Insert bearings for a 221 block?

J

Juergen

Well-known member
I would like to rebuild a 221 block using insert bearings using perhaps 49 Ford crank and rods. How much work is involved? Can you line bore the block to accept insert bearings using 49 caps? Is it cost prohibitive with respect to finding/staying with full floating bearings?
 
You don't mention which particular 221 block you're dealing with, but possibly it could be more cost efficient to grind the main journals of the later crank down to suit the block. This would entail widening the centre bearing journal also. And you'd need to convert the rear main cap to suit the later seal instead of the existing double slinger. The conrods won't pass down the smaller bore. Heck, if you're going to all that work might as well stroke the crank while you're at it! My opinion, Brian
 
The 49-53 crank will bolt right into the 39-48 block. You can buy the rear seal retainer for the 39-42 block and cap. Main brg bore size is the same 39-53. Use the main bearings that goes with the block. If you useing a 37-early 38 block it's a whole new ball game. You have to turn the 8BA mains down .100 Walt
 
I should have mentioned I would like to do this to a 1937 21 stud block and yes go for a stroker crank. Walt, is the whole new ball game merely truning down the mains?
 
Yes, turn down the mains and I believe Red's Headers sell a rear seal adapter. There is a little machine work to bolt the retainer to the rear cap. You can bore the 37 engine .125 to 3-3/16 and use the 8BA pistons, then the 8BA rods will go through the bore. If your going to use the 3-3/4 crank, to me it's a waste of time and money. If your going to do this project use the 4in. crank. Walt
 
Juergen: To use Reds rear main kit you need to have the crank rear ridge that rides in the oil slinger ground down when you have your crank work done. The rear main cap can then take a rope seal. We did this on my 35 221. I have some picture somewhere. email if your interested. Thanks Dave/Green Bay
 
Last edited:
Walt ,will the LB engine bore out to 3.3/16.I have a rusty one,and the 4 in crank would make for a good engine for the 34.
Lawrie
 
I should have mentioned I would like to do this to a 1937 21 stud block and yes go for a stroker crank. Walt, is the whole new ball game merely truning down the mains?
Click to expand...

The 37 HAS inset bearings. I did this very same motor for my Cabriolet but I went with a 4 in merc crank. Be prepared to spend A LOT of money to fit that crank and get the special custom pistons you are going to need to do it. You will also need to change the rods.

If I had to do it again... I would rebuild it stock except I would do the crank work for the oil seals, they were definitely worth it!
 
Lawrie, I wouldn't bore the 36LB .125 to 3-3/16, I only recommend .060 the walls are pretty thin in those early blocks. I built an LB engine a few yr's ago, the gye brought in 3 blocks before I found one I could use and I had to sleeve 3-4 holes. The 37 up will go .125 with no problem. Walt
 
You must log in or register to reply here.
Back
Top