We maintain several 450R powered boats. Singles and multi-engines. This includes a charter fishing boat with over 2500 hours on a quad set and no major issues. None of the others (20+) in our care are experiencing any problems.

Skater30: Why don’t you tell us the name of the dealer who is having so many problems with 450s? I’d avoid them like the plague.

I believe the best thing for boat engines is to run them, seems like the ones that always get a lot of hours with no problems are the ones that are used a lot in a somewhat shorter time.

There is a well respected dealer here in Fort Lauderdale that has had a TON of issues with 450's.

Well....if they ran and didnt have problems, they would get used more...lol

Out of sheer curiosity, what is the performance difference between 400's and 450's? Is it just a few mph, or is is 15 or 20 mph?

Check out the PBC video of Myrick and Rusty running a couple WP cats side by side at LOTO with one having 400’s and the other 450’s.

50 more HP. LOL, you laid that wide open.
Anyways I'd say speed difference is boat dependent.
And they claim the 450's have more torque down low.

These heavy users really skew our perception of how many hours we think an engine should last. Corrosion becomes a big factor the older they get.

Hi,

My Phantom 25 runs 88-89 mph with the 400R. With the same type prop (Max5) I expext 95 mph with the 450R. With a CNC 5bl cleaver, maybe a 2-4 mph more. Plus better accelleration

I learned back in 2011 when I bought my Verado 350 Sci that its imperative that the rigging of this type of engine is done by the book. If not you can run into all kind of issues.

MVH, Toffen

Rule 1 is that they are all hyper sensitive to good voltage/batteries.

Mine will run in some sort of protection mode that doesn’t trigger an alarm if they are started on low battery voltage. A normal user might have a heck of a time diagnosing that.
*not verados , was making a statement about fuel injected 4s OBs in general