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302 BOSS BLOCK VS MAN O WAR

  • Thread starter Thread starter TOM B
  • Start date Start date Nov 11, 2007
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TOM B

20+ Year Stangneter
Nov 15, 2002
872
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Harrisburg Pa
Nov 11, 2007
#1
  • Nov 11, 2007
  • #1
In my 65 stang Im thinking about changing the block.. For $2395 The Man O War 302 block or the new Boss 302 block at $1700.
Which block is stronger and how much HP will they hold up to.
Can I add NOS And a blower to each. I was told that the Man O War is a harder cast iron But who has one I dont know.
I now have a Mexican 302 in my car now with a Paxton Novi 2000 at 14 psi and a 200 shot NOS that was never lit because I dont want to see the thing explode!
Also with that much boost I cant stop a nagging rear seal leak, thin I should run a vacuum pump?
 

rbohm

Founding Member
Apr 12, 2002
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tucson,az
Nov 11, 2007
#2
  • Nov 11, 2007
  • #2
the man-o-war block is much stronger than the new boss 302 block is. it is also capable of more cubic inches that the new boss block is.

yes you can add the blower and the nitrous to both blocks.

as for running a vacuum pump, it has been shown on the dyno to make power. on a big block chevy a vacuum pump helped make an extra 35hp on the dyno.
 

classic boost

Founding Member
Feb 3, 1999
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canton, oh
Nov 11, 2007
#3
  • Nov 11, 2007
  • #3
TOM B said:
Also with that much boost I cant stop a nagging rear seal leak, thin I should run a vacuum pump?
Click to expand...

boost shouldn't be causing your leak. if it is, then you need to vent your crankcase better.

the man 'o war will hold more power then the new boss, but the boss will hold more power than most people will make. that $700 you save will go a long way for other parts.
 
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10secgoal

Active Member
Dec 1, 2003
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San Diego
Nov 12, 2007
#4
  • Nov 12, 2007
  • #4
The boss block can't really go farther than .060 over, and the skirts are shorter than on stock blocks. So be careful if you're gonna stroke. But that block is still a good alternative to stock for sure.
 
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holcombford1

New Member
Oct 30, 2007
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wilmington,nc
Nov 12, 2007
#5
  • Nov 12, 2007
  • #5
The man-0-war is stronger but,for your app the boss would be fine.You can go up to a 4.125 bore with the boss block.
 

SoCalCruising

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#6
  • Nov 12, 2007
  • #6
10secgoal: why do you say .060" over is about it on a new Boss?
 

brianj5600

Active Member
Sep 19, 2003
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Nov 12, 2007
#7
  • Nov 12, 2007
  • #7
I think he was thinking 69-70 boss block.
 
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180 Out

Member
Jul 23, 2005
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#8
  • Nov 12, 2007
  • #8
The bore centers of both blocks are the same. Both blocks have siamesed water jackets. Both blocks can go to 4.185". That's 60 over if you start at 4.125", but it's 180 over -- three times 60 over -- if you start at 4.000".
 
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10secgoal

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#9
  • Nov 12, 2007
  • #9
SoCalCruising said:
10secgoal: why do you say .060" over is about it on a new Boss?
Click to expand...

Because my machine shop has had a rash of them since they came out. And they said it starts to get a little thin for street driving at .060. Not that it can't go farther. You can do a 347 also, but the pistons are deadly close to being out of the bottom. That shop won't even assemble a 342 in the new blocks because the skirts are so short.They have another over there right now. i'll see if I can steal some bore thickness measurements from them
 
T

TOM B

20+ Year Stangneter
Nov 15, 2002
872
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Harrisburg Pa
Nov 13, 2007
#10
  • Nov 13, 2007
  • #10
If the new boss block has shorter skirts than the older blocks Then WHY buy one.
If this is true than why would ord even bother to make the new boss block socalled better and stronger than the old block,, this dont make sense to me.
 
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Rookie71

Member
Jul 25, 2006
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Nov 14, 2007
#11
  • Nov 14, 2007
  • #11
At this point, why even go the BOSS block route? Why not just go with the known quantity you are getting with a Dart Sportsman block?
 
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10secgoal

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Dec 1, 2003
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Nov 14, 2007
#12
  • Nov 14, 2007
  • #12
Because there are some people that want a little more than a stock block can handle, but don't need a 2500 block. I personally wouldn't buy one because you can't go .125 over
 

Hack

15 Year Member
Mar 23, 2004
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Nov 14, 2007
#13
  • Nov 14, 2007
  • #13
TOM B said:
If the new boss block has shorter skirts than the older blocks Then WHY buy one.
If this is true than why would ord even bother to make the new boss block socalled better and stronger than the old block,, this dont make sense to me.
Click to expand...

I agree. It doesn't make any sense to me either. That's why I would have to see proof before I believe that Ford would make that mistake. No offense meant to anyone on this forum...
 
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Rookie71

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Jul 25, 2006
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Nov 14, 2007
#14
  • Nov 14, 2007
  • #14
10secgoal said:
Because there are some people that want a little more than a stock block can handle, but don't need a 2500 block. I personally wouldn't buy one because you can't go .125 over
Click to expand...

Now I'm even more confused. The subject is comparing the Man'o'war 302 block vs. the new FRPP Boss 302. the Man'o'war has 4 bolts on 1,2,3,4,5 while the Boss is 4 bolt on 2,3,4. The Dart sportsman block which is also a 4 bolt 2,3,4 wasn't mentioned but seems like a more logical comparison to the Boss 302. As far as price, using www.adperformance.com as a reference.

Boss 302: $1775
Man'o'war 302: $2275
Dart Sportsman 302: $1999

 
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10secgoal

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Dec 1, 2003
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Nov 14, 2007
#15
  • Nov 14, 2007
  • #15
ADperformance is a great place to get it. They look like they have gone down quite a bit. But they've always had good prices.
I'd personally stick with the dart because of less hassle trying to fit a pan to a block with 4-bolt on mains 1-5.
 
T

TOM B

20+ Year Stangneter
Nov 15, 2002
872
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Harrisburg Pa
Nov 15, 2007
#16
  • Nov 15, 2007
  • #16
I have a original 302 Boss block in the basement but I dont want to use that block. I didnt know that Dart also made a 302 block so I done some research and found out that Ford crate motors call there Block a sportsman and is used on three of there lower HP engines but on ther High HP 347 engine they use the new Boss Block, SO is what Ford calls the sportsman Block one of Fords blocks or a Dart Block,,, HMMmmmm,
 

NasaGT

Founding Member
Sep 19, 2002
1,993
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Virginia
Nov 16, 2007
#17
  • Nov 16, 2007
  • #17
I thought the new Boss block has a 4.125" bore capacity, finished at 3.990" to 3.995" rough bore. So you can go .125 over.
 

CochinoFilipino

Founding Member
Jan 14, 2002
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CA
Nov 16, 2007
#18
  • Nov 16, 2007
  • #18
NasaGT said:
I thought the new Boss block has a 4.125" bore capacity, finished at 3.990" to 3.995" rough bore. So you can go .125 over.
Click to expand...


That's what their site says http://www.fordracingparts.com/parts/part_details.asp?PartKeyField=9085
 
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10secgoal

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Dec 1, 2003
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Nov 16, 2007
#19
  • Nov 16, 2007
  • #19
I'm not taking offense to anything, or any eyebrow raising at my Hack.Nobody called me a liar, yet. It does seem stupid, and pointless to make a block and do that. I didn't believe what I was hearing either. But I saw the skirts with my own eyes. And they are visibly shorter. He called Ford to make sure he didn't get a mis-cast block. Nope.
Although on ford claimed .125, I wonder if they would recomend that bore in a street car....you can do it in a Dart.
 

mustang6tee8

Member
Jul 19, 2005
375
0
17
College Station, TX
Nov 18, 2007
#20
  • Nov 18, 2007
  • #20
TOM B said:
If the new boss block has shorter skirts than the older blocks Then WHY buy one.
If this is true than why would ord even bother to make the new boss block socalled better and stronger than the old block,, this dont make sense to me.
Click to expand...

because ford says "if they will buy it, we will build it." (seriously). ford and shelby are going on a "special edition" S197 mustang craze. they know that people will pay premium prices for limited number cars.

sorry!!! off topic....
 
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