# Iron Block Vs. Aluminum block **URL:** \ **Category:** SON240sx Automotive\ **Created:** [December 12, 2004, 6:03pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454 "2004-12-12T18:03:48Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![DETS14](https://avatars.discourse-cdn.com/v4/letter/d/ee59a6/32.png) [@DETS14](https://forums.speedlife.net/u/DETS14)\ **Post date:** [December 12, 2004, 6:03pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/1 "2004-12-12T18:03:48Z")
Which do you guys think is best. List pros and cons of both with examples. They both have their positives and negatives. ---
**Author:** ![\_RSTuning.ca](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/_rstuning.ca/32/6098_2.png) [@\_RSTuning.ca](https://forums.speedlife.net/u/_RSTuning.ca)\ **Post date:** [December 12, 2004, 6:29pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/2 "2004-12-12T18:29:30Z")
iron is best becuase its a billion times stronger the minus is that it weighs more the aluminum isnt as strong but it lighter. ---
**Author:** ![s13Junkyard](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/s13junkyard/32/5502_2.png) [@s13Junkyard](https://forums.speedlife.net/u/s13Junkyard)\ **Post date:** [December 12, 2004, 6:31pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/3 "2004-12-12T18:31:13Z")
Iron all the way ---
**Author:** ![japaneseimports.ca](https://avatars.discourse-cdn.com/v4/letter/j/e9bcb4/32.png) [@japaneseimports.ca](https://forums.speedlife.net/u/japaneseimports.ca)\ **Post date:** [December 12, 2004, 7:13pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/4 "2004-12-12T19:13:27Z")
Hey isn’t the CA18DET an Iron block? ---
**Author:** ![RD\_Man](https://avatars.discourse-cdn.com/v4/letter/r/a88e4f/32.png) [@RD\_Man](https://forums.speedlife.net/u/RD_Man)\ **Post date:** [December 12, 2004, 7:15pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/5 "2004-12-12T19:15:05Z")
> [@japaneseimports.ca](#): > > Hey isn’t the CA18DET an Iron block? ya thats one of the reasons it was scrapped, it cost to much to make it ---
**Author:** ![system](https://canada1.discourse-cdn.com/flex034/uploads/speedlife/original/2X/b/b7170c8eddc0b95ece6b88172b2f416a08489a45.png) [@system](https://forums.speedlife.net/u/system)\ **Post date:** [December 12, 2004, 7:18pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/6 "2004-12-12T19:18:16Z")
> [@japaneseimports.ca](#): > > Hey isn’t the CA18DET an Iron block? :twisted: :twisted: :twisted: :twisted: ---
**Author:** ![SHIFT\_KA24DET](https://avatars.discourse-cdn.com/v4/letter/s/b9bd4f/32.png) [@SHIFT\_KA24DET](https://forums.speedlife.net/u/SHIFT_KA24DET)\ **Post date:** [December 12, 2004, 7:31pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/7 "2004-12-12T19:31:24Z")
ALUMINIUM = BIG BOOST IRON = BIGGER BOOST ---
**Author:** ![system](https://canada1.discourse-cdn.com/flex034/uploads/speedlife/original/2X/b/b7170c8eddc0b95ece6b88172b2f416a08489a45.png) [@system](https://forums.speedlife.net/u/system)\ **Post date:** [December 12, 2004, 7:42pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/8 "2004-12-12T19:42:54Z")
need better internals for bigger boost :S - metal headgasket… ---
**Author:** ![\_RSTuning.ca](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/_rstuning.ca/32/6098_2.png) [@\_RSTuning.ca](https://forums.speedlife.net/u/_RSTuning.ca)\ **Post date:** [December 13, 2004, 5:37pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/9 "2004-12-13T17:37:00Z")
you shouldnt need a metal gasket if detonation is not present. ---
**Author:** ![nocwage](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/nocwage/32/5489_2.png) [@nocwage](https://forums.speedlife.net/u/nocwage)\ **Post date:** [December 14, 2004, 5:57am UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/10 "2004-12-14T05:57:17Z")
When you’re pushing boost you should plan for some accidental detonation… I’ve heard the CA actually weighs less than the SR because it has a timing belt instead of a chain and it does’t require rocker arms since it’s got 16 lobes for 16 valves. The SR also is a lot thicker to make up for the weaker aluminum. NOTE: I haven’t weighed it myself so take that with a grain of salt. If it doesn’t weigh less it probably weighs the same. ---
**Author:** ![boMex](https://avatars.discourse-cdn.com/v4/letter/b/7bcc69/32.png) [@boMex](https://forums.speedlife.net/u/boMex)\ **Post date:** [December 14, 2004, 6:54am UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/11 "2004-12-14T06:54:49Z")
This discussion is useless. A well built aluminum block will be strong and make good hp and a well built iron block will be strong and make good hp. ---
**Author:** ![GT1](https://avatars.discourse-cdn.com/v4/letter/g/b5e925/32.png) [@GT1](https://forums.speedlife.net/u/GT1)\ **Post date:** [December 14, 2004, 7:11am UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/12 "2004-12-14T07:11:18Z")
exactly… it depends waht your intentions are for the motor. too many variables to decide a winner in my opinion. and personally i would always go with a metal head gasket and upgraded head studs when upping the boost to much higher level however like i said… too many things to consider. you would need a flow chart to even think of discussing this with any proper arguement. nehoo continue to debate if you want GT ---
**Author:** ![SHIFT\_KA24DET](https://avatars.discourse-cdn.com/v4/letter/s/b9bd4f/32.png) [@SHIFT\_KA24DET](https://forums.speedlife.net/u/SHIFT_KA24DET)\ **Post date:** [December 15, 2004, 8:27am UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/13 "2004-12-15T08:27:29Z")
> [@GT\_GREG](#): > > you would need a flow chart to even think of discussing this with any proper arguement. > GT We’re talking about Blocks not Heads 😉 ---
**Author:** ![GT1](https://avatars.discourse-cdn.com/v4/letter/g/b5e925/32.png) [@GT1](https://forums.speedlife.net/u/GT1)\ **Post date:** [December 15, 2004, 12:09pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/14 "2004-12-15T12:09:37Z")
and talking about a flow chart not a chart that shows teh flow. different things yo GT ---
**Author:** ![AnDrEw](https://avatars.discourse-cdn.com/v4/letter/a/f19dbf/32.png) [@AnDrEw](https://forums.speedlife.net/u/AnDrEw)\ **Post date:** [December 15, 2004, 1:57pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/15 "2004-12-15T13:57:11Z")
> [@boMex](#): > > This discussion is useless. A well built aluminum block will be strong and make good hp and a well built iron block will be strong and make good hp. :stupid: ---
**Author:** ![spilner](https://avatars.discourse-cdn.com/v4/letter/s/f17d59/32.png) [@spilner](https://forums.speedlife.net/u/spilner)\ **Post date:** [December 15, 2004, 5:09pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/16 "2004-12-15T17:09:35Z")
theres a reason the SR is so popular… dont second guess the pro’s. ARUMINURMN BROCKK!!! DORIIIFFFTTTTOOOOUUUUUU!!! ---
**Author:** ![Hector](https://avatars.discourse-cdn.com/v4/letter/h/43a26b/32.png) [@Hector](https://forums.speedlife.net/u/Hector)\ **Post date:** [December 18, 2004, 11:09pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/17 "2004-12-18T23:09:22Z")
iron block is stronger, but i would choose aluminium for one reason, we have aluminium heads!!! aluminium and iron have different expansion rates, using dissimilar metals is never a good idea, with iron blocks and aluminium heads u tend to get head warpage more than u would iif both were aluminium, also aluminium dissapates heat quicker than iron, exactly what u want in a high performance motor, less chance of heat soak into the engine bay after engine shut off as well, cuz as we all know heat soak creates a whole whack of problems! Engines with dissimilar metals for head and block tend to have more headgasket problems as well!! just my two cents ---
**Author:** ![SHIFT\_KA24DET](https://avatars.discourse-cdn.com/v4/letter/s/b9bd4f/32.png) [@SHIFT\_KA24DET](https://forums.speedlife.net/u/SHIFT_KA24DET)\ **Post date:** [December 19, 2004, 4:08pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/18 "2004-12-19T16:08:35Z")
> [@Hector](#): > > iron block is stronger, but i would choose aluminium for one reason, we have aluminium heads!!! > > aluminium and iron have different expansion rates, using dissimilar metals is never a good idea, with iron blocks and aluminium heads u tend to get head warpage more than u would iif both were aluminium, > > also aluminium dissapates heat quicker than iron, exactly what u want in a high performance motor, less chance of heat soak into the engine bay after engine shut off as well, cuz as we all know heat soak creates a whole whack of problems! > > Engines with dissimilar metals for head and block tend to have more headgasket problems as well!! > > just my two cents And you got this information from where? ---
**Author:** ![Ed1](https://avatars.discourse-cdn.com/v4/letter/e/958977/32.png) [@Ed1](https://forums.speedlife.net/u/Ed1)\ **Post date:** [December 19, 2004, 7:07pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/19 "2004-12-19T19:07:27Z")
it does kinda make sense, w/ the different expanding rate for each metal, and they do expand at different temperature, (according to my physics text book 😃 ) idealy no one would want to have something that expands and different temperatures and have it break b/c of that ---
**Author:** ![SHIFT\_KA24DET](https://avatars.discourse-cdn.com/v4/letter/s/b9bd4f/32.png) [@SHIFT\_KA24DET](https://forums.speedlife.net/u/SHIFT_KA24DET)\ **Post date:** [December 19, 2004, 7:13pm UTC](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454/20 "2004-12-19T19:13:31Z")
> [@Ed](#): > > it does kinda make sense, w/ the different expanding rate for each metal, > and they do expand at different temperature, (according to my physics text book 😃 ) > > idealy no one would want to have something that expands and different temperatures and have it break b/c of that Do you know exactly how much the difference is? Not much, IIRC .05mm^3/1000deg… [Next page](https://forums.speedlife.net/t/iron-block-vs-aluminum-block/82454.md?page=2)