Confirm 1989 911 Rod Bolt Torque procedure

[Dauner]

Hi everyone,

I think I have a couple of hours in to reading Pelican, Rennlist, etc. regarding proper procedure and values for installing my reconditioned factory Connecting Rods to my Crankshaft.

Notes:

• 1989 911 3.2 Engine
• Factory Connecting Rods reconditioned with new bushings and bearings
• Crankshaft polished and measured within specifications
• Porsche New Rod bolts and nuts.

Because this is such an important part of the assembly build, hoping someone can confirm this is the process to follow for my specific situation.

Process: (if something is wrong in my process, I can go back and edit the post)

1. Install original bolts and nuts on rods
2. DO NOT add any loctite, oil, lube of any sort on threads or face of nuts. My original nuts were standard Hex nuts
3. Place rod in bench vise with wood between rod and vise faces, only having the vise grab the main portion of the rod, not the Cap. I do not have a purpose built rod vise.
4. Torque nuts progressively to 14.7 foot pounds, alternating nuts as I go. Planning to start with 8 ftlbs, then 12 ftlbs, then 14.7 ftlbs. I will actually target 14 lbs as that is what Bentley states, but mathmatically 20 Nm is 14.7 ftlbs.
5. Torque an additional 90 degrees (one time only)
6. There is no factory bolt stretch specification for Porsche factory bolts, so not using that method
7. Remove Rod from Vise and measure/record Big End (BE) bore at 5 locations. (1 and 2) Either side of the seam, (3) 90 degrees from the seam, (4 and5) roughly 45 degrees, midway between the other measurements.
8. For measuring bores, I plan to use a bore measuring tool that expands out to the diameter with two points. the ends are slightly domed to account for curve of bore. Then measure the length of this bore gauge using a 4 place non-digital micrometer with resolution to 1/10,000ths. The total tolerance window is less than 1 thousandth inches, so need 0.0001 resolution
9. compare BE bore diameter to crankshaft Rod Journals to validate acceptable bearing gap using numbers published in Wayne's 3rd revision book.
10. place rod back in vice with wood protection and remove original factory bolts/nuts.
11. install rods on crankshaft using assembly lube following other general cleanliness and lube procedures in Wayne's book.
12. place small amount of red loctite and spread on threads. NEEDS TO BE CONFIRMED BY SOMEONE PLEASE
13. New Porsche Nuts are triple square. I do not know what size yet. New porsche rod bolts are 12.9 grade.
14. New 12.9 grade rod bolts are progressively torqued in steps to a final torque of 20 Nm, which is 14.7 foot pounds. NEEDS TO BE CONFIRMED BY SOMEONE PLEASE
15. Torque an additional 90 degrees +/- 2 degrees.
16. Check for rate at which rods fall under gravity as compared to each other. should fall under their own weight

Honestly, I feel pretty bad posting this as this has been beaten to death, but as a first timer, with so many threads and corrections, its still confusing. I'm looking at dates of posts, and trying to discern which are the latest posts. I have BIG questions on the loctite on both the original bolts for measuring purposes (I wasn't planning on using it). Same question on final assembly. Loctite, no Loctite, non-synthetic oil or dry. If use loctite or non-synthetic oil on threads and mating surfaces, still use 20 Nm and additional 90 degrees? One person did ask about if anything changed in the 1987-89 cars, but the only response was 1988 was the same. I don't know if my 1989 (which was a transition year) is still the same specs. Same engine so I would expect everything the same.

Sorry for the long post. First time I'm truly nervous about what I'm doing in this entire process...