I need to replace my header gaskets and bolts on my stock '70 350/300hp and have run into a few issues I could use some assitance on:
1. Which gaskets should I use? - I have no idea what type of headers are on the car (installed by previous owner). Headers are old an ugly and used to be white graemlins/sad.gif but they'll have to do for now.
2. What is the best way to get the old bolts off? I can't fit a socket head completely over the bolts because the pipes are too close to the bolt head.
3. Headers are welded directly to the pipes, will this be an issue?

Thanks in advance!

I use an open ended wrench to tighen and loosen my bolts. The pipes being welded will not be an issue as they headers should still have enough play in them. Get the best gasket you can afford, and install it. Drive the car for about 30 mins or so to get up to operating temp. Retighten the bolts after this, then run it for another day or two and then tighten again as needed. This will seat the gasket and the bolts will not back out.

I use a SHORT open end wrench and back the bolts out. Be careful backing them out because sometimes the radius of the pipe will only let you bring a bolt out so far. Then, you have to loosen the others, pull back on the flange and continue to get that one out. I leave both ends in because most gaskets will drop in and hand on the two end bolts. If you look at the gasket you can see what I mean. I use cheap ones (I think they are Mr. Gasket) and they seal fine. After a heat cycle, tighten them up again and drive away...

Just what has worked for me: Buy stock replacement gaskets from NAPA, that way one only has to loosen the bolts as aformentioned and the new gaskets slid in. Use anti-seize on the bolts, I use Mr Gasket bolts. Snap-on has a neat 7/16" wrench with different open end angles at each end, its a little pricey but worth it. As far as the cooling cycle comments go: Wait until the thing is stone cold before retightening and check it several times the first week or two and then at least once a month after that

I got some stainless bolts with both hex head and socket head. I can use either a 7/16" wrench or a 3/16" allen wrench.

I also use a crow-foot socket with an extension for the hard to reach rear bolts.

The gaskets I use are the cheap Mr. Gasket ones that my local parts house sells for $5.99 a pair.

As mentioned above, tighten 'em and drive the car. Let it cool overnight and tighten 'em again. Check 'em regularly.

Just wanted suggest also using permatex orange high heat RTV if you don't want them to leak..It works!

Originally posted by Importtech:
Just wanted suggest also using permatex orange high heat RTV if you don't want them to leak..It works! Hi all,

How about using the soft copper or steel type gaskets, in place of using the papper types, for the header and collectors?

I hear the metal gaskets last longer.. Or, has anybody else had any good or bad experiences with the metal vs papper gaskets?

Ken