Thread: 350 rebuild kit

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I would strongly urge you to set the quench on the motor at the optimum of 0.035" to 0.040". This is the dimension from the top of the piston crown to the underside of the cylinder head. The other thing I would urge you to do is choose a piston that has a truly flat top to it instead of just a flat ring maybe 1/2" wide around the perimeter of the crown. Here's an example of the type of piston I would use....
http://kb-silvolite.com/performance....tails&P_id=156
Regardless of what others may think of them, I've used hypereutectic pistons in my builds and the builds of friend's motors and have no bad experiences to report. They use a very tight piston to wall clearance to reduce the tendency of the piston to rock in the bore and keep the rings square. You have to be careful about the ring end gap and follow the manufacturer's recommendations closely, they run wider gaps than cast or forged pistons. Don't have the shop deck the block until you get all your parts together. Have them bore and hone the block for your pistons (by the way, don't bore over 0.020" if you don't have to), then pick the block up and take it home to assemble the crank, main bearings and one piston/rod assembly (less rings) into the block. What you want to do is check the deck height with one assembly only on the number 1,2,7 and 8 holes. Using only one piston/rod assembly will minimize variations in rod length/compression height and allow you to get valid measurements of the deck. With these dimensions written down, you'll be able to tell the shop where to cut the decks to square them up with the centerline of the crank. You'll also be able to determine the thickness of gasket you'll want to use and with the deck height to reach your 0.035" to 0.040" quench. In other words, if the deck will clean up and leave the piston down in the bore 0.010", you would want to choose a gasket that compresses at 0.028" to reach the proper quench. If you have to cut the decks so that the crown of the piston is equal with the deck (called zero deck), then you may want to choose a gasket that compresses at 0.039" to reach your quench.

Use 320 wet sandpaper with water to sand the tops of the pistons to remove all sharp edges and corners, do the same to the combustion chambers in the heads.

These procedures will allow you to run all the ignition timing you want in the motor with junk pump gas.

Resist the urge to overcam the motor for a lumpy "rump-rump" sound. You'll hate the throttle response and soggy bottom end.

If you want to nail down the exact static compression ratio of the motor while you have it down, follow my instructions.......
http://streetmachinesoftablerock.com...opic.php?t=124
You'll need this info to make an intelligent cam choice.