Rams horn and hei questions

['72customdeluxe]

Are the outlets on the slanted 2wd ram horns 2" or 2.25". As much as I like the overall torque and mileage with my setup, I just can't seem to get around the manifold outlet size in my head. Right now I have the manifolds going into 2.25" downpipes that have been severely clearance dented. Then stepped up to two 2.5" Flow 40's dumped behind the cab which will be going bye bye. So anything is an upgrade even if I keep the manifolds. I hate the no crossover sound too. My plan is to either replaced the driver manifold only (cracked when I had to plug up the air injection holes) or get some Hooker headers. Either way, the two initial pipes will be 2.25", then into a 3" single Flowmaster y/merge pipe and into an Xr-1 and out before the left rear tire. I'm afraid of loosing torque with headers as that is all my motor really has and I love it. It's also part of why i'm going to be running a short mildly sized pipe single system (other than being cheap ). Another concern: my ignition consists of a super coil, accel performance module, accel wires, msd cap and rotor. After I got the carb rebuilt and jetted, it still seemed doggy off of the bottom for a light truck with 300 or so lb/ft of torque. So I added 4 degrees timing yesterday, bringing it to 16 degrees initial. Yes, the vacuum advance was plugged and it was at about 600rpm. Today i'm playing with it some more and now have 20 degrees initial. I've heard some of these low comp. smog dog motors like timing, but dang.. Maybe the timing marker is off a little. 170psi compression across the board on 87 octane. Not a rattle or sound under any load with 20 degrees in the heat with and without a/c and full throttle. This has the stock hei mech advance. I've heard those curves are pretty lazy, not giving max advance until too late. Could this be why she likes so much timing? The mech weights do move freely. She runs beautifully and smoother than ever now with the timing change. Sounds throatier too. I think i'm going to play with a mech advance kit. Sucker RUNS now!