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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

351 block

  • Thread starter Thread starter aleborjas
  • Start date Start date Jan 11, 2007

aleborjas

New Member
Sep 11, 2005
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0
Jan 11, 2007
#1
  • Jan 11, 2007
  • #1
hi, i want to know how much HP and torque a 351 block can support stroked to 408 with good studs and main caps and which is the best one and how can i diff.. one from an other?
 

aleborjas

New Member
Sep 11, 2005
610
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0
Jan 12, 2007
#2
  • Jan 12, 2007
  • #2
anyone?
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Jan 12, 2007
#3
  • Jan 12, 2007
  • #3
I can't post more detail right now, but check my site.

I have a writeup on the 351w blocks, and how they are different.


Maybe I can post the writeup when I get home.


jason
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Jan 12, 2007
#4
  • Jan 12, 2007
  • #4
well suffice it to say they will handle more then the 302 blocks. Reliable numbers for 70-74 year blocks would be 550+ hp, I doubt going past 700hp would be a good idea specially if you were going to turn high rpms. those are the strongest blocks. well factory anyways. obviuosly svo and other aftermarcket blocks are stronger.
 

Modular2v

Founding Member
Jun 30, 2002
3,222
23
99
oklahoma
Jan 12, 2007
#5
  • Jan 12, 2007
  • #5
actually i think 69-74 are the strong blocks. They support more than a late model block (302 or 351, 5.0 or 5.8) If you look at the difference in the main caps you will see why.....its a clear night and day difference pluse the older blocks had a higher nickel content thus making them stronger. I would not go past 600 hp
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Jan 12, 2007
#6
  • Jan 12, 2007
  • #6
yes 69-74 blocks are the strong ones but 69 block is in a class of its own since it's deck hieght is less. Pain in the butt to buy specialty parts for a one year block. stick with 70-74 blocks for the strong ones.
 

Modular2v

Founding Member
Jun 30, 2002
3,222
23
99
oklahoma
Jan 12, 2007
#7
  • Jan 12, 2007
  • #7
86bluecobra said:
yes 69-74 blocks are the strong ones but 69 block is in a class of its own since it's deck hieght is less. Pain in the butt to buy specialty parts for a one year block. stick with 70-74 blocks for the strong ones.
Click to expand...

yeah didnt think about the deck height differences......i have a 69 block sitting in the shop too
 
F

FullAuto

Founding Member
Aug 29, 2002
157
0
16
Midwest City, Ok
Jan 12, 2007
#8
  • Jan 12, 2007
  • #8
'70 has the same deck height as the '69. And what kind of specialty parts are you guys running for the shorter blocks?
 

vristang

15 Year Member
Mar 31, 2005
4,933
101
124
Seattle
Jan 12, 2007
#9
  • Jan 12, 2007
  • #9
From my site...



351w Casting Numbers
The casting numbers are on the passenger side near the starter location. You will have to turn the block upside down, or use a mirror to see them.

The year will be designated by the first 2 digits of the casting number.
The first digit is the decade and will be a letter. C=1960's, D=1970's, E=1980's, and so on. The second digit will be a number and specifies the year of the decade. Some examples follow:
D1=1971
E9=1989
F4=1994

For more info on how to identify various Ford engine blocks check out the following link…
http://www.fordification.com/engineID.htm


Getting Into the Nitty-Gritty

The 351w Engine Block -
69-70 - High Nickel content and thicker main webs (These are the only Production Ford 9.480" Deck Height 351w blocks)
71-74 - Reduced Nickel content thinner main webs (71-up had 9.503" Deck Height)
75-91 - Reduced main web thickness
92-On - Lifter Bores were lengthened to accept roller lifters

There were some 351w Mexican blocks as well. The early versions of which are desirable due to their beefier castings and higher nickel contents. A Mexican block can be identified by the useless looking knobs cast into the block on either side of the timing cover, and an “Hencho en Mexico” cast into the lifter valley. Mexican blocks were supposedly used on some US vehicles, but they are a fairly rare find.
 
8

86bluecobra

Advanced Member
Dec 20, 2004
4,265
12
69
B.C. Canada
Jan 13, 2007
#10
  • Jan 13, 2007
  • #10
FullAuto said:
'70 has the same deck height as the '69. And what kind of specialty parts are you guys running for the shorter blocks?
Click to expand...

lol my bad. 69 and 70 blocks require different intakes. i could be wrong but i believe also dizzy's. Its not as easy as going to a swap meet and picking up any old vic jr and installing it. You end up looking for block specific. kinda a pain in the butt to me anyways.
 
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