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351 cleveland block strength

  • Thread starter Thread starter monsterstang70
  • Start date Start date Aug 6, 2004

monsterstang70

New Member
Jun 24, 2004
145
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0
Amityville, NY
Aug 6, 2004
#1
  • Aug 6, 2004
  • #1
I am wondering how much power can a 1970 351 4 main bolt block can take because I plan on running maybe 10-12 pounds of boost and hoping like 650-700 hp. Considering that I will be doing a bullet proof rotating assembly with forged everything and splayed main caps also. Do you guys think that the stock block can take this and what should I do to the block to make it stronger.
Thanks
Jhery
 

Hack

15 Year Member
Mar 23, 2004
1,945
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69
Minneapolis
Aug 6, 2004
#2
  • Aug 6, 2004
  • #2
http://www.corral.net/forums/showthread.php?t=526237

Check out this thread. The advice given here is that's a lot of horses for a factory block. An aftermarket block might be a better idea.
 

monsterstang70

New Member
Jun 24, 2004
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Amityville, NY
Aug 6, 2004
#3
  • Aug 6, 2004
  • #3
but do they make aftermarkget cleveland blocks?
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
Aug 7, 2004
#4
  • Aug 7, 2004
  • #4
Well back in the 70's and early 80's that kind of power was being made ( and then some ) in Nascar and Pro-Stock with stock blocks. Why not now? What's changed ? If you want a better Cleveland block then the Aussie block is what you want.
 

Hack

15 Year Member
Mar 23, 2004
1,945
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Minneapolis
Aug 7, 2004
#5
  • Aug 7, 2004
  • #5
monsterstang70 said:
but do they make aftermarkget cleveland blocks?
Click to expand...
No. What some people do is use an aftermarket Windsor block, with Cleveland heads or aftermarket Windsor heads. Did you read the thread I linked to? The guy lists a couple manufacturers. I think he's saying that an aftermarket aluminum block is preferred by some, not that it's impossible to do it with a Cleveland. Some people with high horse motors also fill the block's cooling passages with reinforcing material (probably not a good idea for the street ). Your original question was about making the block stronger.. that's what I was trying to answer with my post.

D. Hearne, if you read the thread I linked to you'll see the advice the guy gives is that it's spendy to make that many horses. He says right in his post that he has a factory Cleveland block and he's making a lot of horses. Back in the 70s they didn't have aftermarket blocks as an alternative.

http://www.network54.com/Forum/119419
http://fordforums.com/forumdisplay.php?f=497&page=2&sort=title&order=asc&pp=25&daysprune=-1
http://www.corral.net/forums/index.php?s=

Monsterstang70, there's some links to cleveland forums. Why don't you ask your question there, or do some searching for similar questions? All I'm going to be able to do is link you to threads.
 
D

D.Hearne

New Member
Sep 29, 2000
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south louisiana
Aug 7, 2004
#6
  • Aug 7, 2004
  • #6
I did read the thread, but as for it being expensive to build a Cleveland with that many horses, that's also true for ANY motor.
 

monsterstang70

New Member
Jun 24, 2004
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Amityville, NY
Aug 7, 2004
#7
  • Aug 7, 2004
  • #7
Thanks alot guys
 
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