1973 2.4L 911T Connecting rod bolt Torque spec.

[oris1391]

Looking for connecting rod bolt torque spec, I'm using factory bolts, I'm getting conflicting answers, is it 14ft and 90deg or 37-41flbs?

[Dmitry at Pelican Parts]

Grab a manual if you're able to. It'll have all the torque specs and wiring diagrams in there.


-Dmitry

[oris1391]

I have 2 manuals, a factory and Wayne's book, Im getting conflicting values, Wayne's book says 14ft and 90 deg and the factory say 37-41lbs?

[tharbert]

Bruce Anderson says 37-40.5 in his rebuild book (P126.) I believe Wayne says 15 ft-lbs then 90 degrees (don't have book handy...) Here's a pretty good discussion about both specifications. I can see where this is a crucial measurement but also note Peterfrans' anecdotal observation that he could find no reports of engine failures due to OEM rod bolt issues. I have to admit my crank is still in my closet along with all new OEM hardware. I haven't screwed up the courage to take this first step because of the very question you've asked here, Mr. Oris1391.

YouTube of Nick Fulljames assembling a 2.0 (?) crank.

Good luck!

[oris1391]

yes, there is quite a difference in torque between the 2 specs, I have a digital torque wrench and when torquing the bolts to 15 ft-lbs then 90 degrees my wrench displayed the torque at 56 ft-lbs, the rod clearance is also greatly affected, my clearance at 40 ft-lbs is 0.038 and at 15ft-lbs and degrees they were 0.030, most people use ARP hardware, so this is a non issue.

[Trackrash]

Bruce Anderson and the original factory manual specify 37 to 40 ft-lbs.

The spec listed in Wayne's book is for the newer (84 on ) motors. There is a note at the bottom of page 200 suggesting that the original spec can be used on older motors.