Thread: 350 Build Questions

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Building a SB 350, using a 305 crank. Do I need to get the crank rebalanced? If so, do I install it first, then take it to a machine shop?

Also, am I going to need any special connecting rods or just 350 rods? I'll be buying all new pistons, rods, etc.
Thanks

Counterbalancing on the 305 crank is different from the 350 crank. Have the whole mess internally balanced. Run-of-the-mill 350 rods will work fine. Try to find pistons with the longest compression height dimension (pin center to crown) so you won't have to take so much off the block to get the squish right.

What do you mean by take some off of the block?
What excactly does the machine shop do when they internally balance it? Do they do this after the rotating assembly is in place?

What Richard was trying to help you with is to get the proper pistons because the generics have a bad tendency to stay deeper in the hole than prefered. If the pistons are down in the hole deeper than is acceptable, the squish will not be enough for effective compression and flame travel. therefore the block should be milled. Get the right pistons and you won't have to go through all that.

What excactly does the machine shop do when they internally balance it? Do they do this after the rotating assembly is in place?

Part of the balancing process is to ensure that all rods and pistons are exactly the same weight. That is done prior to assembly.

Thanks, does the 305 crank give it a shorter stroke?
And would I assemble the rotating assembly before taking it to the shop? or do they balance it out of the block?

Oh, nevermind. Thanks

Same stroke, 3.48"
Don't assemble anything. Take the whole mess to the shop.

Great, thanks everyone!

I just went through this very same hassle. You'd be better off to spend $150 and get a brand new 350 crank from Speedway.............