Re: Anyone ever put a 25hp carb on 20hp 1999
There's much more involved that carb size for 2 cycle power. The engine as designed is a balance, and if you fit something else to it without being able to manage that balance, you could cause trouble. At any rate, the outcome will likely be nill, negative, or have severe unintended consequences.
An example is that if you put bigger carbs on a V6 fishing motor (150 or 176) they will have to be re-jetted, probably multiple times to get it right, and then you are going to trade off much hole shot and mid range for a slight gain at the top. Make a mistake setting it up and grenade the power head.
Now if you're porting, decking, gutting the exhaust chest, changing tuners, installing a PCU, etc., then the larger carbs are probably part of the overall project.
Look up the parts diagrams for both motors. If the block, crank, pistons, and heads (if they exist) are the same, then it might work. Block and pistons are critical, because bore, stroke, and porting design and timing all are big factors. In other words, just because it's the same bore and stroke doesn't mean it's the same volumetric design.
hope it helps
John
