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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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How Much Power can a 351 handle

  • Thread starter Thread starter NewToFord
  • Start date Start date Nov 21, 2008
N

NewToFord

Member
Oct 7, 2008
318
1
19
CT
Nov 21, 2008
#1
  • Nov 21, 2008
  • #1
I want to start my blown 351 build in a few months, and I was wondering how much power the 351 can handle. I am hoping for about 600 rwhp. Will it hold up to this? I am talking about any 351w from 1970 to present.
 

BK_CAULEY

it's built for speed not longevity, woman
Dec 26, 2006
0
10
49
Thomasville, ga
Nov 22, 2008
#2
  • Nov 22, 2008
  • #2
there is so not enough info in this thread. whats the combo gonna be like? comp ratio and so forth.
 
N

NewToFord

Member
Oct 7, 2008
318
1
19
CT
Nov 22, 2008
#3
  • Nov 22, 2008
  • #3
I'm not exactly sure of all the details yet, because the motor has yet to be built. Probably 8.5-9.5 compression, victor jr heads victor intake, custom tuned pcm. And a blower on top making 15 or so lbs of boost. I want this car to run on 93 octane.
 

BK_CAULEY

it's built for speed not longevity, woman
Dec 26, 2006
0
10
49
Thomasville, ga
Nov 22, 2008
#4
  • Nov 22, 2008
  • #4
with a a conservative tune and no extremem timing or race fuel it can handle aorund 600 but thats the limit it on it.
 
B

bentley429

Banned
Nov 25, 2004
528
3
0
Connecticut
Nov 22, 2008
#5
  • Nov 22, 2008
  • #5
Depends on the year of the block. Some have been pushed HARD. Read about some 800+. 600-700 is safe in my mind.
 
I

irish

New Member
Oct 18, 2006
168
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0
Florida
Nov 23, 2008
#6
  • Nov 23, 2008
  • #6
If you are worried about it go with an early block, a 1969-70 would be ideal. Thats as strong as you can get before stepping up to aftermarket. A 71-74 would be ok to and they are abit cheaper then the 9.48 blocks. If you look in the classifieds I'm sure you will find some.

Matt
 
5

57fairlane

New Member
Apr 2, 2005
560
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0
Oakwood, GA
Nov 24, 2008
#7
  • Nov 24, 2008
  • #7
just to add . . .

the 71-74 blocks, when converted to 4-bolt mains I have seen go 125+ in the 1/8 figure around 800hp or so.

I built a 84 block using some junk (393 with scat crank, stock rods, probe pistons) and it just made over 600rwhp with a t76 on pump gas.
 
N

NewToFord

Member
Oct 7, 2008
318
1
19
CT
Nov 24, 2008
#8
  • Nov 24, 2008
  • #8
thanks for the help guys. I would not be better off going with one of the new Boss 302 blocks would I? I know it would be less cubes, but is it any stronger than a 351? By the way the 351 was gonna be stroked to a 393.
 

FastDriver

I was uncomfortably high & wearing a helmet
SN Certified Technician
Sep 5, 2001
6,079
2,680
224
Vass, NC
Nov 24, 2008
#9
  • Nov 24, 2008
  • #9
As long as the rotating assembly doesn't come apart, you're not going to break a new boss block. Yes, it is stronger than a 351, but that doesn't mean that it's better for you. FMS says you shouldn't go more than 0.125" over bore, and with a 3.4" stroke, you're still only coming out to 364 cubes... So, if you're going to stay naturally aspirated, I'd say you're better off with the 393, because you won't have to worry about block strength until you get over 700hp on a 351 block. However, if you have forced induction aspirations in the future, then you really should think about going aftermarket. Why not spend a few hundred extra, though, and get yourself a 351 iron eagle from Dart? Then you've got the best of both worlds.

Chris
 
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