Thread: need advice on my sbc 350

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The suffix number is stamped on the block deck, passenger side, just in front of the end of the cylinder head and very close to the passenger side water pump boss.....sometimes there is an alternator hiding the alpha-numeric stamping.
http://www.chevyasylum.com/tech/V8Stamp2r4t.jpg

10243880 is the casting number for the Vortec 5700 RPO L31 350 motor that was used in pickups and vans. It is much sought-after because it came from the factory with a roller cam and one-piece rear main seal.

10239906 is the casting number for the L31 heads, the heavy duty ones with exhaust seat inserts. The other head that Chevy used on these L31 motors is casting number 12558062, the lighter-duty version without the heavy duty exhaust valve seats. Seats in the 062 heads were induction hardened.

Here's a tutorial on the heads....
http://www.crankshaftcoalition.com/w..._cylinder_head

Chances are pretty good that the flat tappet camshaft will not last. Here is another tutorial telling you why......
http://www.crankshaftcoalition.com/w...ips_and_tricks

It seems a shame to begin a build with the most sought after roller cam block and best production iron heads that Chevy ever cast up and then screw it up with a flat tappet cam and some fosdick 1.6 rockers.

Edelbrock 7116 or equivalent is the intake manifold you need to use with the L31 heads.

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