Tahoe540
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- Joined
- Aug 2, 2016
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I have just swapped a stock 454 to a pretty stout 555. I finally got it out and was expecting this motor to pull harder and turn some rpm. It hits a wall and just stops pulling around 4800 rpm. The motor should be around 650 HP. Same setup with 099 iron heads dynoed at 621 HP. It now has Brodix BB2 heads with shaft rockers and is 10:1. The stock motor pulled 4800rpm with the same pump.
I have a B/G pump that was rebuilt with a new stainless A, droop and a ride plate. The boat is a 21ft Hallett daycruiser.
I left the fuel lines in the boat and they are 3/8 hose all the way to the carb from the fuel tanks. I have read this could be a fuel starvation issue on the top end.
What I am planning
Because my lines from the tanks are only 3/8 I was going to run both tanks at the same time into a new filter head with 1/2 NPT threads. From the filter head outlet I was going to run 1/2 hose all the way to the carb. I am planning on buying a new 170gph pump and plum it with -8AN fittings to 1/2 hose barbs. I have also installed a new 1050 (4150 plate).
I am open to any suggestions or ideas why it is hitting a wall. This same combo pushed my 30ft Advantage offshore boat to 60mph at Lake Tahoe (6000 ft elevation).
I have a B/G pump that was rebuilt with a new stainless A, droop and a ride plate. The boat is a 21ft Hallett daycruiser.
I left the fuel lines in the boat and they are 3/8 hose all the way to the carb from the fuel tanks. I have read this could be a fuel starvation issue on the top end.
What I am planning
Because my lines from the tanks are only 3/8 I was going to run both tanks at the same time into a new filter head with 1/2 NPT threads. From the filter head outlet I was going to run 1/2 hose all the way to the carb. I am planning on buying a new 170gph pump and plum it with -8AN fittings to 1/2 hose barbs. I have also installed a new 1050 (4150 plate).
I am open to any suggestions or ideas why it is hitting a wall. This same combo pushed my 30ft Advantage offshore boat to 60mph at Lake Tahoe (6000 ft elevation).