420 vs 425 Merc
09-28-2019 | 12:38 PM
#1
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From: Tennessee
420 vs 425 Merc
So on this 88’ Formula 357 I’m trying to figure out (and many of you have given great advice, thank you) in the brochure it lists the 420 as the standard motors for this model and year. The engines in my boat say 425. Are these newer? Any major differences I should be aware of as I attempt to tune the Holley Carbs?
09-28-2019 | 02:00 PM
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From: Toledo Oh
