Basically as the title says. I hear a lot that data acquistion with predictive lap timing features are a huge benefit, especially for DE students and instructors. Why is that? What can I gain from it and are there difference between predictive laps from each device?

any help is appreciated...as most of the googling leads to marketing material...or is this just hyped up?

 

It let's you know whether or not trying something worked now versus when you cross the start/finish. I know that the higher end stuff does a better job, and I'm not 100% impressed with the Trackmaster's predictive timer out of the box.

 

It's basically that it gives you instant feedback. Even with reviewing video and data immediately after a session, it's easy to forget EXACTLY what the car felt like during every corner of every lap in a session. A regular in-car lap timer serves the same purpose, but it only tells you how changes affected overall lap time. If you lose .2 sec in turn 1 but make the time back up in turn 4, a regular timer doesn't teach you anything. With a predictive timer, you immediately see that what you did in turn 4 was worth .2 sec and can apply that to your next lap.

 

I have Trackmaster and have not started using it's predictive lap timer feature.
I assume I need to:
1. Set it to the "Predictive View".
2. Put my phone where I can see it.
3. Just watch for Red vs. Green.

Any other suggestions?

 

Dat mouth-breather.

 

Set a bunch of split markers. I was just using a single split marker at the Start/Finish and it wouldn't really tell me anything useful since it would be +/- 2 seconds depending on how fast the car was currently going. I think if you give it more resolution with individual sectors, it will actually produce useful data.

 

I love my aim solo. Predictive timing Lets me know if I'm wasting my time going 100% (may crash) also saves my tires and brakes. which is $$$. its worth every penny.

 

Its a must have for new tracks. I took an underpowered scca prod car to pocono for a scca national race. Its a roval so only half of it (or less) was road course. 1st session I was 12 seconds off the pace. By the end of practice & qual I was 0.3 seconds off the lap record. There was a bus stop chicane in the back of the oval, I was able to slice 4-7 seconds off just by trail braking the entry a few different ways to see what worked.

It still worked on "home" tracks but not as extreme, I took it to grattan later that summer and "only" picked up 0.4 seconds. However it was handy for trying different entry / apex points during overtaking lines.

I like the idea of the instant feedback i got every corner - I could see my best lap number drop with every corner & it was serious challenge to "not f it up". I learned the hard way that overcooking one corner killed all the gains I had on the previous 4 corners.

I was using an Aim MXL pro FWIW.

 

because exit speed don't mean squat:
you can take a line that's 100 yards longer, yet exit faster. but your lap time would be worse than if you take the shortest line.

because mid corner speed don't mean squat:
to maintain the highest mid corner speed, you take the widest arc. but that's don't mean it is fastest. just mean you have highest speed. you can often take a shorter line, and have a lower lap time.

driving fast is not the same as lower lap time.

 

As others said, instant feedback. I went to Blackhawk Farms for the first time this weekend and it was great to get feedback on different lines and the impact they were having on my time. Certain things that felt slower turned out to be the quickest way around that particular corner.

 

Put a carrot in front of the horse and he pulls the carriage faster. Predictive Lap Timing is a huge carrot for most drivers.

One of my lap records is the direct product of having PLT in my Stack dash. I saw that I was "up" on my best lap a fair amount going down the back straight at Portland, pressed hard through the final corners and carried more speed onto the front straight. Crossed start/finish, jumped on the brakes for the chicane and tore the center out of a rear caliper. But I got the record! Not a Miata, BTW.

Even if you have fluffed a lap early, PLT is still beneficial. You know the lap is trash, so try a new line through one of the subsequent corners.

 

I'm looking at getting the AiM Solo over the winter in addition to a GoPro (I'd go for the SmartyCam buy $1000 vs $300-400 is a bit much).

Is there a good software package for overlaying the AiM data over the GoPro footage?

 

Saves on wear and tear. Run 10 laps to satisfy the poisson statistics, then park your car and see who has the smallest time peak. lol

 

RaceRender LLC Products

 

I second that, good software. If you have a couple cameras you can do split screen or picture in picture also.

 

This as succinct as I have read on the subject.

Watching the Japanese GP last night I saw the Marussia drivers taking later apexes than the leaders as they came through. The misconceptions exist at every level of motorsport.

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Regarding the OP, the single biggest benefit of predictive for most drivers that, used correctly, it allows a diligent driver to find time on track faster than any other method save a coach in the right seat with a headset. The reason why is that you can compare segments even on a bad lap. All you need is a clear run at any given turn or segment for the predictive to compare against your previous best. So even in traffic on a typical race warmup or HPDE session, you can be tweaking your line.

This won't apply to too many readers here but I found it an invaluable tool to stay on target lap times in an enduro when the lap time was well under what the car was capable of. That's surprisingly hard to do without PLT. Once I got a rhythm, I'd expect to see a certain positive number at a few spots on track. If I was under or over a tenth I would just shift earlier or later (already short shifting) to keep the PLT on a specific target. That's one of the ways to run exactly say, 2.5s under the cars qualifying pace for 3 hours and deviate less that .4s either way.

 

If you have a Iphone or Android smartphone try the Harry's Lap Timer app.

 

I was at an Autox discussing Harry's Lap Timer app with a guy driving a NA, and he seemed to like it. Easy to setup a new track I think. Just press start, walk the autox course, press stop. You are good to go.

Something about it can overlay onto a GoPro really easy or something similar also.

I haven't personally used it, but it seemed like a good deal for ~$5.

 

The built-in phone gps is way too slow to get good info out of it at autocross. It updates once a second. You would need a bluetooth 5hz or 10hz gps for better results.

 

RaceChrono. It is free. It isn't predictive but it has been useful.