Smaller than normal exhaust ports on a 318

[Anonymous]

Afternoon all,

My exploration into the strange world of MOPAR continues. Hoping you can help out with the latest problem.

Car is a 1969 Barracuda, RHD, with a 318 cc engine. Right exhaust manifold gasket had blown so I ordered new ones.

But when I cracked off the manifold, the exhaust ports are much smaller than the gasket. Square ports, 1inch wide by 1 and a half high (1 2/32, 1 15-17/32)

So I looked under the valve cover to check that the head casting number, and it came up as 2843675, which decodes to the factory header for that size and year engine. Confirmed at the same time that it was a 318 block.

Called the chaps at US Automotive, but they couldn't help. All the gaskets they could find had much larger ports.

Any suggestions as to why my exhaust ports are so small, and what gasket I need?

Thanks in advance.

Steve

[Kev]

Exhaust gaskets are larger to allow for porting(?), also I think they are generic to 273/318/340/360 which will obviuosly be a compromise on the smaller ones. DON'T WORRY! Are they severely coked up??

[Anonymous]

Hi Kev,

Hadnt thought about the point about them being generic for all sizes. That would mean they would be bigger than the smaller ports, (Doh). I'll give them a go and see what happens.

Are they coked up? You mean the exhaust ports? Not really, nice and black but not a lot come off on your finger.

[Kev]

Just measured my "Tarantula" intake ports and they tie in with your measurements for exhaust if this helps.

[Anonymous]

Steve, Felpro can supply gaskets for 318 ports only. I know this cos I fitted generic (big port) gaskets to my 318 and tey blew out very quickly.
I got mine from WASP.

[Anonymous]

get the manifold checked for flatness before you put it on, i had a 360 and it blew out the new gasket because it was warped like a banana!

[Anonymous]

Thanks or the advice guys.

[Kev]

Warped Bananas!