This stainless steel exhaust manifold kit is for mounting stock manifolds to the heads on your Buick Nailhead 322-364-401-425 engine. The bolts and extra thick washers are 18-8 stainless steel and the bolts are 1 1/4 inches long. Please verify the fit to your engine before ordering. These bolts are not Grade 8 bolts.
If you have the exhaust manifolds that have 4 longer bolts at the Rear of the Manifold, let us know at the time of payment and we’ll send the 4 longer bolts that are required.