#41  
Old 04-17-2021, 08:16 AM
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Mass in the right places be it hard or harder means a lot also!
A block that weighs 800 lbs when the motor may only be only making 100 hp will live forever, in fact you would have to break the crank or a rod to do harm to it!

On the other hand as in our case where the block weights in at less then 250 lb yet we can easily yank 600 hp or more out of it is a far far different story!!

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  #42  
Old 04-17-2021, 12:24 PM
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Quote:
Originally Posted by taff2 View Post
What difference does it make how hard or soft the factory blocks are - there's nothing you can really do about it. Both of the '59 389 blocks I've had were very easy to drill/machine - and these were supposed to be better blocks.
It's an indicator of strength in gray iron.. I'm doing strength analysis on the lifter bores.


Kris.

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  #43  
Old 04-17-2021, 01:56 PM
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Ahem,

Crankshafts: Pearlitic Malleable Iron (1st 1956 PMD cast crankswere installed along with SAE 1046 forged steel cranks in 1956 models) Full descript and annealing process in Paper by K.B. Valentine SAE Vol 66, 1958. Bismuth and boron added to improve precipitation of temper carbon. Iron cranks proved better in machining, wear, fatigue, and field study.

Crankshaft history : forged, Arma Steel, PMi, Nodular Iron. Precision Cast is Nodular Iron.

PMD Connecting Rods : Arma Steel, weight 31.7 oz, or Nodular Iron 1963-1979
PMD "production forged rods: SAE 1140
or Early 60s S.D. versions:SAE 4140 (some not heat-treated).

SD-455 Rods: SAE 8640 chrome-moly Ni steel

Piston Pin: Extruded SAE 1016 Steel
Camshaft: PMI "alloy irom"
Pistons: tin-plated Aluminum alloy with steel struts
Top ring: heavy chrome plated
2nd ring: lubrite-coated
Rocker-Arms: cyanide-hardened stamped steel
Pushrods: Cyanide-hardened steel
Main Bearings: Moraine 400

No block materials callout.
I Seems to be missing a REF that calls out the Valve materials, and such. Might update this.

1968 Pontiac Service Manual:
Block & Heads: Alloy Cast Iron
Crank: PMI (and we know they show a "N", and some 428s show "Arma Steel"
Connecting Rods: Arma Steel
Cam: Hardened alloy cast iron
Crank gear: carburized and hardened steel
Cam: aluminum with nylon
Front damper, flywheel: cast iron

Rings Upper and 2nd- Moly filled channel, cast iron
low perf 2nd rings got lubrite coated iron

Piston Pin: extruded SAE 1041 ( 6-cyl Ext SAE 5015)

Valves: Intakes SAE 1041, HO&RA use SAE 8440, EXH 21-2N
Aluminum faced, Chrome plated stems.


Last edited by Half-Inch Stud; 04-17-2021 at 02:45 PM.
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  #44  
Old 04-28-2021, 05:27 AM
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FYI: Block and cap showed identical dent with 10mm ball and equal force applied....

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  #45  
Old 04-28-2021, 06:41 AM
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Those two checking in at the same hardness is what I would expect.

Thanks for sharing!

__________________
Wernher Von Braun warned before his retirement from NASA back in 1972, that the next world war would be against the ETs!
And he was not talking about 1/8 or 1/4 mile ETs!

1) 1940s 100% silver 4 cup tea server set.

Two dry rotted 14 x 10 Micky Thompson slicks.

1) un-mailed in gift coupon from a 1972 box of corn flakes.
Two pairs of brown leather flip flops, never seen more then 2 mph.

Education is what your left with once you forget things!
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