rest on and that put extra tension on the dial indicator plunger so it wasn't all over the place.

You may know this already... Make sure you record all of your torque figures in accordance to the stretch on each bolt... I could save you a ton of time in the future if for some unfortunate reason you would have to break the rods down.
example 79'lbs = .0049 stretch.

I never knew it was this hard or id of never started using the stretch method.

What brand gauge did you buy?

The stretch method is bay far the best as we see even pics on here of folks using tq wrenches from $13 to $350.

ARP 2000 are dummy proof bolts for us and the L19 are idiot proof.

There is some great info on I believe speed talk from some really in the know of how far off you can have the 2000 series and the L19 bolts and they will still work perfectly. The actual specs of what it takes to hurt a arp2000 and then the 19 is pretty substantial. Far more then we will ever put them through. Other things will fail first.

Keep an eye on the entry level eagle arps and they are still a 600hp 7500 rpm bolt that wont fail.

If you get used to the type of bolt you use you learn them. You can tell when a bolt is past its service life when it simply tq-s different then the norm.

Just take a break, look on you tube far a few vids and one day you will be able to set the stretch with your gauge and a breaker bar and a socket.

I dont think my arp gauge years ago even came with instructions. Your rods came with instructions and a area to keep stretch numbers, or they used to.

Straight from arp.

I didnt view this fully.

It would blow you away how easily and quickly I can do it, id explain here but many would give me a funny look, but never ever a bad rod bolt or even a bad rod bearing during inspection.

A decent one.

Its funny he uses two vs just remembering the value and adding or subtracting.

One last tip.... dont monkey around too much running them through the cycles or you will end up buying another set of bolts.

I think my rod bolt stretch gauge and tool are Pro Form, it works great
I bought it from Comp Cams 10 to 15 yrs ago, the dial indicator measures in .0001 increments. I set it at zero on each bolt and then torque the bolts, I sneak up on what the rod makers suggests on torque and find the middle of the stretch, if I can. In other words if they want from .0059 to .0064 I shot for .0061 to .0063. If they suggest 65 Ft. Lbs. I start at 50 or 55 Ft lbs. and go up in 5 lbs. increments
I do see differences in the rod bolt lengths (.00010 to .00030) as well as what torque is needed to get them to stretch to the length I'm shooting for, even on the same rod
I guess it might be faster to remove all the bolts and wash the rust stopper off of them and then premeasure the lengths and then try to match them up on each rod

My rod bolt stretch gauge I have came with a special/modified dial gauge that is high tension/pressure. Are you using one of those?

I started with the indicator gauge method. Gave it up and took the spindle out of a micrometer and ground it to a small radius tip. Perfect, same readings every time. I did the stretch method on one engine about 12 years ago and that engine is still running strong. Have built several engines since then using torque method. Only one gave up the ghost and it was an oiling problem. So decided just torqueing has worked for years. SO why change just because some jackass with a college degree had a wild hair?

I appreciate all the responses you guys.

Yes, I did educate myself as to the tools and various ways of executing this process, but extra materials are always welcome, so "Thank You" Mr PotatoHead!

The bolts have had their free lengths all measured and recorded. Each rod set it flagged as either IN/OUT, meaning with the rod installed on the crank, is the bolt closest to the center of the block (IN), or is it facing OUT. My process so far was to tighted the bolt in: 20-50-60-65-70-75 steps and measure the stretch each time. I figured I would start off with this and as I established the "feel" for how these bolts respond, I would mostly likely just dwindle this down to a 60-65-70-75 stepping afterwards.

I have several dial indicators available, including a 0.0001" as well, which actualy does provide the most stable measurements. My only problem with that one is the fact that the Amazon ad mentioned nothing about it being a 8mm stem and well given that my tools which are all meant for 3/8" I was hesitant to put that one to use. Anyways, last night I tossed it in, it gets locked into place by the gauge set-screw anyways, so no movement is possible and the center of it's stem will be off-center by just a tad. I thought it would be worth it just to see how it compares.

The results are more stable for sure, certainly the precision makes it much easier to pin-point the center of the bolt. It was late, my eyes were tired, I was grumpy and still frustrated, so I wrapped it up. More 'trial and error' today...lol!

Now, most of the time a picture's worth a thousand words, right? So take a peek at a few pics of what I have here.

Ultimately it would seem to me that for this specific measurement a dial indicator with a slightly higher measuring force/pressure is needed. That way the tip stays more firmly planted in either end of the bolt you chose to place the indicator on. I think this is what KD800X is talking about in his post and the reason why Hemi_Joel is relying on a slightly different way of positioning things. I will have to try that.

Thanks again everyone, now off I go back to the "lab" for more experimentation!

Nope, most certainly NOT!

I think that is part of my problem...the tension on the dial indicator plunger is too light and that causes the reading to vary as I attempt to hold the gauge in place to get a reading.

I will try to take the Amazon gauge apart this evening to see if this is something I can change.

The right spring and a small flat washer under the tip should do it.

I just went through a set of rods wanting. .006 to ..0064 . after a couple of rods I found that well lubed 7/16 x 1.60 ARP 2000 bolts needed 87 ft lbs on my old Craftsman beam type torque wrench to be in range, usually .0062. I have click type wrenchs, but that old cheap beam type is as reliable as a hammer.

Dip360 you did adjust the gauge for your length bolt I got to ask? And I like to set it so the gauge is bout 1/2 through its sweep for good tension and then zero it. The arp unit works flawless from the box with the tiny adjustment.

Sure did, great question to ask though.

Here is specifically what I do:
1) measure the free length of each bolt with my micrometer
- the challenge here is that I do not have a point tip on the micrometer and so the length is measured from the top of the head down to the end of the bolt, ideally I would rather match to how the stretch gauge is measuring (the pitfalls of being a DIY guy with a limitted precision toolset)

2) I zero the dial indicator for each bolt when it's not installed in the rod

3) I then torque the bolt and spot-check as per the torque steps I highlighted above
- I tighten both bolts on the rod, but only measure one, which means I repeat this step twice - once for each bolt

4) I then re-check the free length when the bolt it completely removed to see if it got stretched beyond it's capacity

I have my dial indicator about 3/4 through its sweep, leaving just enough to clear the bolt head. I was trying to get the higher spring tension at the top end of the sweep that way.

I have my dial indicator about 3/4 through its sweep, leaving just enough to clear the bolt head. I was trying to get the higher spring tension at the top end of the sweep that way.

What brand gauge did you buy?

My arp thats maybe 18 years old now holds the bolt so well I could toss the whole unit across the shop and not ditch the bolt.

I adjusted a bit too far for this pic.

Here is how I do it. I apply pressure with my thumb. It works fine and is consistent.