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Choosing a Camshaft, L31 engine.

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I have 350 chevy, I would love to add some power with a camshaft, checking the casting numbers I found :


10243880 for the block (not roller)

12558062 for the cyl heads


According to some lectures, that block is used for an L31 vortec engine, and the same for the cyl heads.


Behind the engine there is a TH400 trans, bue I don't know the stall of the converter :( . The rear end is 3.55. 


Now the engine is using a Road Demon carb and an Edelbrock intake manifold, with that info somebody could help me to choose a nice camshaft (street/strip)?


We removed the actual camshaft and just found stamped GM20, in the end a 476 and 251005, and in some place there is a 964 or probably a 6964, the first six isn’t clear.


Reading a little more, I found this link, it seems that the engine could be a 350 H.O.



Thank you in advance, 



Edited by jaguargt

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What kind of driving will you be doing? You want something pretty gnar, or just a bit of an upgrade?

Sorry for the delay in my response... would be something that doesn't need a new torque converter or another heavy mod.


I was thinking about the https://www.summitracing.com/int/parts/cca-k12-242-2/overview/ - 

COMP Cams Xtreme Energy Cam and Lifter Kits K12-242-2


But I don't know if it would be too much... 


Thanks in advance, 

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Remember that with the vortec you are limited in how much lift you can run to about .470" without interfering with the stock valve guides!!! 

That cam you have chosen is probably right on the edge of what you can get away with. 


Those are nice motors hate for you to mash yours up!!

EDIT: according to this article you can only run .420" so I would do some research. http://www.superchevy.com/how-to/148-0208-vortec-heads-valve-lift/ 

Edited by northwoodz

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Vortec heads come with weak valve springs .  You can swap in ls6 springs and a comp cams retainer for a cheap upgrade and be good to around .500 lift . Comp also sells a tool to cut the guide down with a hand drill if your up to pulling the heads off. The xe268 cam is about as big as you want with a stock converter , but its a good daily driver cam .Make sure your timing is around 32 degrees total for vortecs, Also if that carb is box stock its probably  way rich at w.o.t and costing you some power      

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