289 and 302 have the same bore and deck height. 8.206. 302 had a different stroke. Either block can be a 347. Early 347 stroker motors suffered from the wrist pin intersecting into the oil ring area of the pistons. They would use oil after a bit. A new generation of special pistons has solved that issue. Ensure you get the newer stuff and don't buy off flea bay.
You need a steel crank and upgraded connecting rods to handle a supercharger. You will also need extreme duty head gaskets like the ones from Cometic. Upgrade to a performance harmonic balancer is a must.
If you build a 347 stroker you need to think about the compression ratio. I have a Weiand Supercharger on a 302 with 10 to 1 compression. I am running 12 pounds of boost at 6,000 RPM. It is stupid fast. Another thing to consider is water methanol injection. I got one from Snow Performance. I am running 18 degrees initial advance with 38 degrees total at 3,000 RPM. Mallory E-Series Distributor. I run 92 octane all day with no pinging. Steel crank, Crower sportsman rods. Hydraulic roller cam done at 6,000 RPM
I had a Paxton back in the day, but the Weiand roots style is way superior in throttle response. Instantaneous is the only word to describe it.
On the camshaft you do not want a radical cam with a lot of overlap. The supercharger will just blow the gas through the motor a low RPM during the overlap period when both valves are open at the same time.
You can get a crate motor with a small cam. I would suggest you specify what you want to do from the start to a good engine builder such as DSS Racing. Have the motor purpose built for the power adder of your choice or you will do lots of changing later.
K-Code performance is really nothing more than a solid camshaft. The K heads had the same valves and ports. All they had was a better valve spring, spring pockets and screw in studs. Better rods and select crank. And a bit better exhaust manifold. You could exceed it performance with the same cam, some aluminum heads (huge benefit), and a set of shorty or better yet long tube headers. For that mild an engine you can run the stock rods and pistons.
Picture below is before water methanol injection.
Sub frame connectors and Caltrac Bars
Stan Johnson long tube headers. Look at the ground clearance! These are on Val's Fastback. Got the same on the blower motor.
Call me at (360) 377-5164. Before 8:00 p.m. (old guy). I love to spend other peoples money!!
How about this!!
