Engine Tech - Carb swapped Bridgeport

Just purchased a 2.4 Liter Mercury Bridgeport with a 1750 Bullet in Australia. The engine as rebuilt a couple of years ago, and during the rebuild the electronic fuel injection system was replaced with carburetors. When I received the engine, the seller gave me the EFI system with the high compression heads.

Can you give me any suggestions as to why they would have done this? Also, could you provide any information on the 2.4 Liter Bridgeport engines in terms of reliability, horsepower, speed, or any general information?

The Mercury Bridgeport was Mercury’s racing engine throughout the 1980’s and early 90’s. They were available in carbureted and fuel-injected models, ranging from 230-245 rated horsepower. The Bridgeport can be very reliable if machine work is performed to the pistons to allow the port bridges to cool. This is a known weak point of this engine.

I could only guess why the fuel injection system was replaced with carburetors on your engine. Here goes: All ECU boxes, although very accessible, are very expensive – even in the United States. It is sometimes difficult to troubleshoot electronic fuel injection problems, and without a good source and availability parts that can be swapped for suspect bad pieces, the repair process can be a stressful undertaking. On the other hand, carburetors are very simple for most folks to tune, repair, and troubleshoot. If the EFI system had been the source of a problem, it would be easy to convert the engine as they did, and get on the water to enjoy the sport. That’s just a guess, however.

I have customers that have us modify their original, stock fishing engines to make big power, and the OEM fuel injection system on these production engines is incapable of feeding the newly-gained horsepower of the modified engine. The simple and less expensive solution in this case is to convert the engine to carburetors that can handle the needs of the modified engine. The customers are generally very pleased with the end result, and with the progressive jetting design of the newer carburetors, it is very easy for the amateur engine tuner to target areas that need a richer mixture as the engine transitions throughout the jetting circuits.

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