Header Bolt Question

[wrc3]

I am finally putting in my headers this week and my question is what do people use to fasten the bolts down? Any one use lock washers or anything like that?

B

 

[Bob Chadwick]

Take a look at this post.

 

[80convertible]

I've got stage 8 locking header bolts but my headers still leak. I've decided that only good quality headers are the right purchase. I have Dynomax ceramic coated headers. The problem is the o ring surface is not smooth. I would suggest checking this surface and sanding if it is not smooth. I hope you have better luck than me. On the other hand, they sure look and sound cool!

 

[wrc3]

thanks

I got the Jet Hot coated Hooker Headers. Someone suggested allen bolts with red loctite. What do you think?

 

[Bob Chadwick]

I've got stage 8 locking header bolts but my headers still leak.

What did you use for a gasket?

 

[80convertible]

I used a soft copper gasket.

 

[69autoXr]

I have DynoMax 1 5/8" primary tube headers. One good thing about the smaller primaries is that there is enough room next to the tubes to use lock washers on all of the bolts. I did this, and haven't had a loose header bolt or burned exhaust gasket in almost 5 years.

Chris

 

[The73vetteman]

I have allen bolts on my headers. They seem to hold OK.

 

[KenSny]

Red Loctite will not work at header temps.....

 

[Mako]

I used a soft copper gasket.

I have had excellent results on both my hotrods engines (a SBC and an LT1) with Earl's "Pressure Master" header gaskets with standard header bolts. They use a replaceable graphite insert as the seal.

I've had 0 header bolt loosening issues. The mouse has iron heads and the LT1 heads are of course aluminum. You can order them from JegMit etc...

CYa!
Mako

 

[Bob Chadwick]

The header bolts and gaskets are due in today. Pulled my AIM to see what the torque should be on these things and of course that page is cancelled and is missing this information.

Can someone tell me what the torque should be and in what order they should be tightened?

Thanks.

Bob

 

[JohnZ]

They were never in the A.I.M., as they were part of the engine as received at the assembly plant. They're 3/8"-16 bolts, torque should be 25-30 ft-lbs. If you don't use Stage 8 locking bolts or bolts with drilled heads and safety-wire them, they'll loosen and you'll get a leak and blow gaskets eventually.

Torque alone doesn't keep them tight; clamping force is what keeps them from loosening. The stock manifold bolts are much longer than header flange bolts, which allows the stock bolts to stretch slightly at torque, which maintains clamping force. Header bolts are too short to stretch at torque, so they don't retain clamping force through heat cycling, and loosen up unless they're mechanically prevented from loosening. Or, you can just tighten up all 16 of them once a week in order to avoid leaks and blown gaskets. The joy of headers.

 

[Bob Chadwick]

Thanks John. Always a good source of info even when you are the bearer of bad news.