QSB4.5 Farallon 25’

[Sean]

Would the B4.5 work as a close coupled v-drive or does it need to be remote like the old 3.9-4bt due to vibration?

gas straight shaft to v-drive.

considering the 230 or 250hp versions for Farallon 25. With close coupled on a ZF63IV 1.5 ratio, 19”-4B prop, integral tanks and HD running gear (1.75” shafting and a real rudder).

goals: shorter engine (vs 6cyl) gives more internal space along with the integral tanks. Electronic engine less exhaust smell and quieter. 15-17knt cruise at 5-8gph at 9500lbs fully loaded for fishing. Semi-commercial use.

higher hp ratings to get up on plane, but able to stay on plane at less than 2gph/ liter.

would it work?  Do I need to get the weight aft with a remote V? I know you know the farallon repowers!

mahalo, Sean 

Topic

[Tony Athens]

All the RECON 5.9’s are the same price up to the 380 (all same exact engine–just an ECM calibration) .. So if you want a 5.9, go with the 380 and prop it LIGHT.. The added rpm to make 300 HP will make the boat noticeably slower in the harbor and be easier on the gear unless you are into shot-gun starts.  Depending on a few things, the cost will be similar by the time the dust settles.

For the wife: EPA T3 engines are “cleaner”, but both are very clean regardless. The 5.9 will be smoother than the 4.5. 

[Sean]

Cost/performance comparison

If both can be mounted close coupled what is the cost comparison between the new QSB4.5-250 and a recon QSB5.9-305? Running gear and trans would be the same, right?

seems like there would be more cruise HP and get on plane grunt with the 5.9?

any notable difference in noise and diesel exhaust smell between the Tier1/2 5.9 and the Tier3 4.5?

my wife likes the non-smelly gas V8, but I don’t like the safety and lack of range issues.

[Tony Athens]

Close coupled is good if the mounting is done right

[Sean]

Close or remote

Can the QSB 4.5 be close coupled on a ZF63IV or needs to be remote like a 4bt 3.9?

[Tony Athens]

I do see how you could get a 25Ft Farallon to weight over 8000 Lbs unless all of the original construction was water logged and over glassed–The QSB 4.5  250, done right would do you right.

[Sean]

Max operating weight

In your experience what would be the max safe operational weight of the 25 Farallon hull?

9500#?

Am I asking too much of the hull to carry

1000# people, fish, ice

700# 100gal diesel

cummins engine

450# 55gal live well water

[Tony Athens]

25 Farallon –QSB 4.5 –Close coupled V-drive

Done “Tony Right’, you’d be a happy camper… If the ready to fish Farallon is at 7000 lbs-ish, 16-18kts at 2.3 MPG is very doable–Trolling speeds at 4-5  mpg

 

 

[Author]

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