Torque Specs (Header Install)

[M1ck3y]

Installing headers soon and hoping someone can confirm these torque specs for me.

 

I have a haynes repair manual that says exhaust manifold bolts are 20 ft-lbs with new heads, or 17 ft-lbs with old heads. But it also says 17 ft-lbs with existing manifold, or 20 ft-lbs with new exhaust manifolds. I'm gonna say 20 ft-lbs is the correct one but everything online says 17. Says exhaust flange bolts are 20-25 ft-lbs. Transmission mount bolts 40 ft-lbs, but its confusing because there's a number of different transmission mount bolts. oxygen sensor 31 ft-lbs.

 

It also provides numbers for the steering column, but its confusing because of the multiple connection points with different torque specs. No numbers for the transmission cross member bolts to chassis (tight as you can get em?)

 

Not sure if I should be using anti seize either. On one hand yes for of ease of removal, on the other hand no because you'll end up over torquing the bolt...

Edited July 19, 2020 by M1ck3y

[CamGTP]

In all my years of working on cars I have never once torqued any of those bolts.

 

The heads are aluminum so the 15-20 ft lbs sounds about right. I just snug them up real good and call it fine.

 

I use my impact with a couple braps for trans mount nuts and the cross member bolts.

[M1ck3y]

21 hours ago, CamGTP said:

In all my years of working on cars I have never once torqued any of those bolts.

 

The heads are aluminum so the 15-20 ft lbs sounds about right. I just snug them up real good and call it fine.

 

I use my impact with a couple braps for trans mount nuts and the cross member bolts.

Thanks, appreciate it. You ever use anti-seize on 02's or header bolts?

[CamGTP]

I use it on the o2 sensor threads, most new sensors always come with a tiny packet for it too.

 

The header bolts themselves, no I don't use it there. I'm sure I could and see no issue with a tiny dab. Just don't go hog wild and cover the whole dang bolt with it. As some will say, a dab will do ya.

[davester]

I go for properly torquing down the exhaust manifold bolts, to minimize the chance of them breaking off (which they do for GMT800's at least)...