iPhone Dynolicious Software More Accurate than G-Tech? - Garage419

we use standard suction cup camera mounts, and just attached the iphone to it with rubber bands....

One question: what kind of windshield mount did you use while running the test? I've bought the app (for iPod touch) and used it. It's great fun, but I feel the results might be more accurate with my iPod mounted to the car as opposed to me holding it down with one hand on the passenger seat. I did a quick search online but most windshield/suction cup mounts seem to have bendable/flimsy arms, and nothing looks as sturdy as what I see in the video by a long shot. Any brands/links/prices you could recommend? Much appreciated.

I thought it was funny that you got a call while you were making one of the runs. Doh! I told a friend that story, and he said you can put it in "Airplane Mode" to block incoming calls. Probably a good idea if you're gonna mount the phone while Autocrossing or racing. Don't need the wife calling while making that hairpin turn.

Apparently, ET is simply a measure of performance and doesn't start ticking until you cross the staging beams. So I stand corrected. Sorry Matt. I'm actually glad to head the results as I'm a fan of the dynolicious.

Matt - i noticed something in your recent Garage 419 test. A little detail that you failed to note - reaction time. This really effs up a key point you were making about the 1/4 miles times. Overlooking reaction time causes a discrepancy between the ACTUAL time it takes when you begin moving and ultimately cross the finish line vs. how long it takes from the time the light turns green to then crossing the finish line. See where I'm going with this? When you showed the drag time slip, the R/T on was .926, that means the car left the line .426 seconds after the green (if you don't understand that, read up on R/Ts). The clock (that ultimately timed you at 15.614) starts ticking at the green. Ruh roh...problems. You threw the gtech pro on the ground and stomped on it because it was almost a half second off the slip time...however you were too quick to do that. The gtech read 15.16. When you add the .426 seconds sitting at the line (while the clock is ticking)...the time is TADA...pretty fuggin accurate (15.58). The iPhone reported 15.64 --- which you played it as "OMG!!! .01 off of the slip time" --- however, when you add .426, the iPhone is now the one a 1/2 second off and the gtech pro becomes the winner of 1/4 mile drag time. Needless to say, the $13 app is cool, and a great measure of relative performance (when comparing to another dynolicious result). And from what you say about the functionality of the gtech and the $150 price tag, I'm in even more support of the dynolicious. But, you and Garage 419 went way out of their way to prove the point --- the wrong way. Nuff said.

Dynolicious is a great app and for the price can’t be beat! Seems pretty accurate and is cool that it’s on the phone so you would already have it with you from car to car for a quick run. Thanks for this episode (and others) and turning me on to something new..btw loving the paint job on the mini!

Great video. I have an iPhone and Dynolicious. It's amazing how accurate it is. But if you want accurate HP numbers it's critical that you get a very accurate weight on your vehicle, including the weight of the driver. On the drivetrain loss, I guess about 20% is pretty close on most vehicles, right? Anyway, I love my iPhone. Matt, you gotta get one. There are so many other cool apps out there for the iPhone.

Jovo, maybe I'm missing something here. When an object is at rest it is experiencing 1 vertical G. Why is it so hard to calibrate since you can just turn it on it's side and get a baseline, accurate, 1g reference from nature?

Jovo, thanks for the remarks, they were very informative. It seems like your design is very compreshensive and I can see that you take a lot of pride in what you've done. The one thing I think that this video highlights is something so important and crucial to your future design and business existence and that is this: Convenience and marketing dominate over quality and precision every time. Luckily for you, the people on here prefer precision and quality over convenience and marketing, or else we would all drive Chevy Malibus. I see that your product is awesome and well designed and now it's time to "keep up with the joneses" so to speak and find a way to make your meter more compact, easier to use, and all the other things that the instant gratification society we live in wants. your product is something that 15 years ago would never have even been thought of and it's amazing to see how far we have come. Now make that thing easier to use and integrate it into a portable nav system and we'll have a winner. This isn't to say that your work has been in vain, as you have definitely worked hard, but any product that stays fresh has it's tweeks. Thanks again for the concise info you provided.

Hello, my name is Jovo Majstorovic and I have designed all four generations of G-TECH products. I have to say that this video is very upsetting, throwing a product to the ground, that’s not very nice. The entire video seems very biased. However, in this comment, I will try to be as unbiased as I can. First of all I need to say that I also love my I-phone. It truly is a marvel of modern industrial design and manufacturing, that precision, quality, finish, user interface, all great stuff. In fact I am a big fan of Apple and many of my college friends (Art Center College of Design in Pasadena), work there. While you can pay as little as $200 bucks for an I phone, it should be mentioned that this pricing is heavily subsidized by a two year contract and that the actual price of the I-phone is around $500-700. Here are a few facts that you may find interesting relative to this video: Accelerometers in the I-phone are used to determine if the product is moved, rotated etc. They are not calibrated to the precision level that G-TECH accelerometers are. Video neglects to mention that the user has to calibrate the accelerometers. To do this right, is not easy and is temperature dependent. If you are lucky, you did the calibration at the same temperature as your measurements otherwise you will be off. G-TECH accelerometers are robotically calibrated and temperature-compensated, I-Phone accelerometers are not, they don’t need to be, so it’s all up to the user and to do a calibration better then a robot is simply impossible, believe me I know. I have several patents in the field, just go to www.uspto.gov and do a search by my name. No mention of the roll-out in the video! As all of you more experienced drag-racers know, it all happens right there in the first 60ft and the roll-out is the most important part of it. If you deep-stage on the track and you use a 12” roll-out, the resulting discrepancy can be even bigger than half a second! No mention of the pitch correction! Pitch is the rotation of the car due to suspension compliance and G-forces. To have the “correct” measurement without correction for the pitch of the car as it rolls down the track is simply blind luck! 1.5Gs on a Mini?! Video indicates that a Mini pulled 1.5Gs. This is simply impossible and is due to what we call kinetic-dump. This is the force resulting from the engine running freely for a period and than dumping that energy on to the drivetrain. Obviously not proper dampening algorithms are used in the Dynolicious software. I have spent last 15 years on the drag strips and racetracks testing measuring equipment for vehicles and I am here to tell you that this is not as easy as it seems. There is a great deal of variables to contend with. If you neglect the variables and your measurements seem “correct” you were simply lucky! That seems to be the case with the horsepower measurement in the video. Here is why... It is physically impossible to have the same horsepower numbers on the dyno and in real life. On the dyno the car is strapped and standing still and it doesn’t have to contend with air-resistance. Without the exact aerodynamic drag coefficient and the frontal area of the vehicle it’s impossible to determine the exact horsepower loss due to air-resistance. So to have the same numbers on the dyno and the I-phone is simply blind, unsubstantiated luck! The I-Phone is great, this Dynolicious app. is also kind of neat, but this measurement method is simply no match for a factory calibrated G-TECH. With proper calibration service for of each and every customer’s I-Phone, improved software and proper customer support we may have a contender. Thanks for listening.

so matt, i think the real question is, how did it feel getting stomped by that mk2 gti. just kidding bud i thought the production on this episode was great and the whole story interesting. i think i need an iPhone now. the best 13 bux a couch racer can spend

I have an iphone with the Dyno software but it sucks, doesn't work. I did a run with my 05 BMW 525 and it said that it was a 18 sec car, dont think its that slow

no it doesnt. look at the PASS software for Gtech pro RR, and show me where the iphone does that. its a very valuable tool for a road racer

Ok...back the truck up. As far as a price point goes you are right. The iphone software is better. But as functionality goes you are WRONG! even the host said it himself, he has one but has never used it. Thats the problem! Ok so the iphone does one thing and its a 1/10th more accurate, but the Gtech Pro RR does wayyyy more...I mean for you host who cant drive anything but a straight line its great, but for some of us who take the twisties it has PASS software which logs your car and can prove as a useful tool for those of us who actually race. And as far ass it falling off your windshield well then clean it first with some alcohol and then stick it on...Ive had mine for a year now and it has never fallen off. That was a very biased episode by two guys who seem that they received a kick back from Apple. You need to show ALL the functions of a Gtech before you make a decision. Thank You

I thought it works with the IPhone and IPod touch ?

Guys that was an awesome episode. Not only is the dynolicious thing interesting and amazing...the episode was really well produced. Multiple locations, too (dyno and track). So well done. But hey, are you sure you can put that software on an iPod? I dont think so, but an iTouch (the thing that looks like an iPhone but doesnt have the phone functionality). COrrect me if Im wrong, but I think the accelerometer on those devices is what alows it to go from portrait mode to landscape when you turn the device on its side. The iTouch and iPhone (with the fancy screens) do that, but not the standard iPods. Please tell me if im wrong. In anycase, its impressive that apple used accelerometer that is good enough to tacke an application it was never intended for. And its more impressive that some dude recognized its potential and build an awesome app for it....and for racing, no less!

think u so much to show me why how that works b/c i was think how in the f--k does that work with out bein it hok up to the car and that cool as hell know i m goin to buy a ipod thoch and i dontlike atat they suck

about the smaller displacement caddy motors i think its a great idea to choose if ya want a smaller engine but is it for just the cts or is it all models tho and with the i phone jazz thats pretty wicked

Great episode!!! It's funny that thbe G-Box is so wrong and that the I-Phone is better... In Germany we have a data recording system for homeuse which is called Driftbox and this system should work properly!!!