I need exhaust manifold to head bolt torque specs. I have the Acura factory manual for the 1998 Integra. On my ITR B18C5 there are bolts and studs for the manifolds. The manual on page 6-60 shows exhaust to head manifold bolts and studs with nuts (7 bolts and 2 studs), but lists only torque specs for the nuts at 23 ft-lbs. There is no number shown for the bolts. A similar figure on page 6-79 also does not give any bolt torque specs. 23 ft-lbs seems quite high to use for an 8 mm dia. bolt, as most are rated at about 16-17 ft-lbs for other uses in the manual.The intake manifold figure shows nuts at 18 ft-lbs and bolts at 18 ft-lbs (25 N-m). Figure on page 9-4 shows intake manifold studs and nuts at 17 ft-lbs (23 N-m), and figures on pages 9-5 and 9-6 also do not show exhaust manifold bolt torque, only nuts on studs at 23 ft-lbs.

What torque should to exhaust manifold bolts be tightened to? Does the manual show the value anywhere I missed? I am thinking that 23 ft-lbs is almost 50% higher than 16-17 ft-lbs typically given for 8 mm bolts, so it might be too high to use for the exhaust manifold bolts.

I road race my car so reliability under high stress and load is a concern, and I don't want to damage head threads over time with all the heat and vibration.

 

19ftlbs always works for me....