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Whats The Best 347 Block?

  • Thread starter Thread starter 65FBE2
  • Start date Start date Mar 1, 2010

65FBE2

Member
Mar 8, 2007
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Minnasnowta
Mar 1, 2010
#1
  • Mar 1, 2010
  • #1
I have a 347 that has a terminal oil leak. The engine builder suggests a different block. I currently have a D1 block. I need to get something at the junk yard as I can not afford a Mexican or Boss block. What year did Ford start with the one piece seal? If I use a roller block, can I use a solid flat tappet cam? Reason is I need to save money and use the parts I currently have. It is a 5 speed tranny. I heard at some point Ford stopped putting the boss on the block for the clutch equalizer bar. How do we get around this?
 

silver66pony

New Member
Dec 1, 2009
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0
Mar 1, 2010
#2
  • Mar 1, 2010
  • #2
My 351 w block is a 1984 it did not have a hole for the z bar i had to drill and tap it out works just fine now
 

coolblue65

Founding Member
Jul 26, 1999
1,224
2
39
Algonquin, IL
Mar 1, 2010
#3
  • Mar 1, 2010
  • #3
There is also a small bracket you can use instead of drilling and tapping the hole, I used it on my 347.
 
1

10secgoal

Active Member
Dec 1, 2003
2,801
3
49
San Diego
Mar 1, 2010
#4
  • Mar 1, 2010
  • #4
Can't remember, but someone makes a bracket that bolts on with the tranny to adapt the stud for the Z-bar.
 

65FBE2

Member
Mar 8, 2007
283
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17
Minnasnowta
Mar 1, 2010
#5
  • Mar 1, 2010
  • #5
What year did they start with the one piece seal? If anyone is interested, I have a set of RHS 200 heads for sale CI 64cc .560 max lift New in box
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Mar 1, 2010
#6
  • Mar 1, 2010
  • #6
Are you saying the main saddles are cracked? I thought the roller blocks were the weakest.
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
Mar 2, 2010
#7
  • Mar 2, 2010
  • #7
Look for a D8VE 302 block. This one's thicker all over like the Mex block, just has the smaller std main caps of the regular blocks. Not a big deal if you're going to use a main girdle anyway. If you're going to a roller block, skip the 85 castings and look only at the 86-2001's.
 
J

JR4 Motorsports

New Member
Aug 5, 2009
18
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Carmel, NY
Mar 2, 2010
#8
  • Mar 2, 2010
  • #8
What is making the oil leak "terminal"?
 

65FBE2

Member
Mar 8, 2007
283
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17
Minnasnowta
Mar 2, 2010
#9
  • Mar 2, 2010
  • #9
"Terminal" only in that I have replaced it for the third time in the car and can not fix it so I pulled the motor to find this problem. Could it be the crank? Are the stroker cranks the same or is there a differents in the rear main area? Slinger?
 

65FBE2

Member
Mar 8, 2007
283
0
17
Minnasnowta
Mar 2, 2010
#10
  • Mar 2, 2010
  • #10
Just took the motor apart and found nothing that looks like it is causing the problem BUT. I used a cast crank from CHP and I have no ideal why this happened. The end play was way over the limit. So I removed the thrust bearing cap and found the crank severly worn. The motor only has 2000 miles on it. I don't think this was the cause of the leak, any ideals as to what happened?
 
D

D.Hearne

New Member
Sep 29, 2000
11,730
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0
south louisiana
Mar 3, 2010
#11
  • Mar 3, 2010
  • #11
65FBE2 said:
Just took the motor apart and found nothing that looks like it is causing the problem BUT. I used a cast crank from CHP and I have no ideal why this happened. The end play was way over the limit. So I removed the thrust bearing cap and found the crank severly worn. The motor only has 2000 miles on it. I don't think this was the cause of the leak, any ideals as to what happened?
Click to expand...

The leaking seal can and most likely is caused by the walking crank. Looks like you're needing both a block and crank to start over with. And if you're running an automatic trans, check to see if there's too much presssure in the torque converter, that'll force the crank against the thrust bearing and cause premature wear.
 
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