addballer696

what size and grade, ect. of bolts should I use to bolt headers to a 350.

burners

3/8-16x3/4 long. Any parts store will have them. Trans-Dapt or Mr. Gasket are the most common brands carried.
http://store.summitracing.com/partde...5&autoview=sku
http://store.summitracing.com/partde...1&autoview=sku
http://store.summitracing.com/partde...1&autoview=sku

addballer696

I gotta pick these up today at a hardware store because tonight I'll be putting on sidepipes. You think 3/4 is big enough or should I go with 1 inch?

Scott Marzahl

3/4" and make sure they are grade 8 minimum or they will break from heat fatigue.

AimHigh

Do it correctly now or you'll be paying for it later up under the hood....

7T1vette

I don't think 3/4" bolts will "get it". The outer 4 bolts are 2" long; the middle 2 bolts are 2-3/4". All are Grade 8 bolts. Put a bit of anti-seize compound on the threads so you can remove them 5 years from now.

Rolling Thunder

You may be right if he is installing cast exhaust manifold like original, but he said headers. All bolts should be the same length, 3/4".

Dustup7T2

Be sure to retighten after a few heat-cold cycles. Header bolts tend to loosen up sooner than you'd hoped and it'll save burning through the header gasket and creating another problem.

Suggestion for the anti-seize is experience & knowledge speaking, even on iron heads and especially on aluminum. Cheap insurance.