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MarkStang Header Bolt/Gasket Review

MarkStang

Member
The Gaskets are Percey's Seal 4 Good Lifetime Gaskets
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The Bolts are Percey's Split Lock. These are the 1 inch Stainless, Edelbrock heads easily except 1 inch bolts dirrectly with out anything under the bolt head, allowing a better hold depth.
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The aluminum Gasket has a flat side and a cupped side. The flat side goes on the outside to mate with the Header. The Percey's gasket appears to come as a set of 4 , however 2 are pressed together to form 1.
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Issues with a 12 point wrench were minimal. Three bolts were non accessible with the 12 point. This would be an issue for this particular Header and a die hard perfectionists would Balk at. I had no problem using Vise Grips, in fact these 12 points made it a breeze to tighten with them.
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Next is the Vise grip issue.Issues like these are good to review.3 bolts were tightened with a vise grip. Headers with an aluminum Gasket compress as the bolts are tightened. As the bolts are tightened and compressing the aluminum they create a loosening effect on the bolts in either direction next to them. This effect happens easily if attention is not given to even torquing. The point I wish to make here is that the Vise grips tighten very easily on the three I had to use them on and cause the Bolts next to them to become loose just like the wrenched ones.Removing the spark plug made the job a simple one with the grips.
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The following shows a gap prior to tightening and after.
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The end result is a tight clean look with gaskets that will not burn and can be used over and over. If Paper type gaskets are used with the Split lock bolts then adjustments are made easy with an Allen Wrench and a 12 point wrench. Some Headers may require creative tool uses. All in all attention was given to the confinement of doing the job in the engine compartment (mine is not in the car yet) so every thing I did was in consideration of fender issues. I has a Small Block and this alone makes my application very good.
 
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Snap-On makes an open end 12 pt wrench that can help get to bolts like that. Expensive damn thing though. However, I found it comes in handy for plenty of applications.
 
Nice write up. Do you think you will be able to get the engine back in with the headers on or will you have to take them off?
 
I've tried copper gaskets, aluminum gaskets, etc., etc. None of them work as good as the GOOD Felpro paper gaskets, IMHO. None of them are as cheap either.

Locking header bolts are a must, IMHO. Unless you like to tighten them once a month, anyway.
 
"68EFIvert" said:
Nice write up. Do you think you will be able to get the engine back in with the headers on or will you have to take them off?
I tried with them on and it is close but no way. I put them on for the right up and gave it a go.
 
Thanks for the update. I spent about 1 hour trying to get the back bolt on the #1 cyl on my headman headers two nights ago. That thing is so hard to get started. I forgot about using vice grips. In fact I have a set of Stage 8 locking header bolts that I am not using and elected to go with ARP bolts since I can't get a 12 pt wrench on many of the bolts. I wish I could find a 6 pt locking bolt with the allen head in the center.
 
One of the bolts had to be started while floating the headers with the bolt all the way in the whole, find the head and bring it to the block.
 
I've had excellent results with the Percy's aluminum gaskets. They've been on my windsor for about 30k miles and not a single leak. I've not had to retighten the bolts and my bolts are not locking either. Guess I'm just lucky :coo

This may be obvious to some, but for those that don't know the headers can be installed with the outer two bolts, then slide the gasket down between the header and the head, then install the rest of the bolts and tighten them up. That is the reason for the U-shape opening for bolts on the gasket.
 
"buening" said:
I've had excellent results with the Percy's aluminum gaskets. They've been on my windsor for about 30k miles and not a single leak. I've not had to retighten the bolts and my bolts are not locking either. Guess I'm just lucky :coo

Same here, I checked the header bolts because I was expecting them to loosen, thankfully they are all still snug as a bug (knock on wood).
 
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