how much would it run to turn a 350 into a 383 and also how much power and are they known for any problems

 

not too much. buy a 383 crank, have the 350 block bored .030 over and get some pistons and rods.

im in the proccess of a twin turbo 383 build. i got everythign to build the 383 for $600, but i got a pretty good deal.

 

You might also want to throw in a new cam/lifter/pushrod combo (if you are not on a too tight of a budget), to help with the feeding of your new monster, and possibly heads and a manifold....
-Andrew

 

You don't need to bore the motor out unless the motor needs it. You will need a new flywheel/flexplate that is externally balanced. While you have it out of the car a new cam is also a wise choice. I'd look for used parts. Buying new stroke assembly will run you near 1k bucks.

 

you can get a basic cast 383 crank for ~$200, re-use your 5.7" rods, and get new pistons for ~$200. $400 is about the absolute cheapest it'd be physically possible to do it with.
New bearings, gaskets, seals are obviously needed.
Heads and cam are totally optional.

 

Thats pretty interesting. Where could one find a 3.75" stroke crank for $200? You got my attention now

 

Well, a basic cast iron crank, in 3.75" stroke (but with 350 main bearing sizes) is the same price as a 3.48" stroke one generally, or close.

Ohio crankshaft, has
N3503750 for $195

summit has an eagle one
ESP-103503750 for $189. These two are probably one and the same product, I think ohio usually rebadges eagle stuff. I have ohio rods, and my machinist figured they were probably rebadged eagle stuff. (actually, the eagle one is mentioned as being cast steel, rather than iron)

That would get the job done for up to low 400HP #'s i'd think. You can always upgrade to high end ones...

 

Awesome! Thanks

 

I havent done this, but the general concensus, i think, for these parts, is that they have to be broken in when new. When they are broken in, its for that particular motor. You COULD transfer it to another motor, but the unbalanced stuff creates stress on the moving parts.

I would suggest you go through summit, or buy some "unused" second hand parts. Most places you buy them new, they usually sell them fully balanced. Like it said above, probably around 1k.

The other option is, this is a BIG job, so if you are seriously considering it, chances are you have the budget, so its a good idea to change the entire rotating assembly for new parts. However, if by chance your budget doesnt cover it, you could always just look into setting your 350 aside, and buying prebuilt 383. Would probably save you some time, and probably be around 2-3k. If you look at swap meets, probably a bit less than that.

Good luck man, but its definately a popular option. I cant quantify the power, but im sure everyone who has tried it, has been very satified.

 

Go with the 400

 

Im alos looking to upgrading the 305 to a 383, do you guys know wich year of block is good to start on the build up?

 

It all depends on what you plan on building. If you're looking at just a casual stock bottom end 383 that's all street, a 2 bolt 350 will probably suit you just fine. If you plan on getting forged internals and have big plans, you'll want to go with a 4 bolt or get a 2 bolt splayed. As for "years", if I'm not mistaken, they are all pretty much the same with a few exceptions. It's the aftermarket blocks that are "better".