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Old 04-05-2010, 05:21 PM
missinginaction missinginaction is offline
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Center Riser Manifolds

Well it's time to finish up the restoration on my 73 SIlverton. She'll need new manifolds and mufflers as part of this process. I see that the log style manifolds originally installed are no longer produced, Looks like Osco, Barr and a few others make generic center riser manifolds for the 302 Ford that I'm using.

Does anyone have any opinions on weather any of these brands are superior to the others? I've looked around but don't see any posts on this specific topic.

Any muffler comments would also be welcome. I'm leaning towards Centek Vernatone MK II's. I like it Q U I E T!

Thanks!

Missinginaction
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Old 04-05-2010, 08:37 PM
TollyWally TollyWally is offline
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I've generally heard good things about both BAR and Osco. What flavor was your stock marinization package? I have a new set of manifolds out in the shop to replace my stock Volvo set up. I think they are Osco's but I am too lazy to go out and check.

I've got the mufflers you mentioned, 3.5 x 24 or so. On the advice of my boat yard buddies I added hose extensions outboard of the transom and exit underwater. They are still louder than I favor. I think running more water through them may also help. I'm interested in what others more knowledgable might say.

I did get a little more back pressure at idle and had to reset my carb. All was well. At higher speeds the stern lifts and the exhaust exits freely into the atmosphere.
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Old 04-09-2010, 09:11 AM
BMcF BMcF is offline
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The Barr's on the 302 in my Donzi are pushing 20 years old and still hanging in there. I acid vat them about every three or 4 years and treat with Ospho...

Oscos are about the same product IMO..I don't have a preference for one over the other.
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Old 04-11-2010, 06:22 AM
missinginaction missinginaction is offline
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Thanks for the responses guys.

Tolly, I've got a 3" ID set up, the standard dual exhaust raw water cooled. I'm considering (haven't made any decision yet) going with a waterlift muffler. I could squeeze two back there but I'm thinking that I could perhaps run both my pipes into a Y configuration and just use one muffler. I'm not so worried about back pressure as I don't run this little engine that hard. The boat is underpowered for it's size and I generally just run at displacement speeds, even though it's a planing hull.

Regards,

T3
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Old 04-11-2010, 12:18 PM
TollyWally TollyWally is offline
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Mine must be 3" too, it wouldn't make sense that they'd have both 3 and 3.5. I'll be interested in what ever you do. Keep us posted.
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