Single manifold and exhaust system

[brucelee34]

I need a complete system for a 64 1800s. I am going back to single manifold as the twin does not fit the carbs and needs grinding to fit. I will gladly give you my twin manifold as part payment if you want.

[agent_strangelove]

Something must be wrong. Your car would have left the factory with the alumn. intake manifold and a single pipe exhaust manifold. They should fit just fine.

Where are up having to grind your carbs? Maybe we can help you figure this out....


Chris

[222s]

Is the problem due to different thicknesses of the flanges where the manifolds bolt up to the cylinder head?

Single downpipe would be a step backwards compared to a twin downpipe.

[brucelee34]

Chris/222 - Yes, the thickness of the twin downpipe flanges is causing the issue. I used 10 head to manifold gaskets cut in the appropriate places to counter the issue. I can;t see how I can fix this issue on a permanent basis wihtout having to grind away.

[940_Turbo]

The normal way people get round it is to get some more of the thick washers, cut them in half and use them as a spacer. Using extra gaskets will just blow after a while. The washer bodge is permanent.

[Derek UK]

You need some thick washers/spacers with a notch cut into the side to match the 2 manifolds. They can be made from a piece of brass rod or thick walled tube. Basically a hack saw, a vice and a file, plus a drill is needed if using rod. Some patience too to get the first one right. It's surprising that no one makes and sells a set. Maybe a little project for someone?
As said, a bad move, going back to the single down pipe.

[classicswede]

I do have an original single down pipe manifold for an early 1800. It is in very good shape but is more one for a totaly original car than a day to day car.

If you use your car often then I would consider a 4 brach manifold to overcome the problem.

[agent_strangelove]

As others have said, you can use half washers. I personally have a double down with the earlier manifold. My own was done by fishing in an extra long 1" end mill to cut the seats to be the same distance from the gasket surface. You need to have access to a Bridgeport mill or the like but it's nice to install them that way.

Classiswede suggested a header. If you spend the extra to get one of those, don't bother with the 4-1 ones. The double down ones from Volvo are better than those. If you go with a header, the 4-2-1 are the way to go....


Chris

[brucelee34]

Thanks to all who helped. I will take the half washer route as going back to single downpipe seems wrong.