342 w/350 MAG Hill Marine prop update

Handymans342

Black_Diamond said:

~37 mph.  

Cruise at ~30 at 4k rpm.  

Calling it a win. 

37 ????????? Thats it? Thats not much faster than mine and way slower than @Raybo3 342. 

Did the VV show fuel usage at 4K rpm? If so, was it the same as before?

Black_Diamond

Honestly, mine has never run at speeds others get at WOT. No idea why. With these props and my cruise at 28-30, I'm pretty happy with the performance. 

I get my gph from my Floscan gauges. They are analog, no noticable difference. The mpg is up tho at 1.1-1.2 mpg. I was <1 before.  

Handymans342

Well that's fine

Michael T

I'm trying to remember the WOT/MPH of a slip mate's 342 with 337 Mags (6.2L)  I'm pretty sure the MPH was in the early 40's.  Other guys with 350 Mags in 342s were getting high 30's in the MPH. 350 Mags are great engines but a bit small IMO for a big hull like a 342 especially with a generator and load. I had twin 350 Mags in my 2013 EC 310 and that was a rocket - but a lighter hull. It went into the 40s easily and planed like lightening. That's why I am like a dog at a root regarding getting the biggest engines you can afford.  The difference in engine performance in the 350/EC360 is huge. Get 350/377 mags in that hull (and I have friends with each configuration) and the boat is IMO a dog. Put in 8.1s or 8.2s and it is a speed monster. 

Black_Diamond

At the time, I believe the only engine choices were the 350 MAG MPI or the 6.2 Horizon.  

The acceleration across the whole throttle range is impressive now.  Much less wake behind the boat too, that much aft lift from the props. 

Handymans342

I can't wait

Michael T

@Black_Diamond....you certainly appear to have tweaked the best possible performance from your boat which is all any of us can do. Nicely done.

Black_Diamond

@Michael T.  Thanks!

reneechris14

Sounds real good looks like it was a very good investment. I will put this on my list for some day $$.

bella-vita

 I have 350 mags no problem going 40 miles an hour 4100 rpm's I can hit 45 4800 rpm's  that's with half a tank's smooth waters with the current  against the current I'll lose 4 mph original 24 pitch props 4 people on bored 

bella-vita

J3ff

and what props do you have? what out drives?

Black_Diamond

Impressive!  With my original 24P props, good luck getting on plane with 4 people on board.  Quirk of my 342 I guess. 

Liberty44140

22P props on my bravo 3's with 350 mag. No planing issues. WOT is 41mph at around 4900 rpm. 

J3ff

Which is why we need to know what bella is running... 40 at 4100 rpm's is unheard of on these big boats.

bella-vita

24p bravo3 I have got on plane with 11 people and 2 dogs on board,took some work.but I do wish I had bigger motors more power always a plus

J3ff

Hmmm, wonder if fresh water has anything to do with it, do you have bottom paint on your boat?

Black_Diamond

Fresh water and Micron CSC to start. Moved to VC-17 this year.  

Michael T

@Liberty44140 IMO the main point of your post is that your engines are running in their RPM band which is very good. BTW - do you guys ever borrow a shop tach and mph gauge to check the accuracy of your in dash units? I have done this in the past. Most of the time my tach was good and the mph gauge was not - particularly at higher speeds.

davidbrooks

Still in the break in period on my out drive so i cant hit WOT for a little more.  BUT very happy.  I called Hill ordered 2 sets and had them at my door in 10 days.  No complaints at all.  As mentioned before I have done a lot of work but i just went back in the water with brand new bottom paint (micron csc), one rebuilt outdrive and new 22p props.  I have noticed the engines just feel smoother as if i am in the right gear now.  Getting up on plane and accelerating on plane is absolutely better.  At 3500 rpm and a little engine trim i am hitting 30mph.  Which before i was pulled out of the water wasn't possible.  

DanD2

What is the gear ratio on the B3's? Does anyone know if I would see the same results on a Volvo DP-S_

Liberty44140

@Michael T was just posting my numbers but yep I am within band and I think my numbers are in line with most 342s with regard to topping out in the low 40s on 22p. Perhaps I would get similar numbers to Bella with 24p props? Not sure. Funny you ask about the shop tach, we just did that last week. Both of my faria tachs are equally 200 rpm high at 3500 rpm. So at wot I see more like 5100 at the tach. Btw I am freshwater.

Black_Diamond

Just more info on the 20P Props.  I had a trip out on Sat with 5 adults...4 of course all as aft as you can get, 1/2: fuel/water/waste.  So pretty good loaded test. 

1. Even loaded up is is EASY to have a normal voice conversation.  That would have been a no-go before the prop switch. 

2.  Easy pop up on plane.  

3.  Need virtually no drive trimming up still. 

110% happy with the 4x4 Hill Marine props.  

raybo3

That's awesome bro. Glad it worked out for you...

Handymans342

Black_Diamond said:

Just more info on the 20P Props.  I had a trip out on Sat with 5 adults...4 of course all as aft as you can get, 1/2: fuel/water/waste.  So pretty good loaded test. 

1. Even loaded up is is EASY to have a normal voice conversation.  That would have been a no-go before the prop switch. 

2.  Easy pop up on plane.  

3.  Need virtually no drive trimming up still. 

110% happy with the 4x4 Hill Marine props.  

Well, did you trim up the drives anyway to see the result? When at full throttle on mine and I trim up the drives I usually pick up speed as well. 

Black_Diamond

Yes, I played with the drive trim numerous times since the prop switch.  Anything more than a fraction and I drop speed/cavitate.  There is SO much more aft lift with these props, I'm running much 'flatter' (very little bow lift).  

I used to trim about 1/2 way to the first trim mark on the gauge with Merc props. 

Handymans342

You may need bow lift one day in rough water

Dream_Inn

BD, it's funny you mention the whole trimming thing.  I've definitely noticed I've been trimming less.  Actually, this past weekend the admiral drove a little and I mentioned to her to not trim up as much.  She asked why, honestly I didn't put 2&2 together, but it makes sense.  I've also noticed the bow staying down a lot more.  I'm telling you, these props are amazing!!!

Wildboating

bella-vita said:

IT EXIST!!!  This is like an elusive unicorn i have been chasing.  4000+ Rpms and 40mph!!! Woah

Wildboating

davidbrooks said:

Still in the break in period on my out drive so i cant hit WOT for a little more.  BUT very happy.  I called Hill ordered 2 sets and had them at my door in 10 days.  No complaints at all.  As mentioned before I have done a lot of work but i just went back in the water with brand new bottom paint (micron csc), one rebuilt outdrive and new 22p props.  I have noticed the engines just feel smoother as if i am in the right gear now.  Getting up on plane and accelerating on plane is absolutely better.  At 3500 rpm and a little engine trim i am hitting 30mph.  Which before i was pulled out of the water wasn't possible.  

Which engine package do you have?