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header bolt question - options

marc

Full Member
Joined
Jan 7, 2007
Messages
154
Loc.
milwaukie,or.
are header bolts a special grade or can you use a standard bolt. should they be grade8. is it the head that makes them different. are stage-8's as good as they advertise. i'm using mustang shorty's. i'm getting close to start-up and could use your help. thanks much.


marc
 

broncnaz

Bronco Guru
Joined
May 22, 2003
Messages
24,341
I dont think grade 8's are needed or any better on a exhuast system. I would go with standard type bolts grade 3. My reasoning would be that the exhuast sees a lot of heat and things tend to rust if that bolt decides to rust itself into the head its easier to drill out a grade 3 than a grade 8 although the grade 8 might still come out with out breaking where a grade 3 may twist off. But really I've never had a single problem with the standard header bolts sold by Mr Gasket.
 

bjs254

New Member
Joined
Feb 7, 2008
Messages
19
Loc.
Newnan,GA
grade 8 should be ok, but most of all use a copper anti-sieze. I also used asbestos header wrap to keep everything cool under the hood and saftied the bolts, good luck
 

okorangebrnco

Bronco Guru
Joined
Nov 25, 2004
Messages
1,650
Stage 8's are great, but a pain if you need to take them off again. I just used standard bolts. I had a set of ARP's and they would back out, Atwoods grade 5 have worked the best yet
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,821
Best header bolts I have ever used. ARP big block chevy. Drilled for safety wire. Then wired them. Never retightend them and 2 years later they were still good.
 

wildbill

Old Bronco Guy
Joined
Jun 29, 2001
Messages
6,885
:p :p :p The ones I use are allen head with a nylon insert in the thread. They dont come lose put the last set of headers on in 86 and havent had to touch them since. What you do is torque then down run till hot retorque let cool and do it once more then you are done I use paper gaskits get them wet before putting on and you will be good to go good luck.%) %) %) Bill :p %) ;D
 

Buldozer

Bronco Virtuoso
Joined
Oct 17, 2007
Messages
3,065
Loc.
God's Country
Not sure about the grade, but the head is certainly what makes them different. I usually find only one or two places where a normal bolt would fit. If you have a small block Ford, you will certainly have difficulty using normal heads on many of the bolts because there is just not room for them. I always tighten them, heat them up and cool them down and tighten again. Also, I recommend matching the head ports with the gaskets and headers. I do this by putting the gaskets on the heads and trimming them to fit the ports where any gasket material may be blocking a small portion of the port, then take them off and put them on the headers and scribe the gasket pattern on the header (if it blocks part of gasket hole). Then use a die grinder to trim out the mating edge of the header if needed so the flow is uninterrupted from the head through the gasket into the header tube. This can really improve performance where significant there is significant mismatching .
 
OP
OP
marc

marc

Full Member
Joined
Jan 7, 2007
Messages
154
Loc.
milwaukie,or.
thanks guys, the brotherhood i've found here has been the most valuble source of information and freindship anywhere thanks again.:)

marc:cool:
 

Dave

Contributor
Bronco Guru
Joined
Aug 25, 2006
Messages
2,190
Best header bolts I have ever used. ARP big block chevy. Drilled for safety wire. Then wired them. Never retightend them and 2 years later they were still good.


Interesting! Seems like most of the chronic Explorer header cracks are due to loose bolts. Guess it's cheaper for Ford to replace headers than design a better bolt retainer.
 
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