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Aluminum vs. Cast Iron block (331/347 Turbo)

  • Thread starter Thread starter velocity
  • Start date Start date Jun 27, 2004
V

velocity

New Member
Nov 12, 2003
48
0
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Colorado
Jun 27, 2004
#1
  • Jun 27, 2004
  • #1
Sorry if this topic has already been covered.... I did a search and did not see anything.

I was wondering what the pros/cons of an aluminum block are compared to a cast iron one??

I am thinking of getting a new block and having a 331/347 turbo for at least 500HP. Would one block be better for this over another?

Thanks for any input!!
 

yellow5.0cobra

Founding Member
Jul 25, 2002
2,849
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0
In the garage, On the floor.
Jun 27, 2004
#2
  • Jun 27, 2004
  • #2
WHAT aluminum block?

there is NO production ALUMINUM block except for a VERY expensive AFTERMARKET block that is somewhere about $2800, minus machine work.

So please share this information with me(us).

500hp, get a regular 5.0 block, or upgrade to a Sportsman Ford Racing block for a piece of mind.
 

Grn92LX

Fidanza Man!
Founding Member
Jan 14, 2001
6,819
64
129
New York
Jun 27, 2004
#3
  • Jun 27, 2004
  • #3
Dart alum blocks are about $4200. 500rwhp boosted in a stock 302 block??? Time Bomb!! Get an R block or a dart iron block if you want that 500hp to actually last and be reliable..
 

Sleepy McNastee

New Member
Feb 5, 2004
491
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0
Lawrence, KS
Jun 27, 2004
#4
  • Jun 27, 2004
  • #4
Yeah an aluminum block would be better(lighter), but as said above, way more expensive.
 

yellow5.0cobra

Founding Member
Jul 25, 2002
2,849
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0
In the garage, On the floor.
Jun 27, 2004
#5
  • Jun 27, 2004
  • #5
you CAN get away with 500rwhp with a STOCK block, there are guys running 9's.

its just a matter of who tunes your car.
 
Y

yellow1995Cobra

New Member
Dec 23, 2002
2,959
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0
Massachusetts
Jun 27, 2004
#6
  • Jun 27, 2004
  • #6
I dont see why people would want an alum block. Its like the boosted LS1's, they have alum blocks, and because of the heat expansion of alum, they have a very hard time keeping the heads on the block under high boost.
 

5.0_GT_kid

20+ Year Stangneter
Apr 18, 2004
1,155
1
39
Largo, Florida
Jun 27, 2004
#7
  • Jun 27, 2004
  • #7
yellow1995Cobra said:
I dont see why people would want an alum block. Its like the boosted LS1's, they have alum blocks, and because of the heat expansion of alum, they have a very hard time keeping the heads on the block under high boost.
Click to expand...

I thought that was only a problem when using different material in the head and block..like iron block with aluminum heads
 

Sleepy McNastee

New Member
Feb 5, 2004
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0
Lawrence, KS
Jun 27, 2004
#8
  • Jun 27, 2004
  • #8
5.0_GT_kid said:
I thought that was only a problem when using different material in the head and block..like iron block with aluminum heads
Click to expand...

Iron block w/ aluminum heads is what SVT used for the 03-04 Cobras, so there must be a reason for that. I don't know why though...

Maybe it's a good thing that the aluminum and iron expand differently. Maybe that creates a stronger seal than two like metals expanding at the same rate.Just a thought.
 

5.0_GT_kid

20+ Year Stangneter
Apr 18, 2004
1,155
1
39
Largo, Florida
Jun 27, 2004
#9
  • Jun 27, 2004
  • #9
Sleepy McNastee said:
Iron block w/ aluminum heads is what SVT used for the 03-04 Cobras, so there must be a reason for that. I don't know why though...

Maybe it's a good thing that the aluminum and iron expand differently. Maybe that creates a stronger seal than two like metals expanding at the same rate.Just a thought.
Click to expand...

Very true, but at higher performance levels, I figured it would be a problem. I'm not sure though.
 

95GTvert[bv12]

Founding Member
Apr 1, 2001
1,792
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37
Lake Tahoe, NV
Jun 27, 2004
#10
  • Jun 27, 2004
  • #10
well aluminum blocks can be repaired when they split you can weld and fix them. and if you have and aluminum block and heads you should be fine...LS1's have problems becuase of the high compression ratios
 

swingline

New Member
Sep 18, 2003
1,252
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0
TCB - Taking Care of Business
Jun 27, 2004
#11
  • Jun 27, 2004
  • #11
5.0_GT_kid said:
Very true, but at higher performance levels, I figured it would be a problem. I'm not sure though.
Click to expand...

There are 03-04 Cobras making over 1000HP without problems. Not with the block anyways....
 
V

velocity

New Member
Nov 12, 2003
48
0
0
Colorado
Jun 28, 2004
#12
  • Jun 28, 2004
  • #12
Thanks for all the info.... I did not realize that the Dart Aluminum block was $4200. I asked my girl friend what she thought of me getting one of those and she said "What does my new girl friend think of that?" I almost fell off my chair laughing so hard.
 

5.0_GT_kid

20+ Year Stangneter
Apr 18, 2004
1,155
1
39
Largo, Florida
Jun 28, 2004
#13
  • Jun 28, 2004
  • #13
velocity said:
Thanks for all the info.... I did not realize that the Dart Aluminum block was $4200. I asked my girl friend what she thought of me getting one of those and she said "What does my new girl friend think of that?" I almost fell off my chair laughing so hard.
Click to expand...

You should break it off with her and tell her she's too expensive and if you stay with her you won't be able to afford your block
 

mstangfrk95GTS!

New Member
Mar 20, 2004
203
0
0
Jun 28, 2004
#14
  • Jun 28, 2004
  • #14
screw that, get a Level 10 or 20 DSS and call it good, thats all id spend on a block.

if your looking to make over 500 Hp and are serious, you should be able to afford a Sportsman.
otherwise get something you can break without crying LOL
 
Y

yellow1995Cobra

New Member
Dec 23, 2002
2,959
2
0
Massachusetts
Jun 28, 2004
#15
  • Jun 28, 2004
  • #15
95GTvert[bv12] said:
well aluminum blocks can be repaired when they split you can weld and fix them. and if you have and aluminum block and heads you should be fine...LS1's have problems becuase of the high compression ratios
Click to expand...

Most serious boosted ls1's dont have stock heads on them. So the C/R ratio is much lower.
 
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