Gonna make this redundant to my blog entry, but fireballs are cool enough that I don't think anyone will mind. Tom, Matt and I spent a bit of time at night during the Rolex getting some on-track shots, my goal was to capture some RX-8 fireball/glowing brake rotor shots in the braking zone past the kink. Here are the 10 best shots, shooting with a Canon Rebel T2i and a 24-105mm f/4 lens.
hot rotors make me hot! 
Nice! 
Hey, did Pasterjak sponsor Dempey's car?
The only question I have is- why is the fuel even on when the throttle is closed?
Cool pictures, sure. But computers allow some cool things to be done....
(at least the 69 isn't as rich...)
Eric
So aside from the gee whiz stuff - does this serve a purpose on a rotary?
I mean tuning wise -> dumping in a bunch fuel when the rpm is high & load is low (bottom right of the VE table) - I know it has a cooling effect, but I always stayed away from it when tuning piston engines as it also washes the bores down with fuel. Nice light blue light off on shifts, yes - fireball no....
Also, its possible to get about a 4' ball of fire on the dyno with enough tuning.
Kendall
The announcers said something about the rotaries using fuel for cooling, off throttle.. I don't know if that makes sense.
It is inherent with a rotary as there are no valves to close, so the fuel continues into the engine even after you lift, my RX3 bridgeport used to flame on downshifts every time. It is expected.
Now when we put a 13B bridge into a friends MkII Escort it was another deal, first time on track he engulfed a 968 in a 30 foot flame for a moment. We subsequently discovered his overflow outlet was directly over the exhaust....oooops
Nice photos.
When you close the throttle abruptly, some very rich mixture will go through the exhaust and explode when it gets into the o2. My guess, anyway.
Oooo, please allow me to contribute as well 
...
imirk wrote: The announcers said something about the rotaries using fuel for cooling, off throttle.. I don't know if that makes sense.
Technically, no, that does not make sense. While running rich is cooler than running stoich (and going richer = cooler exhaust), no fuel is a LOT cooler than that.
So, if the goal was really to cool things off.....
aussiesmg wrote: It is inherent with a rotary as there are no valves to close, so the fuel continues into the engine even after you lift, my RX3 bridgeport used to flame on downshifts every time. It is expected.
There are valves to close- they are at the tip of the injectors. It's probably been 3 decades since they had carbs at Daytona for the 24 hrs.
If you had no control over the fuel, yes, I'm sure you would have issues- but with modern and still primitive fuel injection- turning the fuel off on decel's should be easy.
To reply to DDD- a good calibrator can tune out the "very rich mixture" on tip out. The easiest being just turn the fuel off. They are deceling long enough in the corner that there could possibly be a little excess fuel, but it would be gone within 2-3 events.
That's a pretty tough shot to get IMHO. Dark, fast moving, and you are trying to capture glow/flame while freezing the action and keeping everything in focus. Good job.
I feel the take-home message is that I suck at panning shots at night, I need a lot more practice. I had way more terrible blurry messes than decent shots, although the lens certainly helped. Still, I look at the stuff our pros get (admittedly with f/2.8 lenses and super-top-level cameras with full-frame sensors) and figure I'll always be a writer with a camera, not a pro photographer.
Kabel, what were your settings on that nighttime shot of the Dempsey car? That's very, very crisp, and doesn't look like the ISO was too high, either.
pinchvalve wrote: That's a pretty tough shot to get IMHO. Dark, fast moving, and you are trying to capture glow/flame while freezing the action and keeping everything in focus. Good job.
To me, extra props for the blue flame. Those seem to be really hard shots to capture.
So you may need to start a Grassroots Photogaphy page.... 
Really, really cool. On a neat scale, that is. 
Speedhunters had a series of articles where they talked about racecar photography, seemed good for those with a working knowledge of the subject.
note: never read speedhunters comments if you still have any faith in humanity.
no fuel is a LOT cooler than that.
Only if the fuel is ignited in the engine. If it isnt then it's just like water injection.
Vigo wrote:no fuel is a LOT cooler than that.Only if the fuel is ignited in the engine. If it isnt then it's just like water injection.
Not really- and it will start to burn somewhere, and anywhere down from there is hotter than no fuel.
Once the engine is hot enough, fuel at +120F isn't going to cool too many things. Moreso that I would bet that all of the fuel is being injected as a vapor, not liquid- which happens about 1-2 min after the engine is first started.
there might be another reason. But I don't see cooling as one of them.
(and I still say that the photos are very cool. even if I don't agree with why they do it)
These are 3-rotor engines, and that means they're not Renesis-style sideport, but the peripheral-style port. I've never seen a peripheral-port rotary that didn't make big fireballs on lift when things are good and hot.
Scott Lear wrote: ...Still, I look at the stuff our pros get (admittedly with f/2.8 lenses and super-top-level cameras with full-frame sensors)...
You know that some photo shops will rent you pro lenses for the weekend? A buddy rented a f/2.8 for indoor Christmas party pictures this year and it was amazing. Cost him $30 for two days.
The fireballs off the front straight were pretty cool to watch. It seeme like their yellow flag engine map also allowed for a lot of flames.
kabel wrote:
This one is particularly nice (they're all nice 'cause fire is nice) but this one is super nice!
It's amazing to me how, in way less than one wheel revolution, the disc is already noticably cooler.
kabel wrote: Oooo, please allow me to contribute as well
I bet Dermpsey racing would like some of these on Facebook if your willing to share
Rotarys just flame more even in street cars possibly due to much higher exhaust temperatures. Full throttle rotary exhaust 1700F- 2000F while a piston engines 1100F - 1400F.
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