Anything to help it exhale to a point is good. You can over do your exhuast though, I'm no expert so I'm not going to rattle off any diameters for you. Maybe a search can guide you there or a more knowledgeable member will jump in here. Same goes for the carb/intake. I'm still learning as well, and I don't want to over carb your motor If your operating in the stock RPM range though, money spent on the intake/carb might be better spent else where. I don't think these motors ever had a problem getting air in until you start messing with cam duration and porting heads.
ive got weiand stealth and a 750 holley with a nitruos express 200hp plate on a stock botom end and havent had any trouble out of it yet it on my 71. before i spooled the rearend it would dangnear do an endless one wheel peel.every thing cost me less than a grand to do.if you actualy cared about blowin the engine(i dont have spares) i wouldnt run over a 150hp shot tho
->It seems that the consensus around the FTE forum is that headers help alot. Finish off the headers with a nice 4" diesel catback(nice mandrel bends are nice too) or custom 3" true duals with some high flow straight trough mufflers.
->Carb spacer maybe? Its cheap too.
->Under drive pulley? I dont know if anyone even makes one, just shooting from the hip here.
->construct some sort of cold air system to reduce the intake air temperatures, and run a 180* thermostat.
What year engine? What vehicle is it in?
Depending on what you have I would upgrade the intake to an aluminum dual plane manifold. Maybe a Weiand Stealth or Edelbock Performer. Headers would be the #2 upgrade. After these two perhaps some nitrous.
Used parts can save you money too, sometimes good stuff shows up in the classified ads in this site.
you can get an underdrive from ebay... they have them avail every once in a while (v-belt-single or dual sheave). a better distributor can help (HEI), plus higher compression (9-10:1) will make it run alot better. of course, headers and intake will always help. then, spend a little bit of time getting it all tuned in, you'll be surprised. nitrous is a good , affordable alternative, but you have to consider your comp. ratio, timing, spark plug temp, and engine temp (you could could modify these to get impressive results w/o the nitro). but funny gas is a blast.
yeah it is fun the only thing i dont like about it is the 30 mile ride and the 50bucks it cost to refill the 20lb bottle.be for i installed a spool in the rearend a 1/4 mile one wheel peal was very possible.now with good tire and spool about a block long