mercruiser 165 (chevy inline 6 250) to mercruiser 4.3

[gcurrence]

i tryed searching to see if this has been discussed before but im not a good searcher so i only made it so far, so I thought i would ask, I have a 1976 22-2 cuddy with the mer. 165 inline 6, the 165 is worn out and its time to be freshened up, im going to spend some good money on a mechine shop and gasket kits and everything eltes that a fresh motor needs, I have been tolds that the bell housing from my 165 will fit the 4.3 v6, i dont have a problem moving the front motor mount but how about the throdle controls and the exhaust connections, im not in need a power gains, though it wouldnt hurt, the 165 is easy to work on, how about the 4.3? has anyone done this with positive outcomes? thanks alot for the help,

[GoneFission]

I would stay with the inline 6.  An inline 6 is an inherently balanced engine, whereas the 4.3 has to use some work to make it somewhat smooth.  Balance is better on the I6 and everything will fit.  Go to a 5.7 V8 if you want to change...

[gcurrence]

are the throdle cables the same? does the exhaust port though the transom need to be replace sence there will be 2 manafolds or do they meet and go though 1 exhaust port, does the transom mount for the 165 work with all mercruiser blocks? i guess those are the main things i would be concerned about, everything eltes would be wiring, fuel, and outdrive ratio, i have the 1.65 now i think i need to gear it or 1.50 if i put the 5.7 in,thanks

[GoneFission]

are the throdle cables the same? does the exhaust port though the transom need to be replace sence there will be 2 manafolds or do they meet and go though 1 exhaust port, does the transom mount for the 165 work with all mercruiser blocks? i guess those are the main things i would be concerned about, everything eltes would be wiring, fuel, and outdrive ratio, i have the 1.65 now i think i need to gear it or 1.50 if i put the 5.7 in,thanks

Throttle cable might change depending on how tight it is now.  
You would need a Y adapter to connect the twin exhaust outlets together into a single.  
Outdrive/transom should be the same, but you may need a different driveshaft.  
Outdrive ratio can stay the same, just change prop pitch to make up for any difference between your 1.65 and a 1.47 that would probably be the preferred ratio.  

You might find a deal out there somewhere:
http://www.ebay.com/itm/5-7-Mercruiser- ... 3a736851e9

Got the bucks?  Buy the whole package new and bolt her in:
http://www.ebay.com/itm/NEW-Mercruiser- ... 5d3154edc3