LT1-LT4 Modifications - Is this forged?




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lt1_2buku
04-22-2012, 02:31 PM
I know one of you gurus can tell me just by these pics if its a forged crank or not?
http://i1270.photobucket.com/albums/jj602/Tx_Ts/IMG_0544.jpg


http://i1270.photobucket.com/albums/jj602/Tx_Ts/IMG_0548.jpg

http://i1270.photobucket.com/albums/jj602/Tx_Ts/IMG_0434.jpg


ElkySS
04-22-2012, 02:43 PM
it looks to be. does it say 4140 any where?

lt1_2buku
04-22-2012, 02:56 PM
No. I do not see 4140 on it anywhere. I do see 13022 on one of the counter weights though. I did a search and found a kit with a XXX13022XXXX part number that was a cast crank. Im hoping this is not the crank from that assy.


lt1_2buku
04-22-2012, 03:40 PM
Some more. The one on the left was the old eagle cast that came out of my motor. The one on the right is the new "forged" crank. Any thoughts?




http://i1270.photobucket.com/albums/jj602/Tx_Ts/IMG_0551.jpg

http://i1270.photobucket.com/albums/jj602/Tx_Ts/IMG_0550.jpg

http://i1270.photobucket.com/albums/jj602/Tx_Ts/IMG_0553-1.jpg

RamAir95TA
04-22-2012, 04:48 PM
Does the new one have a casting line anywhere?

93 LT1 Vette
04-22-2012, 04:53 PM
Does the new one have a casting line anywhere?

Yeah look at the casting line. Cast cranks will have a small casting line about 1/16 of an inch. Forged should be somewhere around 3/8. At least thats how the 2 piece cranks were way back when.

lt1_2buku
04-22-2012, 04:58 PM
unfortunately I can not find any kind of line anywhere. I did stand them both up and tap them lightly with a hammer they both make the same High pitched ring. I really cant tell any difference between the two. Im wondering if way back when I ordered my first cast crank I received a forged one or if this time I ordered a forged crank I got a cast one.

popo8
04-22-2012, 05:09 PM
Call Eagle and tell them what it says on it.

My original motor had a :forged" crank in it.. but after I broke it in half, and pulled it... I called EAGLE.. and they said my original motor builder screwed me....

97Z28SS
04-22-2012, 05:21 PM
Easy way to tell is to take a wrench and hit both cranks, all forged steel cranks will "ring" while all cast cranks when hit will make a "thud".

lt1_2buku
04-22-2012, 05:33 PM
Thats the thing thats confusing me they both ring. They sound no Different. They are both either cast or both forged. I will take them both to a machine shop tomorrow and see if they can tell.

defaultexistence
04-22-2012, 06:18 PM
Just call eagle! Avoid the whole guessing game.

lt1_2buku
04-22-2012, 06:24 PM
Its Sunday! I will be calling them tomorrow. Just wanted to see if anyone knew how to tell from a cast Today. Is that ok?

F0x Slaughter
04-22-2012, 06:58 PM
Is there a casting line on it?

Forged items are beaten into shape which makes them much stronger.
Cast is poured which means they are weak.

Here is a good read.

http://www.precisionenginetech.com/tech-explained/2009/06/02/forged-crankshaft-tech-part-1/

lt1_2buku
04-22-2012, 07:48 PM
Thanks Fox Slaughter that was a good read. For some reason either crank has any kind of casting line that I can see.

lt1_2buku
04-27-2012, 08:36 AM
Its Cast. Thanks for the help guys. Anyone have a forged crank thats not listed in the Classifieds for sale?

Boosted Firehawk
04-27-2012, 09:13 AM
Damn that sucks about being cast.