Thread: first 350

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I have the "882" heads which have been described as the "best of the worst" and I had the exhaust ports cleaned up at additional cost after a 3-angle valve job and a slight shave to achieve about 9:1 CR; they were cc-ed to 73 cc chambers with a simple milling. With hindsight I probably could have done better at only slightly more cost with a set of Vortec heads. Check the Summit catalog, it seems to me that the Vortec heads are the most bang for the buck, but of course you can easily spend more for even better heads. Check back with Tech1 and see if he will recommend intake port flow range for your application and match to your cam; very large intake ports will actually harm low rpm performance. Tell him your intended use and the specs of your cam and he can dial it in mentally. The 882 heads look good on paper but I have heard they can crack so we will see. If my heads crack I will go to Vortec heads next but the intake manifold is different for the Vortec heads so you need to decide on whether to use Vortec heads before you buy an aftermarket intake mainifold. Before the added $200 for exhaust port polishing I had the block cleaned and bored 0.030" over, the crank cleaned up at 0.010"/0.010" undersize, new rods and cast pistons with a three angle valve job, new oil pump, Crane Street cam (Z28 specs), new lifters and pushrods for $1600 assembled. With the port polishing it came to $1800. You can get a Mr. Goodwrench long block cheaper but if you change the cam you void the warranty, so I wanted to "know" what is in my engine and chose my own parts but had it assembled by a circle-track racer. I later added cheap Speedway roller-tip 1.6 ratio rockers but I may trim that back to 1.5 on the intake but keep the 1.6 on the exhaust which still adds torque but may give better mpg? Dyno runs show that with a "small" cam the torque can be increased with higher lift on the exhaust valves than the intake valves. Still the power ultimately comes from the fuel so maybe more torque/power automatically means lower mpg? Another interesting caution discussed elsewhere on this Forum is the problem that modern oils do not include the ZDP (Zinc Dithio Phosphonate) needed to lubricate flat tappet hydraulic lifters and some cams will rapidly flatten at break in. I wanted a Comp cam but my circle-track builder would not touch them perhaps because they have rapid ramp lift and may not break in well. I was disappointed but settled for a Crane copy of the Z28 stock cam which is also essentially the 300 HP cam used in the SBC327. My builder favored and recommended a Crane cam so I respected his experience. I am going to use an aftermarket ZDP additive to solve this and continue to use additives later but some folks just use oils for Diesel engines. That is a warning that if you use flat tappet lifters you need to use some additive to modern oils OR go to a roller-tappet cam (more expensive). Although I have worked on flatheads, VW flatfours and Pinto OHCfours, this is my first SBC350 and most of what I know so far has come from the very knowledgable folks on this Forum. Be polite and ask questions and you will find that this is a Forum with world class engine experts! Good luck!

Don Shillady
Retired Scientist/teen rodder