Aluminum Intake for 351C 4V torque specs - different from cast intake?

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1973 Ford Mustang Mach 1 T5 Q-Code 4-Speed
Hi guys, 

as I want to install my refreshed Offenhauser (5964 - Offenhauser 360 Degree Single-Quad High-Rise) intake tomorrow there have been the question for the torque specs with the original bolts. Is it different than for the cast intakes or the same? I have forgotten about it, last I installed it is 6 years ago... 

Thanks for some advice! 

 
No difference in the toque specs. To reiterate, be sure to use the tightening sequence in the shop manual. There are two torque values, as the intake has two bolt sizes. 

 
@all: 

Thank you for the response! 

So I will take a look on my shop manual and do what they describe as I did 6 years ago. As I recall there are these two different torque values: 





5/16 in. Intake Manifold Bolts


21-25 ft.-lbs.




3/8 in. Intake Manifold Bolts


28-33 ft.-lbs.





But I will have a look on my shop manuals anyway. 

This time I will do the "China Walls" with RTV instead of the rubber or cork gaskets as I have had no luck with these between an aluminum intake and the block. 

Two more question about installation: 

- Original bolts torqued down with some engine oil in the threads or pure and dry? 

- Is it necessary to retorque the intake bolts when the engine once has warmed up after initial firing up or is it once torqued down, three times checked and ready? Hence with all completely installed again retorque wouldn't that easy as now... 

Thanks 

 
I use a LITTLE bit of engine oil on the threads and on the bottom of the bolt hex head. I also use hardened washers under the bolt head.

I torque the bolts per the manual or the intake manufacturer. Heat cycle it a few times and re-torque with the engine cold. Chuck

 
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