Is building a stroked 318 better than a stroked 340/360?

Newbomb Turk said

Yeah, bore/stroke/rod ratios DO matter, regardless of what the nonsense on the internet says.

If you just look at rod/stroke ratio and how it affects cam timing. Saying it doesn’t matter is just wrong.

It’s why there is so many under achieving strokers are out there. They added more stroke than they can feed, killed the rod ratio and had to handicap the cam to try and save it.

Look at a Pro Stock engine. You’ll see the rod ratio is right around 1.7:1. Listening to some out there, that’s very high.

It matters. Giving up bore size is also dumb. The same pressure across a bigger bore makes more power.

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A lot depends on your intended use and expectations with budget in mind. A stroker should use longer conrods to keep close to the original rod to stroke ratio. The cheap way for a Chevy 383 is to use the 400 rods and syroker crank. Rod to stroke ratio is not advantageous unless you are building a low RPM pump or generator engine and you are looking for torque. Years ago one of the magazines did a multi issue test, starting with a 350 and then installed a stroker crank with 5.565" rods, being careful to maintain the CR the same. Then they put 5.7 rods in with pistons to match. Cam was the same. The short rod 383 made a bit more power and torque but not what you would expect. The long rod 383 picked up a bit of torque and power. Now the larger displacement needs a bit more cam to really shine. One thing noticed was the long rod engine was quieter.
With the short rods the piston moves away from TDC quickly and should develop good vacuum in the cylinders. Larger intake valves and higher lift should let that vacuum make its way to the carb. LSA is affected slightly, like 0.25°.