BBC crank identification help
 

Hi, ive got a 396 i believe crank with a casting number of 3804815. I cant find anything to match those numbers, ive found 3804816 and 3904815 but not what mine shows, here is a pic of it. Just trying to see if its cast or forged so i can sell the rotating assembly i have lying around. Thanks in advance!

http://i18.photobucket.com/albums/b1...o/IMAG0494.jpg

http://i18.photobucket.com/albums/b1...o/IMAG0491.jpg

Can't tell because of angle/clarity of pics. Don't have my crank book with me. Looks like cast.

Rule of thumb. If the parting line on the side of the crank throw is only a line, up to 1/16" wide it is a casting. If the line is 1/4" plus and looks like it has grind marks on it. It is forged.

Stand crank on end, on a shop towel. Rap a counter weight with a hammer. If it goes "thunk" it is cast. If it rings clearly, like a bell, it is a forging.

Thanks bob i think its cast also, im at school now so i cant take a better look at it to tell but i think i remember the parting line being very thin so its probably cast. What would would be a good selling price for the whole assembly, 10/10 crank, forged trw pistons on gm rods, its a 427 rotating assembly all fresh but has sat for awhile.

In the bottom pic, you can kind of see on the bottom throw what looks like grind marks like it has been clearanced or something, would this be a mark of the forging process you were talking about if its not cast? Thanks again

Hard to say on price. I can't sell 396-427 stuff. Everybody around here wants 454-500+ stuff even tho they can't afford it.

Prices here, good crank cast $150.00
rods, good bolts recon $200.00
Old TRW forgings around $200.00

Yeah i kind of figured that, well i'll try selling the stuff for the prices you listed and see what happens haha. Thanks again Bob! Anyone who might be able to identify the crank by the number id really appreciate it. Thanks

third counterweight on a 396 is 3/4 on a 427 it is 7/8 hope this helps

I was told it was a 427 rotating assembly so i assumed he just had a 396 crank and rods laying around as well as a 454 block so he made it a 427 + .030 assembly. When you say the different sizes, you are referring to the counterweight thickness correct?

Pics and more info fom BBC Parts Interchange Manual.

yes the thickness of third counterweight. 396 has a lighter rotating assembly if it is a 396 crank and making a 427 using 454 block probably should have everything balanced for longevity. you can't mistake steel crank. it has a wide parting line. just put a 3/4 end wrench on it it will either fit or not

okay, thanks 1932 batman. I will check it out next time im home but i believe it to be a cast 396 crank not sure why nothing matches the casting numbers though... Its all balanced and im trying to sell the whole assembly to get a 489 kit.