small block in an 85 Sea Ray Seville open bow

Chris_94_Sprint_TX

Chris_94_Sprint_TX

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Can a Small block say 5.7L or 305 fit and be practical in the 18.5 ft bow rider. I know some of them have 4.3L in them as a factory upgrade. I have been told yes but I have seen just as many responses saying no. I know with the right amount of money anything can be done but what I am asking is can it bolt right in with a Bravo III drive but any Bravo drive should be sufficient or are the alpha drives just as strong or should bravos be used with small blocks. This is more a curiosity question than anything.

Chris
 
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HT32BSX115

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Re: small block in an 85 Sea Ray Seville open bow

88_searay_seville said:
Can a Small block say 5.7L or 305 fit and be practical in the 18.5 ft bow rider. I know some of them have 4.3L in them as a factory upgrade. I have been told yes but I have seen just as many responses saying no. I know with the right amount of money anything can be done but what I am asking is can it bolt right in with a Bravo III drive but any Bravo drive should be sufficient or are the alpha drives just as strong or should bravos be used with small blocks. This is more a curiosity question than anything.

Chris
Click to expand...

Howdy,

My previous boat (A 66 MarkTwain 18' V-Sonic) was offered with the 110, 120, 150, 190, 200, 310hp engines. The 110 was a 4cyl engine with a Merc I drive...

The 310 was a 409 Chev engine with the Merc II drive.

If you look at the placard on your boat, it should indicate the max HP the boat could be offered with... Many 18' boats were offered with various sized V-8s over the years.
 
Nivekt

Nivekt

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Re: small block in an 85 Sea Ray Seville open bow

I have a '79 cobalt 18' trihull with a SBC 350 in it. Takes a little to get on plane with a couple people in the back because of all the weight back there but otherwise does fine.
 
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TilliamWe

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Re: small block in an 85 Sea Ray Seville open bow

My father installed a 5.7 V8 in a 1989ish 19' Seville in place of a 4.3. He had to move the engine cover a bit and the gas tank was actually in the way. He had to "massage" the tank to miss the damper pulley and he had to change a fuel line or two at the water/fuel separator. Bravo drive requires changing EVERYTHING. Engine coupler, transom plate, gimbal, everything from the flywheel to the prop.

No real need for a Bravo drive. Unless you are really beefing up a 5.7, an Alpha will handle 300hp all day long. Just don't jump the boat out of the water on wakes/waves. Big time $$$$$ to put in a Bravo.
 
Chris_94_Sprint_TX

Chris_94_Sprint_TX

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Re: small block in an 85 Sea Ray Seville open bow

I was more curious than anything. I have the 4cyl in mine right now and it seems like a strong running boat with it and after I replace the prop shoud run a lot stronger. I think trying to run a 300HP 5.7L if its close to the power limit of the drive wouldn't be reliable. I was thinking Bravo only for the added strength. but I like the dual prop of the bravo III but the cost is really up there and I think putting an $18000 motor and stern drive in a $1500 29 year old boat might be a little out there.

Chris
 
Bondo

Bondo

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Re: small block in an 85 Sea Ray Seville open bow

88_searay_seville said:
I was more curious than anything. I have the 4cyl in mine right now and it seems like a strong running boat with it and after I replace the prop shoud run a lot stronger. I think trying to run a 300HP 5.7L if its close to the power limit of the drive wouldn't be reliable. I was thinking Bravo only for the added strength. but I like the dual prop of the bravo III but the cost is really up there and I think putting an $18000 motor and stern drive in a $1500 29 year old boat might be a little out there.

Chris
Click to expand...

Ayuh,... But Dreams are where Fun comes from,...... ;)
 
Chris_94_Sprint_TX

Chris_94_Sprint_TX

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Re: small block in an 85 Sea Ray Seville open bow

Well said Bond-o. But I'd have to my dream would be a 35 foot cuddy cabin with twin diesels twin BB with a switchable thru hull like captains call. But, this is unattainable on my current income (full time student in a BS-IT program for information systems security and cyber security) but one day and it will probably be a Sea Ray too.

Chris

A little off topic buti is it possible to change my username from 88 to 85 without creating another account?
 
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chimmike

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Re: small block in an 85 Sea Ray Seville open bow

TilliamWe said:
an Alpha will handle 300hp all day long.
Click to expand...

Is this true? Got a 5.0 with my Alpha in a '91 and i'd like to massage it a teensy bit once it's running smooth...but nothing major, maybe intake manifold and carbed to match
 
Bondo

Bondo

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Re: small block in an 85 Sea Ray Seville open bow

chimmike said:
Is this true? Got a 5.0 with my Alpha in a '91 and i'd like to massage it a teensy bit once it's running smooth...but nothing major, maybe intake manifold and carbed to match
Click to expand...

Ayuh,.... A 305 will never hurt an Alpha, unless yer doin' somethin' Stupid,....
 
Chris_94_Sprint_TX

Chris_94_Sprint_TX

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Re: small block in an 85 Sea Ray Seville open bow

Will a 305 fit in place of a Mercruiser 140?

Chris
 
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chimmike

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Re: small block in an 85 Sea Ray Seville open bow

Bond-o said:
Ayuh,.... A 305 will never hurt an Alpha, unless yer doin' somethin' Stupid,....
Click to expand...

I can do a lot of stupid things with motors. Don't make me prove it! hahahaha.
 
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chimmike

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Re: small block in an 85 Sea Ray Seville open bow

HT32BSX115 said:
Don't forget pictures! We LOVE pictures!
Click to expand...

I could show a picture of the stupidity I did with my daily driver. 450whp turbocharged 2.3L 4banger. But I won't do that to the boat. 40-50mph is plenty fast on the water.
 
Chris_94_Sprint_TX

Chris_94_Sprint_TX

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Re: small block in an 85 Sea Ray Seville open bow

How much wider is the 4.3L V6 that was offered as an upgrade than the 140?

Chris
 
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chimmike

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Re: small block in an 85 Sea Ray Seville open bow

the vee motors are a bit wider than an inline 4. I would imagine the 4.3 is pretty similar in width do the v8's.
 
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TilliamWe

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Re: small block in an 85 Sea Ray Seville open bow

chimmike said:
...I would imagine the 4.3 is pretty similar in width do the v8's.
Click to expand...


Yep, the phrase "nearly exact" comes to mind. Since they are the same block, minus two cylinders!
 
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