When I bought my car it didn't have any shocks in it so I don't know if the stock ones will work or not. For the guys running 3 inch blocks on their 49-52 chevys, what shocks do you have in the rear?
Your local Napa carries Monroe and they have a size chart as well as what ends are on them. Take your static length measurement after you get you blocks installed and what ends you need and go for it. I would say a minimum of 2 inches each way from static height would work great.
For what it's worth, my '52 has 2" blocks with the stock shocks and no problems. I don't think 1" more would be that critical.
Isn't the shock stud on the lower spring plate? So the relationship between the two shock mounts is unchanged? So no change in shock is required? If your lower shock stud is above the block, move it to the spring plate below the block.
You can find out what the OE shock dimensions are- eye-to-eye fully extended and compressed. then subtract 3". here's how I did mine: http://orphanyears.blogspot.com/2009/02/shock-less-traveled.html Here's the chart:
dearched leafs, air jackers in the rear together w/3.5" lowering blocks. Shoks from a 65/66 Nova fitted great! okay i did also have rewelded lower spring plate, all to get away from the "scrubline"!
yes, stock shocks work fine, my 52 sled has three inch blocks and its a bumpy ride but still room, i cut the bumpstops and its not low enough, i will eventually switch to four inch blocks