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cuda620

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Does anyone know what the hp/torque limits on a cast 360 LA crank is? Thanks
 
No personal experience here. But from what I have read here and elsewhere, 500 hp at 6000 rpm. After that you are playing with a grenade with the pin pulled.
 
I have spun a stock 360 cast crank upwards of 7500 rpm for several years with stock rods and heavy trw dome pistons.....the rod broke...the cranks still alive these days
 
I don't know if means a lot, but all the experts say that the stock block will give out long before the cast iron crankshafts will. I have read in one of the infamous (maybe notorious?) Mopar magazines that the later 360 cranks starting around '77 were stronger than the earlier ones because they had been subcontracted to be cast by GM at that time but I have trouble believing it... an early 70's spun out 400 cast crank will break any piece of cast iron this side of an anvil that it's thrown at, including ford and gm cast iron crankshafts... I believe it was strong as one of the earlier forged cranks.
 
I have always used truck cranks in my 360's 7500 rpm 's all day with no problems even going up in the air and coming down with your foot still on the floor with big sticky tires
 
I know ChrYCo shot peened and heat treated and sometimes nitrided the truck and very high performance cranks, I am wanting to say the MP engine manual stated the 360 truck cranks recieved special treatment but I don’t remember exactly what it was.
 
I have an early 360. From what if read it can be bored out to a 340 size with plenty of material left but I won’t incase I abuse it. Thanks
 
72-74 360 water jackets were cored on 70 340 T/A molds, the cylinder walls are nearly siamesed between cylinders in a few examples. One of the better stock casting blocks you can find this side of an R block.
 
cuda620 said:
Does anyone know what the hp/torque limits on a cast 360 LA crank is? Thanks
Click to expand...

As with all things, careful assembly, proper oiling, light reciprocating components.........I would say you are safe to 600 plus hp and 7000plus rpm
 
Glad to hear such positive feedback. I may have to do this instead of the 451 I had planned. Thanks
 
Probably depends on the use. It might not play well with repeated hits of Nitrous or really high Boost
 
For a naturally aspirated build, it’s safe for 500-550hp with main studs before the main webbing in the block becomes a concern. The girdle from hughes or at least millling and strapping the caps is a good idea beyond that but usually there is more at play when to say you need those items than just a horsepower number such as projected rpm, severity of usage, and weight of the vehicle it’s going in. Somewhere along the way to large power, the extra webbing in the blocks that are designed for four bolt mains is necessary. The other add ons can carry you to a point, but become a gamble at best.
 
I was thinking about it cause I have a 67 Cuda318/904. I was thinking bout a bigblock swap but this would be easier.
 
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