how to tell a motor is forged?
how to tell a motor is forged? i am looking at picking up a t/a with a fully forged motor but the owner says he doesn't have receipts and cannot get ahold of the original builder. Is there a way for me to tell for sure if the motor is forged or not?
To answer your question you need to drop the pan.
A forged crank will have a wide parting line where the forging dies separate. It can be 1/4 to 1/2" wide and shuold have signs of being cleaned with a grinder but will be raised. A cast crank will have a very thin parting line. A real expensive crank will be machined all over and you will know it by the smooth finish it has.
Forged rods if unfinished will have the same the wide parting line about 1/8 to 3/16 wide on old school forgings. If new high tech forgings they may be completely smooth finish from being ground or machined after forging. Late model cracked rods look smooth but are a light weight design versus a froged rod.
Pistons is a real guess but from the bottom if you see sharp parting lines on the ribs going to the skirt they are cast. If smooth thick ribs they could forged or hypereutectic or cast.
A forged crank will have a wide parting line where the forging dies separate. It can be 1/4 to 1/2" wide and shuold have signs of being cleaned with a grinder but will be raised. A cast crank will have a very thin parting line. A real expensive crank will be machined all over and you will know it by the smooth finish it has.
Forged rods if unfinished will have the same the wide parting line about 1/8 to 3/16 wide on old school forgings. If new high tech forgings they may be completely smooth finish from being ground or machined after forging. Late model cracked rods look smooth but are a light weight design versus a froged rod.
Pistons is a real guess but from the bottom if you see sharp parting lines on the ribs going to the skirt they are cast. If smooth thick ribs they could forged or hypereutectic or cast.
No receipts and can't reach the original builder? I would move on.
The oil pan is difficult to remove and I doubt the owner would let you do that kind of investigating anyway.
The oil pan is difficult to remove and I doubt the owner would let you do that kind of investigating anyway.
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From: Michigan (Macomb or Lansing)
Originally Posted by nomorews6
Is there a way for me to tell for sure if the motor is forged or not?
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Originally Posted by pHEnomIC
Take a snailshell with you and run it with some insane boost. If it blows, it isn't forged
stock LS1s can survive repetative 300 shots, id spray like a 400+ just make sure you dont run out of fuel
as for answering your question.. like said above the only real way would be to take the oil pan off..
as for answering your question.. like said above the only real way would be to take the oil pan off..
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From: Vancouver,[KITSILANO].B.C. Canada *WestCoast*
Originally Posted by NxLS1496
or hit it with a 300 shot of teh nawzz and see what happens lol.
..YEAH....Nawzz will do it. .................. 
a 500 shot. 
