23DV Repower F350?

[Cculp218]

I am going to be repowering my 2003 23DV soon (sooner the better), Original plan was a new Yamaha F300 or Suzuki DF300, But I have been watching for used motors as well. There seems to be a lot of good deals on Yamaha F350s and not quite as many F300s for sale, for obvious reasons given the issues with the older F350s. So my question is has anyone ever put a 350 on the back of a DV? The F300 is listed at 562lb and the F350 is listed at 763lb. Considering there are boats rigged with twin F150s at ~950lbs total, in theory it could handle the weight of the V8 F350. The 50HP  gain is likely not worth the 200lb difference in weight, but still weighing in ~200lb less than a similar boat setup with twin F150s I think it could work. Realistically buying a used F350 ~5 years old or so then sourcing my own Digital rigging ( need digital for rigging 2 stations) I could come out at about 50% of the cost of a new dealer rigged and installed F300 (~$30k). Then maybe in few years down the road go with a new motor and already have the rigging in place.

Any input is appreciated!

[DonV]

V-8 Merc 300. Here's the results from a friend who just re-powered his 23' SeaCraft which is quite similar to the 23DV.

http://www.classicseacraft.com/community/showthread.php?t=30497

I would "Run Forrest run" from a F350.

 

[Cculp218]

@DonV Seems to be quite a few out there though with the "flywheel and ECM upgrade" which was needed to resolve the issues they had, or even going with a "C" series motor which were the later models that were less problematic. For the sake of being cost effective with my refit I'm looking at used options. The mercury is impressive with the weight to power ratio.

[Lap it Up]

Just my thoughts and opinion, but I would look into any fly by wire 4.2L Yamaha and then tune it with either Simon Motorsports or Nizpro.  You will achieve similar HP numbers to the F350 and it will be lighter and more reliable.  

[Cculp218]

@Lap it Up At this point I have written off the idea of the 350, not worth the added weight for little horsepower gains and lower efficiency from the v8 from what I have read as well as all the issues they have.

 I did a little research on nizpro the other day. Would definitely be in the cards if I could find a deal on a 225 or 250 to get me up over 300hp I think they advertise as 320hp after tuning. From what it shows on their site the Flash is the same for all 3 of the 4.2l motors,  So essentially you are paying the same amount for different levels of added power?  I didn't look at pricing, but based on which motor is being tuned, ie. the 225 has the largest gains because its the lowest hp rating gaining 95hp, Compared to 70hp for the 250, then 20 hp for the 300.

I'm second in line for a 2011 F300 that's very clean with a brand new lower unit, so if that deal falls through ill be able to grab it and get back to fishing.

 

[Lap it Up]

All the 4.2L Yamaha power heads are exactly the same.  The only thing that changes is ECM mapping.  The 4.2L 200 would benefit the most from tuning and i have heard true dyno numbers are exceeding 320 HP.  

HoneyB and BradM know a lot more than i do on the subject.  Give them a shout.    

[Cculp218]

I thought the 200 was an i4 2.8, unless its the 200sho?

[lurem]

From what I understand there are 2-200 HP models for the Yamaha. The F200 is an i-4 and the SHO is a 4.2L V-6. The SHO is available for the upgraded ECM.

[lurem]

On 12/1/2020 at 3:17 PM, Lap it Up said:

Just my thoughts and opinion, but I would look into any fly by wire 4.2L Yamaha and then tune it with either Simon Motorsports or Nizpro.  You will achieve similar HP numbers to the F350 and it will be lighter and more reliable.  

I don't know if you need a 20" shaft or 25" shaft but why not look for a SHO 200/225  (used) and purchase that? With the money you saved buy the simon ECM and boost it to 300/320 HP?  If you have a Yamaha now you can use the same controls and then only have to worry about dialing in the correct prop.

just sayin?

[Cculp218]

@lurem

The boat had a 2001 Yamaha 250 ox66 when I bought it, I pulled it and sold it along with all the mechanical rigging a couple weeks later. Whatever I buy will need to have digital controls for rigging the second station I have added, looks like the SHO are only mechanical controls.

I have a line on a 2011 F300 DEC motor, but I'm a backup as of now if deal falls through.  But I have also been looking for 4.2L 225/250  that I can have flashed.

[CapeMike]

Might get scoffed at here, but has anyone heard any feedback or know anyone running twin 115’s?  General consensus is that the twin 150’s are too much weight….hear of any performance numbers from twin 115’s?  Obviously it’s nothing compared to a single 300, but I’d be interested to hear.