What bolts to use for headers?

What bolts to use for headers?

Most headers with 1/4-inch or 5/16-inch thick flanges will use bolts with a 3/4-inch UHL, while 3/8-inch thick flanges normally require bolts with a 1-inch UHL.

Can you use lock washers on header bolts?

They will work. But you need to be diligent about retorquing them a couple of times. Have a few extra around in case you lose one. Split lock washers only work when the bolt gets loose; they don’t work to keep the bolt tight.

Can I use Grade 8 bolts for headers?

Common practice is to replace the exhaust manifold bolts on ’94 – ’96 cars with Grade 8 hardware. They are hardened and will carry the highest tensile load, which seems to help them withstand the heat cycles the bolts are exposed to.

Can you use regular bolts for exhaust flange?

The usual options of exhaust flanges are the 3 bolt or 2 bolt types. Usually, m10 with the 2 bolt option is helpful, and an m8 bolt for the 3 bolt. The recommended grade of bolts is 8.8 tensile or higher so that you can tighten them without stretching or breaking the bolts.

How hot do header bolts get?

The exhaust can reach 1,000 – 1,200 degrees under a heavy load and even higher on integrated turbochargers and at high throttle.

Should I use anti seize on header bolts?

Anti seize is a good idea on header bolts in general, in my experience. Even steel in steel they tend to freeze up over time (if they don’t fall out, as they did to you). The advice to use some type of lock is also a good one.

Should exhaust bolts be Grade 8?

What grade are intake manifold bolts?

Grade 5 is fine for the intake, install washers under the bolt heads to get a better torque & to avoid tearing up the manifold. 30-35 lbs.

Can you use stainless steel bolts on exhaust?

SS bolts on an exhaust are a good idea – they will last significantly longer than standard bolts. They’re relatively unstressed. It’s a good idea to put some grease or oil on the threads to prevent galling as you tighten the bolts down as SS is a little softer.