Magnum Head Qs

[billshotrod]

I was wondering if the 340 hp manifolds from 1968-1970 will fit on magnum heads

 

[AdamR]

Yes, They will bolt right up.

 

[billshotrod]

thanks

 

[bobscuda67]

They do bolt up, but they have a difference in height of the ports and they will leak at the bottom of the manifold. Bob

 

[AdamR]

Are you sure ? I thought the ports are actually smaller ?

Lay a gasket over the ports and check. I have never heard of that before.

 

[bobscuda67]

Yea Adam, I'm sure. I did the same thing myself. The magnum head has a small port on the exhaust, the same as a 318 port, and the hipo 340 exhaust manifold is a tall port to match the 340 head.
I made steel plates with a magnum hole size and a 340 manifold outside diameter.
Don't feel bad, many people don't know this. I contacted Hughe's engines and they said they never herd of it either.

 

[AdamR]

well you learn something new everyday.

 

[TheDemonator]

Yes it is true. Most people never have the "honor" of finding this out though, because they usually go with headers rather than manifolds. There are no problems with headers on magnum headed LA engines that I know of.

 

[billshotrod]

what did you use to make a template do you have one if possible

 

[1966 dart wagon]

good info cause i just got some factory manifolds from a friend who put headers on his 95 ram. well at least i still got em, i'll maybe able to use them some time

 

[bobscuda67]

what did you use to make a template do you have one if possible

I used the 340 manifold as a template, and a magnum gasket for the port size.