I am thinking of throwing a small charger at my 300 and I would like to know if anyone knows where to find aftermarket parts-intake,cam,lifters,heads,anything really, for this build up How good are the stock aluminum heads? Will anything interchange with a 300? if so what? any recomendations for a build-up? Do they take power well?
'67 300 Hey Jess; You'll get a ton of replies to your question. Short answer, everything you need to build up a 300 into a great street motor or 12-second race motor are available. Crower, Crane, Isky, Comp Cams, Reed, Daytona all grind cams for the 300. Cast pistons are also available from a variety of reputable aftermarket sources like Badger, Manley, and Hastings. Venolia is the only piston maker that I know of that lists forged units in their catalog. Sean Etson, who is the most experienced 300 racer, uses prep'd stock rods with 283 Chevy ARP rod bolts. I believe he once told me that he runs his car through the traps at around 6500. SCAT makes really affordable forged Chevy I-beam rods that are easily modified to fit the 300. SCAT says these rods are good for engines up to 450 HP. Two short comings though. No performance intakes, which is no big deal for a 4500-5000 rpm street motor. And no aftermarket headers, which is a real issue no matter what the application. There seem to be two common solutions to the intake situation that most of the smallblock guys agree on. First, port and polish the stock 4V intake. You can do this manually, which takes a boat load of time. You can also send your intake to a company like Extrude Hone in PA for pressurized extrusion honing for around $500. Labor and tools vs. cash, that's the toss up. The other solution is to fabricate a set of 1/2" spacer plates that will allow you to use a performance intake designed for a 1961-63 215 Buick, now being used in Rovers. Offenhauser, Edelbrock, Harcourt, and Wilpower all make performance intakes for the 215/Rover engine. As far as headers go, it appears that unless you can find a set of the Poston tube headers either from one of the V8 Buick members or on eBay, the big bore Rover exhaust manifolds are the closest things to off-the-rack headers. Look for a member named, "Greg" on the smallblock section. He knows everything about using Rover parts on a 300. I have a '64 Skylark with a slightly overbored 300. It has the stock 11:1 compression ratio, a Poston 110A cam, Carter 500 cfm carburetor, Petronix ignition, and a T/A Performance oiling system. I took it out for a long run today and ran the thing up to 4500 on the highway. The cam really kicks in around 1500 and just keeps on pulling, plus it has just enough lope to make it sound nasty at the street lights. That old speedo was bouncin' over 90 mph, which is plenty for street applications (at least in my town). With the appropriate gears and a trans that's better than the stock ST-300, I imagine that 100-110 is just a whisker away. I have a '65 cast iron motor in the garage, which I will be rebuilding this summer. As you will learn from other smallblock members, the 65-67 heads have substantially larger valves and ports than the '64. In fact, you can use larger V6 exhaust valves to improve the breathing even further. The cast iron intake ports are substantially larger, to match the heads of course. The intakes are not quite "rare," but they are getting hard to find. 500 cfm works great on a 300 street motor. 600-650 seems to be common for the really hot motors. Hope this helps. Mark
