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

[velocity]

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]

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]

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]

Yeah an aluminum block would be better(lighter), but as said above, way more expensive.

 

[yellow5.0cobra]

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.

 

[yellow1995Cobra]

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]

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.

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

 

[Sleepy McNastee]

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

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]

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.

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

 

[95GTvert[bv12]]

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]

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

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

 

[velocity]

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]

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.

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!]

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

 

[yellow1995Cobra]

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

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