Re: 23rd Series 356 Engine Noise

Posted by PackardV8 On 2008/12/14 9:04:04

Follow Owens advice above about the different seat angles.

I don';t know what the 356 valve angles are but i'm guessing AT LEAST one of the Int or Ex. is NOT 45 degrees. This can present a problem for MANY machine shops and i've ran into it even at an old reliable well established shop i used.

The problem is that there is no longer much demand for seat angles that are NOT 45*. So the machine shops have NOT kept the seat stones maintaned. It's a bad case of the old SBC coming back to haunt us again. Based on my occasional visits to machine shops over the last 10-12 years about 80% of customer parts laying around in the shop for service are SBC. SO the 30-something degree seat angle service is not in high demand and the stones and 3/8 mandrels are not maintaned.