Advice

Tail_Gunner

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3M43Je3N75G65H75M4cbjd879f51da702145c.jpg


Well gonna due a project boat again with a bit more horse power involved...454 and a bravo 2. Gonna build that motor to about 400 hp but i have no ideal what to look for as potential problem's..Will a bravo 2 handle that much power??? Is a Bravo two a good drive....As to the rest of the boat..this should be fun 22' mirage cuddy 88 vintage
 

HT32BSX115

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Re: Advice

Howdy,

I think the Bravos generally are good for a fair amount of HP B1,2,3 (400 and more) and unless you're going to put a Whipple Charger on it, I don't think a N/A 454 will be too much power

I don't think the Bravo II is known for high HP hotrod boats though.

You might consider selling the Bravo II (they're in demand for big cruisers) and get a late model Bravo ONE 1.5:1 drive.
(if it were me I'd get a Bravo III but I'm biased!)

Cheers,

Rick
 

Tail_Gunner

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Re: Advice

Learned someting there it seems the 2 is setup as a pusher...And SEI does not make a bravo replacement
 

MarkSee

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Re: Advice

Will a bravo 2 handle that much power??? Is a Bravo two a good drive....As to the rest of the boat..this should be fun 22' mirage cuddy

Seems like you'd want a Bravo 1 drive for a 22 foot go-fast boat.

A buddy has a built 454/B1 in a 21 foot Caliber 1 and that will get into the 70's.

The below link-article seems to point to a B2 being in heavier and twin applications.

Choosing MerCruiser Bravo 1, 2, 3 and Alpha One Boat Outdrives | Suite101

Mark
 

Bondo

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Re: Advice

Ayuh,.... I agree, the hull in that picture begs for a B-1, or B-3, not a B-2....

The B-2 is more of a houseboat/ barge drive, with a Massive prop...
 

Tail_Gunner

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Tail_Gunner

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Re: Advice

3M43Je3N75G65H75M4cbjd879f51da702145c.jpg



1990%20Mirage%20257%20freeboard



Simple stuff huh....
 

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HT32BSX115

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Re: Advice

The engine you're suggesting is a 400 CRANKSHAFT HP engine?

You're starting with 330 crankshaft HP............ upping (only) 70hp won't IMHO give you a spectacular increase in speed.

You'll want a final ratio of 1.5:1 for "best" performance with a Bravo ONE I believe.

In any event, the boat will perform admirably with that engine and a Bravo I.

I don't think you'll be unhappy.

If it were me, I would do a Bravo III just for the hole-shot and low speed handling ..........see my sig......... I removed a similarly powered single prop engine/drive and replaced it with a dual-contra-rotating prop drive.............. I started out looking for a Bravo I too but settled on the Bravo III because I found it first for the best desl. I was VERY sceptical of doing the B3.........but now would NOT go back.

The top speed wouldn't be much more than 5 mph less. You would need to find a Bravo III lower though (ebay etc) and the "trade" price wouldn't probably be all that much (selling your B2 lower, buying a B3 lower) but you would have to buy a set of props and the ratio might not be optimum.

You wouldn't want a 1.5 ratio in a Bravo III with a boat that big. I think a 1.81 would be the highest you would want. (then you would want to consider selling your Bravo II outright and just get the "right" Bravo III if you went that way...........

Your choice of swapping the lower is probably the most economical only if the ratio is going to be right.

If you currently have a 2.0:1 Bravo II, it might not be optimum with a Bravo I lower because it may force you to a high pitch prop to compensate......
 

Tail_Gunner

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Re: Advice

Your right about the engine hp..for now i am going to use that as a cost effective baseline. As to the gearing...that was dissapointing and takes me back to the drawing board......Look at what done to the orignal drive....:facepalm: i doubt there is good resale there..only god know's why they did that.
3G43L83H25Nf5G85Z1cbjd50d8c93b2e4188e.jpg


Top end is going to be a big deal with this boat it is a joint venture so i have to maximize that..A set of tab's and the right four blade will have to do. I can just see the other party being a bit careless and dinging a $1600 set of prop's...so i will avoid that potential fallout..:D
 

HT32BSX115

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Re: Advice

Top end is going to be a big deal with this boat it is a joint venture so i have to maximize that..A set of tab's and the right four blade will have to do. I can just see the other party being a bit careless and dinging a $1600 set of prop's...so i will avoid that potential fallout..:D

Looks like it has Tabs on it? (Bennetts?) I have the same ones.

$1600? I bought a set of 26p props for $600 and see 24p props for $500-600 frequently on EBAY......

The drive (lower) in the above picture doesn't look like a Bravo II.
 

Tail_Gunner

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Re: Advice and upate

Re: Advice and upate

Well that little jewel had a few more problems than i was going to deal with..ill post a few pic's. However i stepped right into to last night ...1987 217 intruder....200hours on a new 454 and new drive...the boat owned by a little old lady..er man, It is flawless dunno how that happened but it did and the deal was rightttttttt.

However as in all thing's perfection is never attainable but close ooo the bad new's......It has a aplha one drive...:facepalm: So here i am the next day with some sober thought's..err question's. Can i beef up a alpha...do i add a drive shower.....do i just drive and bust it..or do i sell it and add a bravo one...On the new bravo drive--err used can i just bolt up the right stuff or do i have to do some cutting..

454 330hp....3850lbs dry.....Not going to be a ski hauler just 4-6 people and yes i will run to the top say for 5 minutes but most of the crusing will be at 3500..4000 rpm. I will post pic's later it is almost without flaw...Just need to update the 90's color's a bit.
 

Bondo

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Re: Advice and upate

Re: Advice and upate

Well that little jewel had a few more problems than i was going to deal with..ill post a few pic's. However i stepped right into to last night ...1987 217 intruder....200hours on a new 454 and new drive...the boat owned by a little old lady..er man, It is flawless dunno how that happened but it did and the deal was rightttttttt.

However as in all thing's perfection is never attainable but close ooo the bad new's......It has a aplha one drive...:facepalm: So here i am the next day with some sober thought's..err question's. Can i beef up a alpha...do i add a drive shower.....do i just drive and bust it..or do i sell it and add a bravo one...On the new bravo drive--err used can i just bolt up the right stuff or do i have to do some cutting..

454 330hp....3850lbs dry.....Not going to be a ski hauler just 4-6 people and yes i will run to the top say for 5 minutes but most of the crusing will be at 3500..4000 rpm. I will post pic's later it is almost without flaw...Just need to update the 90's color's a bit.

Ayuh,.... The Alpha 1, Aftermarket drives are $1500., Brand New,....

Run what ya got til it pukes, 'n throw on another 1....

Even Used, the Bravo conversion is a quite a few Alphas away....

Don't Beat it to badly, 'n don't be catchin' Air, just Run it... ;)

Btw, transom work would be drillin' 2 more 1/2" holes, regardless what else ya bolt in...
 

Tail_Gunner

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Re: Advice and upate

Re: Advice and upate

Don't Beat it to badly, 'n don't be catchin' Air, just Run it...

That is the second time i have heard that both from verteran's "Catchin Air"...Does the drive spin up that fast in air???? I assumed it was tourqe that broke the drive...heat to??? I been envisioning bent or twisted drive shaft's?

My little wellcraft sx drive is alway's Catchin Air....Rev limitier pop'n..:laugh:
 

Bondo

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Re: Advice and upate

Re: Advice and upate

Don't Beat it to badly, 'n don't be catchin' Air, just Run it...

That is the second time i have heard that both from verteran's "Catchin Air"...Does the drive spin up that fast in air???? I assumed it was tourqe that broke the drive...heat to??? I been envisioning bent or twisted drive shaft's?

My little wellcraft sx drive is alway's Catchin Air....Rev limitier pop'n..:laugh:

Ayuh,.... When a free spinnin' prop lands back in the water, at Full Load,....

Ya, 'bout Everything is subject to gettin' Broken... Motor coupler, 'n Aft...
 

Tail_Gunner

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Re: Advice and upate

Re: Advice and upate

Ayuh,.... When a free spinnin' prop lands back in the water, at Full Load,....

Ya, 'bout Everything is subject to gettin' Broken... Motor coupler, 'n Aft...


Take's notes :D.....:faint2: So much for wave hoppin...:facepalm: As obvious as that is it has never even occured to me one time. Man some people's kids.
 

Bondo

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Re: Advice and upate

Re: Advice and upate

Originally Posted by Bond-o
Ayuh,.... When a free spinnin' prop lands back in the water, at Full Load,....

Ya, 'bout Everything is subject to gettin' Broken... Motor coupler, 'n Aft...

Take's notes :D.....:faint2: So much for wave hoppin...:facepalm: As obvious as that is it has never even occured to me one time. Man some people's kids.

Ayuh,.... Glad ya found yer Thought for the day,.... ;) :D

I'm gonna go cut some fire wood,... Good luck with the new barge,... sounds like a Sweet hull...
 
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