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

would putting allitle hard block in my block be bad?

  • Thread starter Thread starter IndyBlk5.0
  • Start date Start date Jul 30, 2004

IndyBlk5.0

New Member
Nov 24, 2003
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New Whiteland, IN
Jul 30, 2004
#1
  • Jul 30, 2004
  • #1
I was thinking less than a 1/4 hard block. I don't want to run into cooling issues. Does this stuff actually make your block that much stronger? If so, how much? Is it worth it?
 

shttygtstang

New Member
Jun 2, 2004
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Jul 30, 2004
#2
  • Jul 30, 2004
  • #2
wuts hard block
 

TIMMY2734

Founding Member
May 17, 2002
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36
Queens, NY
Jul 30, 2004
#3
  • Jul 30, 2004
  • #3
If you are redoing the rotating assembly, it really wouldnt hurt much. But if you want to do it in what you currently have, i wouldnt waste my time..
 

TT91

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May 23, 2003
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Paramus, NJ
Jul 30, 2004
#4
  • Jul 30, 2004
  • #4
it works, there is alot of info if you search around the web about filling our blocks properly. Good luck
 

5.0 HOtrain

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Jul 31, 2004
#5
  • Jul 31, 2004
  • #5
Mine is filled up to the water pump. With the same 3 core stock replacement, stock clutch fan, and edelbrock 5.0 waterpump mine runs around 165 with a 160 t-stat, no cooling issues at all.
mike.
 

IndyBlk5.0

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Nov 24, 2003
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Aug 1, 2004
#6
  • Aug 1, 2004
  • #6
How much would this help with the block holding more power?
 

90mustangGT

I felt sorry for girls because
Founding Member
Jan 15, 2002
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89
Dallas, GA
Aug 1, 2004
#7
  • Aug 1, 2004
  • #7
I've heard of that stuff, how do you "put it in the block", I am guessing by what 5.0HOtrain said throught the water passages.
 

IndyBlk5.0

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Nov 24, 2003
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#8
  • Aug 1, 2004
  • #8
Wow, send me a pm on what you can take for that s trim and aftercooler sureshot... I might be interested =)
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
Aug 2, 2004
#9
  • Aug 2, 2004
  • #9
Filling the block does help keep the cylinder round and strengthen around the bores. Unless you go up the water pump holes it is a waste as far as adding strength, it also needs to be done before the block is machined, properly with a torque plate or head bolted in place to keep the block from twisting.

The block will still break straight up the middle since it is very weak in that area. Hardblok does more for a Chevy small block then a Ford based on the internal passages.
 

IndyBlk5.0

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Nov 24, 2003
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Aug 3, 2004
#10
  • Aug 3, 2004
  • #10
Well what can i do to strengthen the block to handle about 500rwhp ?
Thats going to be on a conservative tune by the way.
 

5.0 HOtrain

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Aug 3, 2004
#11
  • Aug 3, 2004
  • #11
With a filled block in the 69-74 age range you will be fine around 500rwhp. Just add a girdle for piece of mind. As with the hardblock, make sure the main line is torqued and honed with the girdle on there.
mike.
 

IndyBlk5.0

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Nov 24, 2003
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New Whiteland, IN
Aug 3, 2004
#12
  • Aug 3, 2004
  • #12
Mike, the 351 is down in Tenn getting built piece by piece when I find good deals on misc parts.
This is about my 306 stock blocked blower motor.
 
T

tjm73

Founding Member
Aug 3, 2000
2,418
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48
Rush, NY
Aug 4, 2004
#13
  • Aug 4, 2004
  • #13
IndyBlk5.0 said:
Well what can i do to strengthen the block to handle about 500rwhp ?
Thats going to be on a conservative tune by the way.
Click to expand...


This is probably not what you want to hear, but with what you have for parts and what your goal is, I would not waste anytime with the factory block. Buy a FRPP wet sump racing block. It'll have the strength you are going to need to keep that motor in one piece.

You are going to spend a coupel hundred bucks on a girdle. Take that $300 and add about $1000 to it and go buy the M-6010-R302 block. You'll never break it. Think it's too expensive? Add up building your stock block and then add up building another for when you break it. It won't seem that expensive when you add up that cost.
 

TT91

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May 23, 2003
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Paramus, NJ
Aug 4, 2004
#14
  • Aug 4, 2004
  • #14
tjm73 said:
You are going to spend a coupel hundred bucks on a girdle. Take that $300 and add about $1000 to it and go buy the M-6010-R302 block. You'll never break it. Think it's too expensive? Add up building your stock block and then add up building another for when you break it. It won't seem that expensive when you add up that cost.
Click to expand...

How about 1600 for an R302 block, and then the price of machining it, another 500-600$...The lowest deal I've found so far is 2200 for a machined r-302 block to your door. Stock block have been known to hold 550 rwhp without a problem.....www.turbomustangs.com
 
M

madbrad

Member
Mar 6, 2003
72
0
6
Albuquerque NM
Aug 4, 2004
#15
  • Aug 4, 2004
  • #15
I did a lot of research on hard blok and came really close to putting in my 351. If you use the brand "Hard Blok" they told me you can do it after the machine work had been done. But as people have already said it dosent really strengthen the block. Also to put it in you have to have the block bare and depending where you wan to fill it you might need to remove the freeze plugs. If i were you i would pass on it and use a girdle and make sure you get some good machine work done.
 
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