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When an aluminum block grows #2663884
06/08/19 11:19 PM
06/08/19 11:19 PM
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Washington
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hemienvy Offline OP
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hemienvy  Offline OP
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Washington
Say it grows .012" when warm. Does that push the cylinder liners up in their bores .012" as well,
so that the head gasket seal is unaffected ?

Part II: If the aluminum grows at a different rate then the iron liners, which it does,
how can an all-metal MLS gasket possibly work ( in this application) ?

Last edited by hemienvy; 06/08/19 11:46 PM. Reason: added material.
Re: When an aluminum block grows [Re: hemienvy] #2663896
06/09/19 12:18 AM
06/09/19 12:18 AM
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Great Neck,LI,new york
hemi-itis Offline
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Great Neck,LI,new york
The alumiminum heads with aluminum stands can grow 10 thou!


HEMI-ITIS has no cure.
My condition is fully BLOWN!!
Re: When an aluminum block grows [Re: hemi-itis] #2663897
06/09/19 12:55 AM
06/09/19 12:55 AM
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Huntsville, AL
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Airwoofer Offline
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Cool question. If the aluminum was expanding more than the steel liner due to the different alpha values, you would assume the interface between the sleeve and the block would also be moving and there would be wear and witness marks.

My guess is the tight fit has them fighting it out internally in the molecules and no slippage / change at the head surface. I need new sleeves in my KB block so maybe I can find out when they get swapped.

Re: When an aluminum block grows [Re: Airwoofer] #2663923
06/09/19 05:00 AM
06/09/19 05:00 AM
Joined: Mar 2005
Posts: 1,581
N/E, Michigan
RATTRAP Offline
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The correct terminology is (CTE) Coefficient Thermal Expansion of a given material.

The Steel will grow just over 1/2 the rate of the Aluminum depending on the composition of the material involved.
One has to remember the material is growing in all directions not just one.

Last edited by RATTRAP; 06/09/19 05:02 AM.
Re: When an aluminum block grows [Re: RATTRAP] #2663924
06/09/19 05:08 AM
06/09/19 05:08 AM
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The Netherlands
BigBlockMopar Offline
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Something to consider... the steel of the liners is more in direct contact with heat than the rest of the block...
Eventhough they are surrounded with coolant, they still have to cope with combustion heat and additional friction heat from the piston rings.

Re: When an aluminum block grows [Re: BigBlockMopar] #2663925
06/09/19 05:18 AM
06/09/19 05:18 AM
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N/E, Michigan
RATTRAP Offline
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The liners would Probably grow a little faster than the aluminum block as they are seeing a higher temp from the direct heat source.

Re: When an aluminum block grows [Re: RATTRAP] #2664026
06/09/19 01:28 PM
06/09/19 01:28 PM
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A shed in England
Tig Offline
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A shed in England
Lash on our 580 opens by 12 thou when warm (ali block ali head). With 1.6 rocker arms thats only 7 1/2 thou in total (roughly). It was only 6 thou with an iron block, ali head.


'74 Challenger..9.46 @ 145.9 1/4, 6.001 @ 118 1/8 so far. 4023lb !!! # N/A, Marsh performance 655ci, Indy Maxx, T/R, Indy 600-13 X's, Street legal, pump gas, full interior, Cal-Tracs, mufflers, 3:73's and real 10.5 radials.
9.51 @ 142.4 1/4, 6.003 @ 114 1/8 with our old mule KB, 572-13, 580 wedge.
RHD '68 Barracuda Fastback 323ci street/strip. Best ET 13.88 @ 99.03
Re: When an aluminum block grows [Re: hemienvy] #2664039
06/09/19 01:59 PM
06/09/19 01:59 PM
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Bend,OR USA
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Cab_Burge Offline
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I have been told that aluminum grows eight times more than steel when heated shruggy
That being said the first aluminum block (KB Street Hemi block with dry sleeves) I assembled had the sleeves installed so the top of them was right at .005 above the block deck, that motor leaked water around the sleeve tops from a water coolant passage under the head gasket until I took the block back to KB and they lowered the sleeves to .003 above and I used a different set of head gaskets designed for THAT block shruggy work
Some of the information out here on race stuff is accurate on the same type of aluminum alloys, not all aluminum alloys grow the same at the same temps shruggy


Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)
Re: When an aluminum block grows [Re: Cab_Burge] #2664214
06/10/19 12:02 AM
06/10/19 12:02 AM
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back in Georgia
dthemi Offline
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All my sleeves are between. 002, and .003 above the deck too. My stuff grows from zero lash to around .025 to .03 if it gets stupid hot. I set up at zero lash cold most times.

As for sealing, i use copper coat on everything. Cometics are amazing, and have worked on almost everything without a single leak. I'm growing ever more fond of the sce ics titan copper. They have a stainless ring sandwiched in the copper around the bores like if the block were o ringed, and printed sealing material around the water. Im sure it's not quite as good as traditional wire o rings, but close enough for me. I've been abusing a set for a while now. Melting pistons, detonation, reusing, and they keep going. I like the heat transfer of copper, but have never liked the re torque, water leaks and being stuck with wire in the sleeves. Im building a pretty mean blown motor ( mean for a cast water block and head) so I'll see if they'll take some real pressure.

Re: When an aluminum block grows [Re: Cab_Burge] #2664241
06/10/19 04:44 AM
06/10/19 04:44 AM
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Posts: 1,581
N/E, Michigan
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Originally Posted by Cab_Burge
I have been told that aluminum grows eight times more than steel when heated shruggy


Per degree F x10^-6

Aluminum = 13
Steel = 7.2







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