55 322 Exhaust Manifold Gaskets or Not?

[buickbrothers]

When I rebuilt my 322 I bought my parts from Centerville auto in CA. They indicated "NO gaskets on exhaust manifolds were they bolt to the heads! That's right, gaskets will cause the manifolds to crack". I have successfully done the engine start and break-in. However, I have some exhaust manifold leaks that I need to resolve. I plan to gentle use a file to ensure flatness on the manifolds and head ports. I was also planning to use a copper coat gasket sealer on the metal-to-metal mount. My question: is everyone else not using exhaust manifold gaskets and what did you do to eliminate exhaust leaks?  

[avgwarhawk]

I do not use gaskets. Even with a different set of heads. Knock on wood they mated well.  You can use the sealer you described to help stop a small leak.  Lightly filing should help but I think the sealant will handle the problem. 

[60FlatTop]

'60 Electra and '64 Riviera with no gaskets. Tried gaskets once but they leaked.

 

I don't have the French locks on the Electra and I did have to snug the manifold bolts up back around 2011.

[KAD36]

No gaskets is factory correct, make sure your manifolds mating surface is straight and true and it should work fine.  That being said my 55 engine had gaskets for many years and xx thousand miles to seal a manifold leak with no issues.  I barely torqued the bolts though and just checked them at oil changes. The French locks had disintegrated. If you choose gaskets do not torque them down or there is a high risk of cracking the ears on the manifold - you’ll just have to manage that interface.
 

When the 55 motor blew up and the 56 motor with 56 manifolds went in I mindlessly carried the gaskets forward but if I had to do it all over again a skim coat of high temp sealer as suggested would be my preferred approach.  Run them along piece of sandpaper or emery cloth glued to a flat surface to get an idea of high/low spots, assess the situation and pick your approach.  Good luck

 

[old-tank]

Best to take the manifolds to a machine shop true and clean up the surfaces.  Then assemble with a small amount of high temp RTV.  Real easy right now to slip some gaskets in with the crossover attached.  I have driven many miles both ways with no problems.

[buickbrothers]

Thank you all for the  feedback. I'll stick with the no gasket approach and true-up the mating surfaces plus use the sealer. Only two had leaks so I'm not is bad shape - just needs some tweaking. 2nd question. I rebuilt the carburetor (first time I've ever done that) and the engine ran great during the break-in. I followed the shop manual instructions to set the carburetor. However, I see some pretty black smut in my new pipes which I believe means it is running very rich. I was expecting a grey/white burn-off. I also switched from points to a PerTronix Ignitor Ignition so I was expecting a cleaner/hotter fuel burn. Any pointers on how to adjust/lean out this carburetor for a cleaner fuel burn?   

[KAD36]

^- best approach.

 

question 2 -

What carb do you have - maybe some one knows something specific to the WCFB or Rochester rebuild would have something to check.

 

If you think it’s together right and running well, then how much opportunity have you had to drive it and is the exhaust gas actually coming out black?  Drive it more.  That grey burn off is usually on the plugs. It takes long, fully warmed up runs like on the highway to get the tan/grey burn you may be thinking of.

 

If you really feel the urge to do some quick “trust and verify” settings without tearing into anything major my thought is check in the following order the choke setting to make sure it’s coming off closed quick enough, mixture screws “generally” fall between 1.5-2.25 turns out but every situation is unique, verify plug temperature range correct and gap set right, and dwell and timing - you can go 7-8 deg advance no issues.  A lot of us run it there. 

Pertronix opinions and experience of “more better” or “burn it where it sits” will vary across the forum team.  It’s never been on my car but others run with it and will surely chime in.
 

Get the choke, plug temp and mixture right and drive it more than 30 min at a time - if the carb is built right those are the biggies before you go looking for that burn off pattern JMHO

 

 

[buickbrothers]

Thanks Ken. I have the 4 barrel WCFB carb. Sounds like I'll have to wait a while before I can get it totally right as the car is not back together and drivable yet. I'm neck deep in painting the car at this time (another first time skill development since they wanted $25-$30k). Here's some pic's to give you a feel. The body is in primer, but the hood is done. It's been a battle of killing rust since last year! 

[KAD36]

Looks great!  Just wear shades, keep the bugs out of your teeth and head on down the road…..🤣

Good for you to go the self taught route. Looks like you are diving in and doing good work.  Thanks for showing your project and interested in following along.