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A couple of data points.

My RZ came with Spec2 pipes when I bought it in 93 or so and I wouldn't swap them for anything.  They run clean and make around 56 at the back wheel with stock motor and carbs.

I ported an aircooled RD a couple of years ago and it came with a seized motor and beautiful shiny Lomas pipes.  That one made around 52 at the rear wheel with stock 28mm carbs, and the owner loved it.   

Had DG pipes on an RD400G back in Australia that were OK but not inspiring which should come as no surprise to anyone.

Many TZ racers gutted the thermostat leaving only the outer ring, but they also make sure the bike is properly warmed up before a race.

I suspect that there are two different forces at play here.  140F is about right for peak performance and 160 is OK.  But in the colder weather you may find that your jetting is a little rich for the ambient conditions.

I suspect that the improvement in cooling from Athena to Cool Head will be small compared to a cool head change from a stock head.

And Y E S to Swarbrick pipes.  I had a set for an RD400 project and bought some for a TZ we ran and then found two more TZ sets to use on various projects. The only issue is making sure that the stinger is well supported and welded properly.  We had one pair crack off repeatedly from vibration but we think the welding had made the pipe brittle and fracture prone.

We tend to think of a single wave in each cycle but in reality there are many reflected waves per cycle at all revs, but their impact may change at different engine speeds.

As the piston rises from BDC, incoming air flows in through the reeds but as the flow starts inwards, it sends a negative wave backwards which hits that flat filter end and as with all wave energy, when reflected of a closed end it returns with the sign changed from negative to positive, so that positive wave now travels through the gas back to the reeds picking up fuel on the way.

That cycle repeats somewhere around 4 to 6 times per intake event and the magnitude of the pulse (pressure wave) decreases each time it is reflected, so what the carb "sees" is an oscillating pressure wave through the incoming gas flow.  I studied fluid dynamics a decade or two earlier than M in SC and we didn't have complex computer models back then - or even simple computers either if it comes to that.  And I am pretty sure that I lost that knowledge years ago.

Thinking about the issue, one of the pressure pulses outwards will start as the piston starts to fall and push gas back out of the carbs and that pressure wave will get out through the reeds faster than they have a chance to snap shut.

On a TD3 or TZ, or R5 street bike without filters you can easily see a standing wave reaching back almost to the rear fender and some of that mix always coats the back of the motor.  On a reed motor there is less of a mist to see for sure but the problem was identified by greater minds than mine years ago with hard backed filters which allow the reflection.

I don't think it's worse on a reed motor than a piston port.  I suspect that no one was interested in testing on piston port street motors after reeds were introduced.

Just to be clear, those are both analogue systems as far as I can tell and are not programmable.  The "curve" is a function of component choices in the design and can't be modified or programmed.

That 'curve" is basically the same as an older Motoplat or HPI or PVL.  If you want to program more advance at lower revs or more retard at the top end, after peak power, those are not the ignitions you are looking.

you are correct that retarding the ignition after peak revs raises the exhaust temperature because fuel is still burning as it goes down the pipe.  That rise in temperature creates a faster speed of sound, so the end result is an exhaust that acts as if it was getting shorter and therefore continues to be the correct tuned length way past peak power revs.

And karts are the masters of living in that post peak region.

Road race motorcycles need more torque coming off corners more than they need over rev capacity, though that can be handy too.  And more advance at lower revs when the pipe isn't resonating is critical at lower than peak revs and where bikes spend a lot of time.

PVL, Motoplat, FEMSA and Hitachi TIA self generating ignitions don't really have a curve as such. They do have a slight retard due to the time it takes for those lazy electrons to find their way through the system but beyond that latency, they are static.

If you want a timing curve you need to look at a DC CDI system.  HPI sells one and so do Zeel and Ignitech but they need either an alternator or battery (or both) to provide the power.  There is no way to program those analogue systems abut they were designed with components that allowed for a certain (small) amount of timing curve.

Lucas (prince of Darkness) had an ET system which was essentially an alternator and as such timing changes were very limited to a short period before/after maximum flux. The same idea was used in Kokusan systems used on may factory race bikes from RG500 to Honda 6s.  Alternator generated a large enough pulse as magnets pass the cores to dump power into the CDI box. Very clever but not programmable.

So I think that if you need a self generating digital CDI, you may be limited to HPI. 

Total loss is a term usually used to describe a system with battery but no charging, the others used to be called magnetos but self generating is a probably a better term for them. We used battery plus Dyna but no on board charging on AHRMA race bikes and they are total loss.

A modern self generating system has to have a smooth enough constant 12-15v output to allow timing to be implemented but I could be wrong about the details of how they get a clean supply.

TZs used Hitachi CDI or Motoplat of Femsa self generating set at basically 19 degrees, but I suspect that you could get more drivability out of corners and a wider power band after peak with a digital system. 

You could also consider an RC battery running say 14v with a Zeel or Ignitech as long as your races are reasonably short.  They pack a huge amount of power into a small package.

Stock is nice too and Delkevics at that price sounds too good to be true. if you can get then close to that price, they are a steal.

For more or less the same sort of cash, you could have a set of shiny stainless pipes from Mr Lomas.

The guy that bought the Phat Trakka managed to throw it on the ground a couple of times and the last time destroyed the Jemco pipes and did some other damage, and while i was rebuilding it again, he bought a set of JL pipes.  They arrived fast and are beautifully made. They are also the best sounding individual pipes I have heard on a GT other than 3 into 1s which always sounds awesome.

Not stock of course.

And that billet clutch could be built with a set of straight cut primary gears too.

Just sayin'   

...If you want to do water cooled on a RD, use TZ parts, they're cheaper... and probably better quality

4 transfers? What's the point? If you were making new barrels for a RD why not 6 port? and a boost port?
... and why no removable domes (it would make them cheaper to produce... and better)? or at least some sort of description of the head dimensions.
Seems to me these are strong on bling, weak on upgrade

All good questions but 6 port TZ350G aka 3G3 barrels are piston port and only the works OW31 and replicas had reeds plus 6 transfer ports and they still had small RZ350 sized reed valves. 

RD350LC barrels were being ported back the day to make as much (more or less) power as a comparable TZ350 and they or the RZ or any model of TZ is very old school cool. If the objective is mega amounts of power start with a banshee or RZ and add a stroker crank and big bore CPI barrels and you are looking at over 100-150 hp.

For a reliable street RD making more power than stock in the old configuration, a set of plated LC barrels would be a good place to start. And won't make so much power to overwhelm the chassis.

Looks like an ARD magneto.

Don't think that triple was designed to be ridden.  It's a show bike for sure. It will look great in someone's collection of overpriced cars.

That adapter is way more elegant than the three bolt one I used.

Not sure why an RZ needs a fan, but I just noticed that the hybrid has what looks like a brand new TZ water pump.  Mine are all ground down and scored after sliding up the road with a bike on top of them. 

Nice adaptation.  Did you weld up a boss on the side cover for it to sit on?  I had an adapter plate from a kart mounted TZ/RD hybrid that I used on our RD cases, TZ top end and wet clutch drag race motor.