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Old 09-25-2023 | 06:40 AM
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Aha! What exhaust did you run back then? Was exhaust options also limited?
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Old 09-25-2023 | 12:37 PM
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Originally Posted by jocke
Aha! What exhaust did you run back then? Was exhaust options also limited?
If you go back and read my previous posts, then you will see what I have stated about exhausts systems---even from back then in the early 80's. These days you have even more options for aftermarket exhaust systems. You absolutely DO NOT want to reuse the stock Merc heavy cast iron exhaust manifolds...

---in a nutshell, they're too crude and choke the exhaust flow and will kill any potential power gains that you are trying to achieve.

But if you really want to make good power for these BBC marine engines, then you need a decent open breathing dry aftermarket water jacketed exhaust system--- one good example would be the Stainless Marine makes a decent manifold system for the BBC ...

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Old 09-25-2023 | 04:04 PM
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I’m a bit afraid that the completely dry systems will be TOO loud. If that’s even possible. My cousin had a ski boat with a dry system and the people in the marina where he kept his boat made a petition for him to not be able to run it after 10pm. It’s the same one where I keep my boat as well.

Feels bad to buy a system with mufflers though…
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Old 10-04-2023 | 11:00 AM
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Alright. I’m back with the verdict;









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Old 10-04-2023 | 11:40 AM
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A 2-bolt block. Not sure what these heads are though. With this knowledge what I’m looking for changed a bit. I think only a modest build with stock exhaust is enough. If there’s any idea of doing that. Since finding someone that’s capable of a line hone is a bit harder where I live. Also feels like it’s not worth it to invest as much in a 2 bolt block
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Old 10-04-2023 | 12:01 PM
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Speedmaster PCE288.1010 Procomp Electronics Main Cap Girdles | Summit Racing
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Old 03-03-2024 | 05:57 AM
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I'm back and after giving it some thought I decided to go the budget route. It'll be more of a refresher with some higher compression and a new cam than a full blown performance build. The main reason for this is because the uncertainty of the performance of my hull and because my block was a 2-bolt.

This is my order from summit:




The block is being bored as of this post and I started disassembling and sand blasting my heads. 1 out of 16 valve seals wasn't cracked. I was also planning on porting the heads to fit the oval port gasket but it seems I don't have enough material to remove that much. Anyone with any experience porting the peanut heads? I'll try to update as I go

Last edited by jocke; 03-03-2024 at 06:21 AM.
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Old 03-03-2024 | 09:57 AM
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No need to enlarge the port entry of the heads, dont waste your time! the restriction is deeper in the port, atleast it was in my 360 casting peanut heads.
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Old 03-05-2024 | 02:39 AM
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Originally Posted by JaniH
No need to enlarge the port entry of the heads, dont waste your time! the restriction is deeper in the port, atleast it was in my 360 casting peanut heads.
Thanks for the reply! Not even worth it to try to port match the intake?
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Old 03-29-2024 | 11:53 AM
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Anyone know what bore headgasket i should get? Seems I bought the wrong one and the bore of the gasket is always bigger than the bore of the cylinders it seems
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