350 sbc

can I use the same 6 inch rod piston combo from a 3.48 crank on a 3.5 crank? 350 bored .030, otherwise untouched

Some pistons were made so you could do that they had a compression height of 1.250 instead of 1.260. If the block has already been decked for the 3.48 stroke you will either have to get a .010 thicker head gasket or a different block.

i have milled the top of flat top pistons to 0 deck before if the piston is thick enough , only seen a few ultra light weight pistons that you couldn't , or probably shouldn't .

stock block, except the bore, not ultra light pistons. Actually i want to use the 6 inch rods from the stock steel 3.48 crank 355, put a set of pistons designed for 6 inch rod that are for a 360, and a 3.5 crank. Why? so I can get rid of the pistons and get them off the shelf

if your buying the correct piston to start with, then you should be fine, you can use 6in rods on either crank, if you put 3.48 pistons on 3.50 crank, there gone come out of block .010 to 0.20 in could be cut to 0 deck if your rules require this, if your rules dont , then use thicker head gasket, now if you use pistons for 3.50 crank on 3.48 crank, then your pistons are gone be in the block .010 to .020 in and you could deck the block to 0 deck. I personally like to leave the pistons .005 in the block. sounds to me like your going to buy the correct pistons anyway and you should be fine, good luck....

You are only coming up .010 and going down .010 , .020 from 3.48 to 3.50 . no way would I worry about it.

the 3.5, 6in pistons were given to me. hate to waste them. might just bore block and leave 3.48 crank. cheaper.

It all depends on the deck height with ranges around 9.025 on the stock block. 9.000 is the blue print dimension but most stock blocks hover around the 9.025 mark. Assuming the block is 9.025 the 3.5 stroke crank will work just fine leaving the piston about .020 in the hole and with a typical gasket of .041 you'll have plenty of room. You have a about .020 min of piston to head clearance to work with.

perfect, thanks for all the response