How do the newer Vortex KZs (VTZ, RTZ, RSZ) compare to a TM R2 or even R1 in terms of power, build quality, maintenance, ease of tuning, etc.? The IAME screamer also seems to be rising in popularity a bit, how are these compared to the gold standard TM? Do the Vortex KZs have the same gear box as the rok shifter? Out of the box are the Vortex KZs prepped? For the same price as an out of the box Vortex I could get a prepped TM. Same with the IAME, 6k retail, is it prepped? What you guys even mess with getting a IAME?
I know nothing except Danny Formal just said he was the only Vortex in the entire SKUSA field in Pro Shifter. (He Won) soā¦ maybe if done correctly the Vortex can be quite good.
Yea, he also won in 2019 on the Leading Edge FK with a Vortex KZ. Seems like they have good pace in them, Iām not sure why people donāt run them more often. I wouldnāt think that, it being an OTK product would stop people that arenāt on OTK chassis to run it so there might be other things? I believe Kremers also ran one at the FIA world championship a couple months ago. Iāve tried to look online but canāt really find much first hand info about running them.
Pretty sure you can buy a retrofit kit to convert your ROK to KZ spec. If youāve got a good motor and know how to work on them I would start there before buying a brand new engine package.
The way I see itā¦it all depends on what you can and want to do with your time, knowledge, connections (and money)
Example: if you are racing without the support of a team and have no tuner, then you are better off with a TM.
If you have access to a tuner, then it will probably be either TM or Iame, depending on what the tuner is using.
If you have connections or a tuner that is developing a āboutiqueā engine, then you can go Vortex. As an end customer, Iame and Vortex will be far more expensive to run than a TM, but they are all very capable platforms
I went with a Rok due to the longer service intervals and availability of parts. Iām on a KR chassis, so Iām ambivalent to Vortex being an OTK product.
I have lots of time, good knowledge, and zero connections really. Iām in Socal and run a GFC with FW, Iāve been having Swedetech work on my Rok, mainly honing the cylinder and had them rebuilt the gearbox and go through the crank and such. Though they rebuild it I wouldnāt really say I have a relationship with them to where theyād help me with tuning besides some simple jetting, especially since its a rok and theres not much to do. Though some of āfactoryā guys rok engines sound very different to a normal oneā¦ I really enjoy the tuning and working on my kart/engine just as much as driving, so I think Iāll take over a lot of the maintenance besides honing and other things that require equipment I donāt have. After reading through your post about maintaining a KZ Iāve found that it seems cheaper to run than a Rok. Is an IAME harder to tune? Why would you advise only getting an IAME if I have a tuner? I was looking into Vortex and base retail price theyāre already more expensive than a TM, which is a proven engine, especially with a factory prep. PSL has some R2s for sale since supernats just ended, would you advise against getting an engine that was used for one race like supernats? Do they usually run them hard and on the edge, so much so that itād be a bad purchase second hand?
Iāve thought about this, but Iām kind of leaning towards just buying a new engine package. 1 because TM seems cheaper to run besides a couple things and 2 i just really want a TM again. Also I think that if shifter has a chance of getting back to anywhere close to wear it once was it will be through commitment to the KZ.
Out of the box, a factory-tuned (black edition) TM is a very solid engine you can unbox and race. The R2 is the 4th iteration of (pretty much) the same engine platform. So tuning, jetting etc is common knowledge across tuners and racers around the world. New piston is $67 and new conrod kit $225 just as a reference point.
The Screamer 4 is a slight variation of the 3, it had very small market share but recently made a giant leap forward in terms of performance and adoption in Europe but also in US. However, itās still a much less common platform, so tuner knowledge makes a difference in this case, knowing what works vs what doesnāt. Again, if you like to tinker and test and try there is nothing magic about it, just less reference points. Piston is $100 and conrod kit is $305 so quite a bit of a jump vs TM. BUT if you get good used engines and support from Swedetech, maybe it makes sense especially as they would be familiar with jetting and setups that the rest of the GFC team uses, since you are on that bandwagon.
As far as buying either engine brand from Supernats, I would have no qualmsā¦they are for sure good engines to begin with, used by pros that know what they are doing. Iād rather have that than an engine of unknown origin, potentially used by somebody who tried to engine brake by downshifting at 17K rpm. Just donāt overpay for it.
Formalās Vortex, Wickās IAME Screamer 4, and Dennerās TM KZ-R2 represent the end point of long and expensive development programs and selective assembly and dyno tresting of the resulting parts. They are probably the 3 strongest reed valve 125cc engines ever built. The sale of many similar sngines and chassis depend on their success. Their builders prefer to keep them in the hands of drivers and teams capable of winning the SuperNationals.
Outside of that - a ācolor codedā TM KZ-R2 will have a pretty decent level of preparation, and TM has the production volume and experience to build high quality parts. For $5500 you can get yourself an engine that will rarely be found wanting and will probably make it to its annual rebuild without trouble.
How do small shops like Swedetech end up with these top tier engines? Is it from taking a run of the mill engine and just tuning it and modding it to make it the best or do they buy a ton of them and keep the ones that make the most power out of the box or what?
TM seems to be the better choice for me. When looking into the costs I was surprised to see how affordable they actually are, for some reason people like to push the narrative that theyāre just insanely expensive to maintain and need to be fully rebuilt after a few hours. When in actuality the intervals arenāt much different to my Rok shifter AND the parts are much cheaper. I donāt have a good enough relationship with a tuner to learn about the Screamer 4 whereas with the TM I can find tons of info online.
Parametric study: theyāll take cylinders and modify them step by step on port height, transfer angle, transfer radius, etc, between the as-manufactured starting point and the rules limit, running it between each change on a flow bench, then take the most promising configurations, plate the cylinders, build them into engines, and run them on a dyno with several pipes until they find a local optimum configuration.
Then theyāll build several engines the same way, test them, and with any luck get a couple of very strong ones.
Also he has to be the largest volume shifter engine tuner in the US.
Swedetech also works on plenty of TM stuff. The TM that Fore won with in Masters was a Swedetech KZ R2. If youāre already working with Swedetech via Formula Works then I would just call Reine and talk through your options with him.
As Charles pointed out, Formalās engine is essentially hand picked from the OTK factory. Iāve seen others use the Vortex here in the US, and while they have reported strong dyno numbers, the on-track performance hasnāt been quite as strong as it was with the TM (same team, same drivers).
Iāve been extremely happy with the quality of the TM (R1), and would absolutely recommend the engine for anyone looking to step up to KZ.
Iāve always wondered, are engine tuners getting cylinders that are unplated, or do they strip the plating before doing extensive port work, and the subsequently replate them?
A parameter study is a systematic way to vary several model parameters and have the system automatically run one or several analyses for each combination of parameters.
I am no wiser for this alas
Parametric Analysis - Basic Tutorial
Step 1 - Create a base model. ā¦
Step 2 - Run a standard simulation. ā¦
Step 3 - Define optimisation problem on Optimisation Analysis Settings dialog. ā¦
Step 4 - Open Optimisation Calculation Options dialog. ā¦
The one part that is not mentioned above is that a massive factor is the on track, pre-session tune that is been done by tuner and driver. I bet if we were to test the top 10 engines the day after the race, weād find out they are pretty leveled. Jetting, pipe selection, stiffeners and all those small little tricks, when done at the right time, all combined make a measurable difference at that level. Thatās why Franco, Swedetech and all the top dogs are there in person, there is no rocket engine that alone saves the day because it was built with voodoo tech. I know top tuners that do not believe in plating, flow benching or dyno. I just talked to one that won national titles multiple categories, and didnāt do any of those 3 things but is firmly convinced the secret is somewhere else. KZ yes he run different pipesā¦2 in total so nothing that cannot be replicated (if you know how). And thatās the whole point, the difference is made by people who know what they are doing and tweak things at the right time in the right way. And remember itās tuner but also the driver who knows what to relay back and how. And even at that level they make bets that some time work, some time donāt so you canāt really infer by what happens in a final.
Go check what Simone posted about Pex at the FIA World finals in the other post, it would have been impossible if the secret was inside the engine and guarded by the big teams. You can go at it from multiple angles and every one has its own recipe and beliefs, but it all comes down on how you dial in and chase conditions for the given session.
I can go on and so apologies for the long rant but thatās the beauty of KZ, infinite opportunities that anyone can have access to, if enough time is invested I think itās important for people to understand that spending a fortune on super special engines or this brand or that brand will not automatically translate in super special results. Itās more complicated, you need to know how to manage what you have on hand. So working with a tuner that is open to discuss options and try things with you, or doing and learning by yourself is much more valuable than any extra money you spend on uniquely crafted engines.
That is a totally different mindset and work approach compared to a spec class, so teams that built their success around managing a spec platform had to adapt (most did it and did it very well, few didnāt), but I can assure you itās not a matter of having access to special equipment.
Now Iāll go back to my basement and stop posting for a week, I promise
I think itās important for people to understand that spending a fortune on super special engines or this brand or that brand will not automatically translate in super special results. Itās more complicated, you need to know how to manage what you have on hand. So working with a tuner that is open to discuss options and try things with you, or doing and learning by yourself is much more valuable than any extra money you spend on uniquely crafted engines.