1978 400 crank question.
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Cevidicus
CevidiGrinch
Cast.
If I recall, 400's only came with cast cranks. There may have been some early 72's that had forged cranks, but Im not sure.
Being a 78, it would have a cast crank from the factory.
If I recall, 400's only came with cast cranks. There may have been some early 72's that had forged cranks, but Im not sure.
Being a 78, it would have a cast crank from the factory.
slickchick
pedal cars only
w o w
I had a 77 400 truck engine I tore down that had factory markings on the crank and 77 date coded std bearings. So, never say never. It just depends..
Cevidicus
CevidiGrinch
So you're saying this 77 had a forged crank? Was it from a manual trans truck?
Yup. Factory steel. Not the first one I've seen either. I did a thread on it when I tore it down. It had the spades, clubs, heart and diamond markings on it. Was no doubt a factory piece. Had properly date coded bearings. The block was even stamped indicating it had a factory undersized bearing. It did too. .001" undersized. I have no clue as to whether it was manual or auto. Just that it came out of a 77 truck.
Cevidicus
CevidiGrinch
Cool. Maybe mine has a forged crank too.
I think its safe to say that most would have a cast crank and if a fella gets lucky, he may find one with forged steel crank. Only way to know for sure is to open it up and look.
I think its safe to say that most would have a cast crank and if a fella gets lucky, he may find one with forged steel crank. Only way to know for sure is to open it up and look.
I never heard of this. Could you tell a little more? Did the cranks have a steel type balancer, or the thick cast one?
HawaiiDuster
Well-Known Member
Learn something new everyday :cheers: I was also under the impression that 400's only came with cast cranks. I might have to start looking at them a little more closely now :glasses7:
turbofreek
batcrap crazy racing team
You can see a visual difference of a forged or cast crank easily.the casting line that goes all the way down the crank OS the tell tail. Cast will have a very thin line(width of a to.her nail or so) where the casting is put together. A forged has a wide mark with grind marks on it usually about a 1/4 Inch or better in width. Also a forged crank looks rough on the counter weights edges. The casting looks cut almost perfectly. Not balance can tell you which one it really is. Only the crank itself.
Hope this is helpful to you. Also I've got a 76 and its cast. So to get one even newer is pretty much impossible to find.
Hope this is helpful to you. Also I've got a 76 and its cast. So to get one even newer is pretty much impossible to find.
In the 70's all big block engines that came with manual transmission trucks were supposed to have forged steeel cranks. The only time I have found that to NOT be true was when the owner changed from an automatic transmission to a manual.
It was a steel crank. It had the correct steel crank balancer.
It really surprised me, too. But what IQ52 says makes sense. Somehow, I think his IQ ain't quite that low.
Happened again just this afternoon. Let a guy use an old Chrysler Newport with a 400 in it for a demo derby. Told him the only thing I wanted back was the 400 engine. Came by today and asked if he could just keep the block if he replaced it with another 400. He had bought a 75 3/4 ton 4x4 pickup with 4 spd trans and a 400 engine. Yep, I swapped him and got another 400 with a steel crank.
805moparkid
Slant and AFX Guy
my dads 440 and my 440 72 and 78 model years, both were forged and both had all the cards lol...
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