Do you have pictures of this? I’m trying to understand how this would look. I inderstand the principal , but not the physical set up.
To further feed the topic, i’ll try to pitch in slightly in terms of the development that takes place at international competition level.
I think a duality that is found in both monomake spec engine classes and CIK classes with open regs is the outmost necessity to have a finished product that respects the strictest and best possible assembly quality. Independent of the added performance of tuned parts, the requirement to match them as best as possible does the difference in the end.
For instance, it is clear that there is a little bit of variance amongst the quality and functioning of ignition modules and rotor/stator combos. It only takes out of these three items to not work in perfect symbiosis with the other two for an ignition point to be off by one degree or to not spark exactly when it’s expected to do so. You can then take this consideration downstream, and consider how this discrepancy is potentially affecting the ability for the exhaust pipe you have on to properly scavenge the exhaust gases that are coming out of your cylinder, based on when combustion took place.
All of this to highlight, as an example, that tuners do indeed match THE ignition module to THE stator/rotor to THE exhaust pipe. It doesn’t mean that any other “wouldn’t work” but, when you are chasing international titles, everything matters. (Which is why teams are seldom happy when we force them to exchange ignition modules for CIK-FIA provided ones during our Events, but the guys that are infront most often than not remain there independent of this variable)
For anyone that is not competing for a win at international level, this will not have an end impact on performance. Anyone at national level is capable of winning events without going through this process, with a well tuned engine and very good understanding of carburation principles.
Nevertheless, i think the stability of the regulations (especially in KZ) has helped the world converge in terms of ultimate performance and the nature of the required work to conduct on a “box” engine to make it work really well, which is the beauty of open spec racing.
It would be cynical to think that factories don’t develop novelties every year here and there based on R&D, but it is not revolutionary stuff. If that was the case, and as stated above, private tuners like Galiffa (2022 KZ World Champ) or Viti Racing (2023 KZ2 Euro Champ) would never be able to compete with factory efforts.
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Is this for me ? This is what it looks like
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Interesting. I still think the mass flow rate would change due to speed as air rushes past the trumpets. Would almost make a Venturi effect reducing the amount of air going in (totally an educated guess).
As long as you always tune around that and always run your airbox in that orientation it doesn’t matter. Same if it is forwards.
I would prefer to just run it backwards to mess with people 
@Simone_Perego yes for you.
Interesting, I imagine he is using either some sort of duct/pipe or drilled the air box to accommodate this mounting configuration. Thank you!
Hmmmm it does make you think though.
Of course there is a degree of variance in relation to speed, even with the trumpets turned like this, but it is a lot less susceptible than when they are directly facing forward and having air rammed into them. Fwd configuration would obviously be better and a lot more beneficial if you had an ECU running injection, but we are slave to a fixed needle and a fixed jet essentially
Only doubt i have is it hasn’t been deployed at international level, and i tell myself there must be a reason…
There are four screws that mate the top to the bottom of the airbox. You can just unscrew them, pivot the top part and re-attach that way. No fabrication necessary 
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Ah, much easier than the airbox on my Rok shifter 
I’d agree that parity is much better than in the older days. Really interesting, for example, that Fore was on an R2 in Masters, but an R1 in Pro. There were lots of R1’s being run very competitively at the Supernats.
It’s very difficult to tune for. Superkarts especially try to make use of ram air, but it’s pretty tricky from what I can tell because of the pressure differential between the incoming air and the (atmospheric) pressure in the bowl and therefore pressure being applied to the fuel as it’s “pushed” through the jets.
I’ve seen some solutions that encase the entire carb in the ram air chamber.
Connect the vent lines to the ram air box to equalize pressure.
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The R1 uses a one piece head, the R2 uses a combustion chamber insert. It might be easier to turn the whole head to set the compression to the 11cc limit than to machine the mating surfaces of the insert so that it still seals to the head and the cylinder.
R1 has combustion chamber insert just like the R2, 10c and any other TM kz 
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Yeah I remember all of my K9’s had interchangeable head inserts.
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I doubt there is much of a noticeable difference between a top level R1 and R2. Put Kremers in his R1 from last year and he would have been just as competitive as he was this year.
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Small detour, I happened to stumble on a Tkart article about a company called DMA Racing Gears that makes seamless gearbox for KZ engines. They ran sxs test with a stock vs modded TM R1. Not a subscriber, so I don’t know what results were. Seems like seamless would make more sense to use it with an ignition cut, but it’s an interesting application none the less.
Yes for sure super interesting tech and I think the article was mentioning 2 to 5 tenths gain per lap, depending on track…however it’s an exercise in theory as the CIK-FIA regulation added gearbox modifications to the specific exclusions so homologated engines cannot be modified in that area. I think the homologation rules also prevent OEM manufacturers from making engines with that gearbox as a native feature. Maybe an option for road-racers if they’ll ever make a retrofit kit
even in the KZ class it wouldn’t be allowed?
I don’t think so. I read the rules and they explicitly state that in the KZ section. But maybe somebody with more expertise in rule interpretation can chime in 
Here.
I believe surface treatments are not considered alterations, as you are not modifying the design per fiche, but not entirely sure as that section appears to be a recent add
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