Looking for some help on torque spec on an older Oliver rod for a SBC.
I have called Oliver numerous times. I get a generic message that no one is available and the mail box is full.
The bolt is a 7/16 thread, Under head length is 1.3" head bolt is 12 point 1/2"
Head of bolt is marked Oliver Std USA ARP 819.
If any one has any information on the correct torque, angle and or stretch it would be greatly appreciated.
I will call ARP next but they have never provided any information on anything that is made as a proprietary bolt for a manufacture

Oliver has a unique process for torquing their rod bolts that requires the use of a Snap-On TA360 (Or similar made tool). I've forgotten the exact process but it requires tightening the bolts to a pre-set number, then relaxing the nut, then tightening it a second time to a stretch number using the TA360.

You really need to contact Oliver about the process, someone at ARP may have the info, and with all due respect, call Oliver I think the bolt material may be proprietary, not the normal ARP material found in a catalogue.

Good luck:

Bob

quote:

Originally posted by RPROGAS:
Oliver has a unique process for torquing their rod bolts that requires the use of a Snap-On TA360 (Or similar made tool). I've forgotten the exact process but it requires tightening the bolts to a pre-set number, then relaxing the nut, then tightening it a second time to a stretch number using the TA360.

You really need to contact Oliver about the process, someone at ARP may have the info, and with all due respect, call Oliver I think the bolt material may be proprietary, not the normal ARP material found in a catalogue.

Good luck:

Bob

Thanks Bob
Yes Oliver uses the torque angle to check stretch.
Due to the bolt being Oliver proprietary ARP will not provide any information.
I thought of replacing the bolts but ARP does not have any bolt listed in their catalog that is 1.3" under head length.

Did you see this on their site.

https://oliverracingparts.com/...5/2023-BOLT-INST.pdf

2BKING

quote:

Originally posted by B KING:
Did you see this on their site.

https://oliverracingparts.com/...5/2023-BOLT-INST.pdf

2BKING

Mr. King, yes I have been all over that page.
The bolt I'm needing information on is only 1.3" under the bolt head long.
All of the Oliver and ARP bolts are minimum 1.5"

Well I received a reply back to my email to Oliver.
This is a very old rod that is not longer manufactured and the rod bolt is not available.
No information on the bolt and its torque.
Like I posted before I have not found a bolt that short that I could replace it with.
With that being said looking at all of the different stretch numbers I found that 75 Lbs with the moly lube netted me .005 stretch, which is the nominal amount called out for all of the various materials.
This engine will be 500 HP Max so I hope and pray that it will be sufficiant.
Thanks for all of your help and comments.

Oliver makes an excellent connecting rod, I've been to their manufacturing facility located in a small Industrial Park off Rt. 66 about a mile north east of Charlervoix, Michigan. The building maintains a constant temperature during all the machining processes so they have thermal control over the end product.

These folks make an excellent reliable product. Bruce, you are not going to hurt it with a 500hp engine.

Bob

Here is what AI provided, take it however you like...

The **819** stamping on the head indicates an early custom run ARP produced specifically for Oliver's standard (Std) 7/16" 8740 / ARP2000 series cap screws.

With performance rod bolts—especially older 7/16" fast-pitch cap screws—**bolt stretch is the gold standard**. Final torque numbers can fluctuate wildly based on thread condition and assembly lube, so target stretch first.

Fastener Specifications & Target Stretch

Thread Size:** 7/16"-20
Under Head Length (UHL):** ~1.3"–1.4"
Target Stretch:** **`.0053” to .0057”`**
Tightening Procedures

Method 1: Stretch Gauge (Recommended)

1. Thoroughly clean and dry the rod threads and bolt threads.
2. Apply high-pressure assembly lubricant (**ARP Ultra-Torque** or Oliver thread lube) directly to the threads and under the bolt head flange.
3. Seat the bolts by cycling them 2 to 3 times (torque down, loosen, re-lube). This burnishes the threads for accurate clamp load.
4. Measure and zero your stretch gauge on the relaxed (untorqued) bolt.
5. Tighten until you reach **.0053”–.0057”** of total stretch.

Method 2: Torque & Angle

If you do not have a stretch gauge, Oliver recommends a torque-plus-angle method to reach the target stretch accurately:

1. Initial Snug:30 ft-lbs
2. Final Angle:`+42° to 45°(Pull the angle in one continuous, smooth stroke—do not stop mid-pull).

Torque-Only Reference:** Using ARP Ultra-Torque lube, **30 ft-lbs + 42°–45°** typically yields approximately **`70 to 75 ft-lbs`** on a standard click-type torque wrench.

Crucial Tip:** If you pull the torque/angle method and check stretch, but come up short (e.g., only getting `.0048”`), **do not** just keep clicking the torque wrench in small steps. Back the bolt off completely, re-lube, reset your 30 ft-lb base torque, and add **2° of angle** to your final pull. "Chasing" stretch in small increments under load causes thread friction to lock up early, leading to false torque readings.

Method #1 using a ARP stretch gauge has been the most reliable process for me.

Anyone interested in a Snap-On TA 360?

Bob