38 swap to 43

"is it possible to swap out th

"is it possible to swap out the 3.8 in my dynasty to an early model 4.3 2pc seal engine? or could i find an automotive 4.3, install a marine cam, and drop it in my boat? if not where can i find an engine? my block and manifolds are cracked!"

"I have remanufactured 3.8 sho

"I have remanufactured 3.8 short blocks.
A lot of 1980-84 Chev Monte carlo, Malibu elcamino etc had the 229 as well but many had the corporate buick 231.you could do a 4.3 but would need a 4.3 marine distributor and nott sure what else.
The 2 pc 4.3 was a 1 year only engine."

i was told i could use the 3.8

i was told i could use the 3.8 distributer. if not could i purchase an aftermarket distributer for marine use? can i buy an automotive 4.3 2pc seal crate engine and swap cams? how much for the block and exhaust mans? thanks for the help.

"you were told wrong about usi

"you were told wrong about using a 3.8 distributor in a 4.3 -the firing will be 12 degrees advanced on 3 cylinders, and 12 degrees retarded on the other 3 cylinders. It will actually run, but not properly.

but yes, you could buy a new 4.3 distributor.
You will also have the option of buying a fully electronic ignition system for a 4.3, whereas the 3.8 only has a points version.

A 4.3 or a 3.8 long block are both around $1500 from any reputable rebuilder.

Do they make a crate 4.3 with a 2 pc rear main?
I haven't seen one, but maybe they do....
A marine cam for a 4.3 runs about $200 with lifters.
The manifolds (Osco) go for about $1000 a set with risers.
If you have selectrim, Osco manifolds are your only choice as all others will not clear the selectrim rams.
The same Osco manifolds fit the 3.8 or 4.3
The Osco's are centre riser design so some additional plumbing of marine exhaust hose will be required to connect them to the intermediate.

If you stay 3.8, you can probably reuse your cylinder heads & camshaft if they look ok and reuse your ignition system and save around $1000 compared to a 4.3 conversion. That savings buys the manifolds.
Not sure if there would be any headaches getting the OMC belt tensioner and alternator brackets onto 4.3 block/heads...the holes might be slightly off... could check the 1985 OMC 4.3 parts book vs. 1985 3.8 for that detail

A 4.3 will get you an additional 5 or 10 horsepower over the 3.8

If you are interested in a remanufactured 3.8 short block, email me."

"ok, now I have to re-think.

"ok, now I have to re-think.
I don't understand the distributer running a total of 36deg off I thouht the cam chose the timing? maybe i'm wrong, not familier with marine components! how much for the block? I found a 2pc 4.3 reman for under 2k but I'd have to use some of my 3.8 parts (flywheel,int. man,exh. man.,etc.) I know that the 4.3 is more common on parts than the 3.8. thats my main reason for a swap! i also know in the auto world the chevy 3.8 is based off a 305(bore,stroke) and 4.3 the 350. is it not the same on marine use? i'm just not that familiar with inboards. thanks for your help!!!"

"car, truck, boat or tractor..

"car, truck, boat or tractor... the camshaft opens the engine's valves.

The distributor times the spark. And a 4.3 requires the spark at different times than a 3.8 due to the offset crank journals and "semi-even" firing order of the 3.8
The 4.3 is an even-fire V6. 120 degrees X6 = 720 degrees.
The 3.8 fires at 108, 132, 108, 132, 108, 132

I thought your exh. manifolds were toast.

The factory 3.8 manifolds will not fit 4.3 heads.

The Osco brand center riser manifolds will fit either 3.8 or 4.3 heads.

NORS 3.8 short block $999 + ship. .030" over - new pistons, std. main and rod brgs. , brass core plugs. Everything magnafluxed, honed, crack checked and returned to factory spec.
Block is in the factory OMC shipping crate."

gotcha! now it makes since. i

gotcha! now it makes since. i found exh. mans. for $200 is why i asked!
I'm still tossing on 3.8 or 4.3. horsepower not much concern to me versus the availability of parts as time goes on. where could i find a good distributer for a 4.3 that would work with my wire harness. again i really appreciate the help!