New bravo III props w/ engine upgrade?

rabyers1 said:
Allright, the 383 has landed at the boatyard. I am going up to take a look tomorrow. My mechanic says it is a very impressive motor just sitting on the pallet. He mentioned something about the smell of new paint.
I feel like going there tonight!

Unfortunately, they don't have the right risers they need for the different exhaust manifolds and my particular application - so now we wait for those to arrive.
Click to expand...

So...what ever happened here? Are you in the water with this rig yet...any pics:huh: We're kind of hangin' here.

I want to know.:grin:
 
Sprink - Yes, I am pretty anxious myself to get the install done. Got the 383, but it came with the new style exhaust manifolds that have the external cooling water. These gave it a smaller totla rise- so we had to order 1" spacers to get to the right lift. These parts took a while to get.
 
The 383 is in and I have put about 1.5 hours on it during two short 45 minute runs on two consecutive days. So far, it is exactly as Sprink56 said - I hit the throttle and the torque push drops the bow over and I am grinning from ear to ear. Looks like top-end has improved quite a bit as well, but the biggest difference is just the ease of getting on plane. Man what an awesome motor compared to my tired old 5.7 EFI. I can't wait to get it properly broken in and loosened up. Thanks for the break-in advice Sprink!
 
RAB...wow...that's great news. I have been talking with Chris Dauth in Australia via e-mail and PM over the last 2 weeks. He got his 383 together and Dyno tested. It makes 400 HP at 4600~4800 RPM and his TQ peak is about 425 at 2750 RPM. His TQ curve is close to 400 ft. lbs flat curve from about 1800~2000 RPM to just over 4000 RPM when it starts to fall off....just perfect for his 27 weekender. He is finishing external accessories and going in the boat with it as I write this (Friday 1 PM) and may be in the water with it this weekend. They are 14 hours ahead of us there so he will probably let us know the results soon.

Thanks for sharing...show us a pic of that sweet engine installed.:thumbsup:
 
I'm here !!

The motor is finished, ready to start, and sitting in the trailer ready to go down to the boat. :smt038
They shifted the boat out into the shipyard yesterday afternoon (Friday) and I spent all afternoon cleaning out the bilge. I knocked out those remaining pieces of the bottom transom bolts and gave the whole area a good clean up.

So, it's Saturday morning, and it's raining :smt013 . Anyway, it looks as though it may clear up soon.

I'll go to the boat shortly and get the transom plate bolted in, with a bit of luck I'll get the engine in today.

Glad yours is running great RAB, I can't wait 'till mine hits the water again. :thumbsup:

John, I'll email some pictures later this afternoon.
 
I just realized how really cool this is...we have guys on opposite sides of the globe communicating with each other about their common interest in each others boat projects.

Is this a great forum or what?:thumbsup:
 
It is definitely very cool. Chris - Congratulations on getting your engine finished. Good luck getting it in your boat. I am anxious to get out and do some real break-in and testing, but family obligations this weekend and work travel will prevent that for the next week. You will probably get ahead of me in hours logged before I get back to it next weekend. I will also get some pictures posted then.
 
Well, the engine is in. Lifted the motor out of the trailer at 2 PM, came up out of the engine room at 2:20, all bolted down. I spent the afternoon connecting things up. So tomorrow, I'll flash her up. I have to do the engine alignment yet, but I'll get the motor running first and make sure there is no leaks in the cooling system etc. I have a hose connection between the skin ball valve and the raw water pump, so no problems there.

Keep you posted. BTW, I took more pictures so I'll post them up and send them on !!
 
Damn, almost makes me want to yank my Mags out.....looking forward to the pictures and Chris flashing her up too. RAB, looks like a rainy weekend, get that family and work stuff out of the way so you can get back at logging in those breakin hours : - )
 
Chris,

Your motor looks awesome sitting in the engine compartment. I am a little envious that you are doing this yourself. My leg injury has caused me to sit on the sidelines while a paid mechanic put my motor in. I took a quick cellphone pic this evening of the 383 in the boat:

View attachment 7167
 
any updates or more pictures?
Congrats on the repower! Sounds like a nice project
 
I have about 7 hours on the 383 now and here is some performance results after a bit of fine tuning.
On the dyno, the motor was tuned on premium 98 octane fuel but there is 300 liters of 89 in the tank, so I had to take 2 degrees out of the ignition timing to prevent detonation at the higher revs.
She was running a bit lean on the top end, 4000rpm + so a change of control rods in the carb fixed that. The tips of the rods are now 0.005" smaller than the origionals.

On the dyno she max'd out at 400HP @ 3900 rpm and 400 ft/lbs of torque. After 4000RPM she slowly falls away. Maybe a bit more off the carb control rods will extend the range, give her some more to drink :thumbsup: My specs were to have the best output between 3000 and 4000 rpm. At 3000 rpm she puts out 345hp at 425 ft/lbs of torque.
I usually cruise at about 3300 rpm.

A test run last Monday, weather was almost calm, with the wind, I got 39 knots at 4100 rpm and the run back against the wind, I got 35-6 knots at 4000 rpm. ( GPS ) May be I could have gotten a bit more but I'm taking it easy on the new motor.

The fuel burn on that run was 1.2 liters per nM. Only me on board. On Wednesday, we took out some friends for the day , 5 on board, travelled 42 nm and used 61 liters or used 1.45 liters per nm.

Having the motor blue printed and hand balanced has made a remarkable difference in the smoothness and quietness, you wouldn't know there was a motor in the boat.

All I have to do is use it. Summer is almost with us here so I don't think I have a problem there :thumbsup:

.
 
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