Greetings,
People have been over this stuff over and over, and I've been through the archives here and a couple of other places (including a great SBC forum on clubhotrod.com). I come from a world where you tune your car with a laptop, and 250 crank hp out of 112 turbo'd ci (1.8L) is no big deal, so I'm an American-iron newbie - please bear with me (or hey, just click the 'x').
My '59 3200 has a 283 in it. I use the truck for daily driving (city driving mostly), and light hauling. I'm not interested in racing it, and probably won't do much towing. Basically I want a good street driver - lots of low- and mid-range torque, decent fuel economy, pump gas (87 octane if possible), decent throttle response, and reliability.
Right now the 283 is pretty much stock, except some parts on it seem to be off an early 60s passenger car. The motor has a Rochester 2G carb, a 265/283 passenger car intake manifold, 283/327 heads (3755549 casting number), rams horn exhaust manifolds, a stock type exhaust, and stock ignition. This truck has an SM420 4-speed and 3.90:1 gears. This truck was restored about 20 years ago, and I think that's the last time the motor was opened up. It has the stock crankshaft in it, so I assume it's the stock pistons too. I haven't had the heads off to check.
I'm interested in keeping up with traffic a little better. In general, I like the 283 - forged crank, short stroke, vintage feel, what's not to like? I want to keep the rams head manifolds, because they look cool; based on my reading, it looks like they don't flow all that well, but I'm keeping them anyway. I also dig the early-type offset-bolt "Chevrolet" script valve covers, but I could give those up if someone convinced me I needed new heads.
The consensus seems to be that a smallish 4-bbl carb works great on the 283. I have an opportunity to buy an unused vacuum-secondary 600cfm Holley 4160 cheap. With that and a decent intake manifold from a swap meet or new, I'd be in business.
Here's the question I really haven't found the answer to: Is it worth it to do this kind of carb/intake swap without also swapping heads? I figure the heads can't be that bad if they were used on '60s 283 Corvettes.
I also have a number of other newbie-like questions, but these are easier to get a read on based on what's out there now, so I sweat these less. Is 600 cfm a little on the big side for an otherwise fairly restrictive intake system? Are the valve seats on my heads going to die anyway thanks to unleaded gas, meaning I should get newer ones, maybe the power pack heads? (I'm too lazy to buy lead additive.) Will aluminum heads with a suitable compression bump kill my cast pistons? Any good intake manifold recommendations for this carb on this motor?
Yeah, I know, basic stuff. Part of me suggests I should leave it well enough alone, get all the gaskets replaced (including, unfortunately, the rear main seal, the timing cover, heck even the pinion seal on the rear end), and call it a day. But I can't really leave well enough alone!
Thanks for any ideas.
-matt
