I start from the axiom that you don't want to open the engine, because this means costs for work and spares, expecially because when you lift off the head there's no possibility to know whether one or more liners have followed even slightly the head gasket, unseating the bottom o-ring. Because the o-rings are old and rigid, they are hardly able to reseat themselves correctly when disturbed. This means that, if you want to be sure your water will not flow into your oil, you need to dismantle completely the engine and change the o-rings. I didn't do that, and after 3000 km the fourth rod started knocking...
So, if you want to save money, you are forced to live with the original ducts and CR. Luckily, even if both are not the the state-of-the-art for today's standards, they surely were at their time.
The other point is that the 1300 has the highest power/displacement ratio of all the alfa street engine till the twin spark (montreal excluded). This means you cannot expect great improvement without altering the torque band, translating the peak to higher revs.
With the long ratio axle of the 1600, you don't have great margins in loosing low-end torque.
So you have to think "torque oriented" instead of "power oriented".
That's why you shouldn't do what I did on my car. My engine is peaking somewere near 7000, but you have to make a great use of gearbox in the twisty roads, as torque start to be interesting around 4000.
So, in my opinion you have to:
1) free the airflow of the intake using full radius trumpets and possibly a gta-style airbox to breath calm air and reduce intake noise;
2) free gasflow in the exhaust with a tricky header. If you don't find something made specificaly for a road going 1300, then save your money and keep the original one.
3) use a mild set of camshafts. I used C&B, but they rob some low-end torque, and require a higher CR than standard. I never tried, but some people with 2L are happy changing the intake cam alone, reporting a very flat torque. This may be right for your purpose. Change followers when changing cams.
4) Lighting the flywheel is very simple on a lathe, the hardest part being the removal of the gearbox. You can rebalance it to get the best job, but it's not mandatory;
5) even the best engine can't run well if ignition timing and fuel ratio are incorrect. The carbs will need rejecting (probably only main jet and air corrector): a lambda sond and an inboard reader are a definite help in reducing trial-and-error effort. Ignition advance curve is a very different matter. Theorically, you would need a lot of dyno work, a blocked distributor and an exhaust gasses pyrometer to found the right curve. IMO, if your engine is close to standard you can live well with the original curve, maybe retarded a couple of degrees. If you have a pyrometer, you can set the distributor reading 740°C at maximum advance.
Electronic ignition is so better than points that it's out of discussion keeping the original point/condenser unit. You can fit a kit for your distributor or fit a whole new unit. There is the 123
123ignition electronic ignition systems for classic cars that have a lot of curves implemented, and this is a great help in searching for the right one.
Change wires, plugs and coil regardlessy of their apparent conditions.
6) electric radiator fan gives you some very quiet horsepower
7) You can try with using a single-row cam chain, considering that cams are mild.
BTW, if you like using the gearbox, you can use wilder camshafts and increasing chokes diameter to 29 or 30 mm. In this case, my advice is to use the shorter fifth gears of the 1300 junior (0.86 ratio).
that's what I honestly think.
Alberto
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