Offshoreonly.com - SBC to stroke or not...

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If it were me I would splurge for the steel crank internally balanced, and a set of forged pistons. I have seen some pretty scary stuff with those cheap cast stroker cranks (granted this was years ago when they were just starting to come out) so for me I would spend a little extra for peace of mind. And I would never run a hyperutectic (sp) piston in anything. If it is going to be a stocker I will stick with cheapo cast pistons, for anything else I would go forged. Even the cheapo cast pistons are more forgiving if you ever have any detonation.

As for the camshaft... I would go with either this one or the next size up one:
http://www.cranecams.com/product/car...detail&p=24208
That is the cam I have in my 355 with forged flat tops and Dart iron heads and it made 424 hp at 5400 and 445 ft lbs of trq at 4500 at the flywheel with the 320 EFI setup and dyno headers. If you check out the specs you will notice that they match perfectly the specs that are available for the GM Performance ZZ383.

It may be a little more cam than I can use if I keep the Vortec head stock. If I were going a little bigger then this may be a good way to go :)

Quote:

Originally Posted by Lennox60 (Post 3506717)

It may be a little more cam than I can use if I keep the Vortec head stock. If I were going a little bigger then this may be a good way to go :)

Are you buying them new? Not sure I would go that route anyway, but here are some to consider if you are buying new:
http://sdparts.com/details/scoggin-d...nter/sd8060ra2

Just to keep the creative juices flowing Dart SS Iron Eagle heads will work good to. You can get the bare or built up.

Quote:

Originally Posted by fastestbowtie (Post 3508552)

Are you buying them new? Not sure I would go that route anyway, but here are some to consider if you are buying new:
http://sdparts.com/details/scoggin-d...nter/sd8060ra2

Can you elaborate on the Vortec heads? Unfortunately, I am going on a somewhat restricted budget and won't be running a cam that needs more lift than the stock Vortec heads can handle. I may or may not go with new if I can find a decent used set.

At $300/ea from Jegs, they would seem to be pretty good value - http://www.jegs.com/i/GM-Performance...58060/10002/-1

Quote:

Originally Posted by Lennox60 (Post 3503340)

Hi all, I am a first time poster. I just purchased a 1985 CC Scorpion 230SL. The boat is in great shape, with one exception - the Mercruiser 350 is seized. Apparently the boat was not winterized last fall - water is not a great lubricant for bearings...

I will be doing the rebuild myself. I have another 4 bolt main block (if needed) and I also have a good 400 crank. Here's the question; I would like a little more mid-range torque and possibly a litte more top end without sacrificing too much fuel economy - would it be better to simply rebuild the 350 and go with Vortec heads and a bit better cam (Comp Cams or Crane) or would the 383 be the way to go?

I know, it is a loaded question and the first question will be how much do I want to spend - for argument sake, let's say $2500 for parts and machining.

Any input is appreciated.

Thanks,
Len

being that the engine was not winterized you may have a cracked block and or heads and or exhaust manifolds and risers. the engine bearings never are exposed to water so i'm not quite sure why not winterizing the engine would seize it up.

i would definitely go with the 383. i have a warmed up roller cammed small ford in an old searay and i'm running it with an old mercruiser 1 drive (precurser to the alpha) and i've experienced no trouble. as mentioned, watch the hole shots!

the nice thing about small block chevys is that they are cheap to build and there is an endless supply of parts options.

good luck with your build.

Quote:

Originally Posted by vintage chromoly (Post 3508864)

I haven't had a chance to pull everything apart yet to determine all that failed. However, I vacuumed over 2 gallons of water out of the oil pan/block with my Pela pump. My guess is that the engine oil cooler cracked due to freezing and the oil pan slowly filled to the point that there was way more water than oil. When it got to this point, there was lots of water to bearing contact.

I agree with you on the SBC, lots of performance parts out there...

Quote:

Originally Posted by Lennox60 (Post 3503340)

IMO, I would say that whether a 350 or a 383 for a small block, you will need to spin the motor at a higher RPM (5800rpm or so) to gain the speed you are looking for. Just need to select the proper cam operating range and other components to match. Mild cam will limit to around 5100 to 5200rpm. But I just a novice.