How To Get More Power Out Of A 4.3 Mercruiser. How many hours does a mercruiser 4.3 last? The 4.3 is a good platform, but if you're looking for significant performance gains it would be best to go to a v8.
So how much power can you make with a 4.3l. Salt or fresh, closed cooling vs raw water cooling make a big difference. Mercury makes this engine itself and does not source the blocks from gm.
Contact comp after you choose a cam and get the required springs for.500 lift on a vortec head. The only thing to do to make it significantly faster (i'm talking 5 mph +) is to add horsepower and torque. According to mercury marine, the engine is a good fit for runabouts up to 19 feet, pontoon boats and fishing boats.
The highest you can get is usually around 93 to 94 octane. About 250hp with the vortec heads, a good cam and the the above recommended modifications. If your engine has fuel injection, then toss your throttle body, computer and intake manifold into the trash and set it on fire.
Depending on the year model you may have to change the ignition amplifier as some have a different timing curve on the 2 and 4 barrel. The 3.0 l mercruiser engine. Noticed a slight vibration at 2000 rpm.
This is a very inexpensive way that you may get a bit extra power. Tips on getting more horsepower on 4.3 merc simple cheap easy mods, for a bit more hp: Your best solution is to buy a different rig with a larger motor.
Hellocustomer there are several different ways to increase power output, but the best and simplest would be to install the 4 barrel intake and marine carb this will bump you to 260+hp. If we can redirect some of that power from turning accessories to help maintain that speed. There are a few questions you should ask yourself before you proceed, and that we will need to know the answers to before any of us can recommend specific equipment to you.