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Hello all, as I am finished with the rear supsension and have the car back to a rolling chassis, the next step is firing up
the engine. I still have to assemble some
of it though, the intake manifold, valve covers, and headers. What do you guys suggest is the best way to put on each of these? Which ones need rtv? Which ones don't? Well I'm
asking more about the intake and the valve covers, I have heard those are notorious for leaking. Which is what I don't want. So just share with me what you would be doing if you were in my situation. Thanks!
 

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Exhaust - Dry gaskets. Anti seize on the threads, and wire lock header bolts.

However, and this may sound odd, but don't lock them on 1st torque cycle. Let the engine heat up and cool down a few time. Re-torque before and after every heat cycle. Do that a few times, them wire lock the bolts. Bolts stretch and threads change ever so slightly. You'll get a very good tight seal if you let it heat up and cool down a few times...re torquing in between, before locking.

Intake - Dry gaskets, except for a glob of RTV in the corners where the block, intake, and cylinder head all meet. Use a 3/8" bead of RTV instead of the front and rear rubber seals. Lay the bead, drop the intake, and let it cure for the recommended period of time.

Use anti seize on the bolts and lock washers. Like everything else on the engine, re torque all the bolts before and after several heat cycles.

Valve Covers - That can be tricky, and really depends on your results from the 1st seal. Make sure the covers are square. Check them on a perfectly flat surface. Use Fel-Pro rubber gaskets, torque exactly to spec. Again, anti seize on the bolts, and use load spreaders and lock washers under the bolts. The load spreaders will evenly distribute the clamping force and not distort the covers.

Good luck.
 

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:agree:
The only deviation in the above becomes preference from experience.
The valve covers always seem to be a leak point. As stated above, make sure the cover flanges are straight. Especially around the bolt holes where they tend to get over tightened. I place them loosely, upside down in a vise, and use a hammer to level them off. Sight down the entire cover to check for bowing, etc...
Everybody seems to have a method for sealing them. I have never had much luck with a dry gasket here, no matter the material. My personal preference is using just RTV here, letting it set up for a few minutes first.
If you're using gaskets, I always RTV the gasket to head edge first, then RTV the cover. Let it set-up, and just snug 'em down easy. Rubber gaskets tend to squirt and squirm around, and cork tends to crush easy. I'll leave 'em for a few hours, then I pull the bolts, clean 'em and use an easy thread lock before final torque down. Bolt spreaders are the way to go, and come in chrome too.

I've heard that the high-temp copper sealer helps with header gasket seal, but never tried this.

Good Luck and make it fun! :cheers:
 

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:agree:also i like to use permatex or a light smear of rtv around the water passage on the intake gasket,stops them seeping.
retighten after heat cycles for sure:thumbsup:
 

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i really do not like RTV. I feel it is the "easy" way out...and sloppy too. Make sure the sealing surface is flat and square. if you use a cork or paper gasket, use a propper gasket sealer- permatex makes a nice one. Or you can get a quality butyl rubber valve cover gasket and not worry about a leak. they typically come with metal inserts around the bolt holes to prevent crushing it.

Wire locking the exhaust bolts is a good idea, but can be a pita. one option are Stage 8 locking header bolts. I have them and they do not come loose- and are far easier to install and remove.

Absolutely use anti-sieze on the header bolts. I prefer to use a thread lubricant (typically ARP) for most of the other fasteners. It allows for a first pass torque and prevents galling, siezing, and rust.
 

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I don't know for sure but would expect there are thicker rubber type gaskets for the covers, and haven't done any SBC intake manifold work but have used the gaskets with the silicone beads on them on other motors successfully.

On your covers (as well as oil pan and front cover), I always clean the bolt threads really well with solvent (I always just use carb spray, real handy, I don't have a parts washer) and do the same with the bolt holes. Then dry with compressed air and blow the holes out, making sure all threads are also dry.

When I assemble I use a dab of blue Loctite and torque to recommended specs, then leave sit overnite before starting the engine. In over 40 yrs of doing this I have very rarely experienced even a seep.
 
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