carborator question

[Otto cv23]

Here's the question. Im running the 350 chevy 260 mercruiser with the standard rochester carb. Would there be any performance advantage other than throttle response in changing to the Holley 650 rochester replacement carb model 80552.. This unit costs over 500.00 so there would have to be a dramatic increase in speed to justify the cost to me. Has anybody here tried this carb and was it worth the it and did it increase your top end?
Thanks

[V153]

Don't have any marine experience with Holley carbs but I put a 650 on my '72 Cutlass years ago. Found it ran better with the Q-jet.

[Jason]

For $500 you could probably do cam, Vortec heads, and intake and get more bang for your buck! I heard the q-jet is good for marine. Otherwise Edelbrock.

[75starflight]

For $500 you could probably do cam, Vortec heads, and intake and get more bang for your buck! I heard the q-jet is good for marine. Otherwise Edelbrock.

I agree that is the way I am going with my engine build for my cvz project. I have been told by several people the Q-jet is the way to go for a four barrel.

[Otto cv23]

Thank you all  Ill stay with the q-jet

[kert0307]

I'm using a Holley marine carb on my CVX. I like it, but I was able to find a good used one, so I think I only have around $150 in it.

[cv-19]

 I replaced the Qjet on my 455 Olds with the same size Holley with no performace gains .It did idle better with the Holley.