Thumper
Autocross Champion
If you all recall I ordered a ModShack VTDA a couple weeks ago and just got to install it today. I wanted to do more than just an install and a "butt dyno" rant/rave. I actually said "Stand back, I am going to try science."
Well, I had some issues with VAGCOM so my dream of beautiful graphs and logs was not to be. I could not get VAGCOM to record my 0-60 and 35-70 times while keeping a record of the other data (RPM, Intake temp, MAF pressure, Boost). It was one or the other. I assume this is due to my newness with the software and I am sure I will figure it out (or someone will post here and explain it LOL). So, hopefully, I will be able to complete my dreamed of testing at a later date.
But I do have some info and a review.......and I have pictures.
Let's start with the install. Package came VERY well protected with everything wrapped in bubble wrap and hardware in separate little baggies with labels. Also included were three ModShack decal/stickers and a K&N sticker. The VTDA itself was wrapped about 7 times in bubble wrap. Step by step instructions were also included and I have to be honest, other than the lack of a "flashy" box, there was nothing that said "amateur". This was a professional presentation all the way.
There was a minor install issue and mistake in the instructions. Not sure if this is because I have a '12 and they changed something. The instructions state to use a T20 to remove the stock airduct from the grille. In reality, these are T25s. The T20 fit and seemed right until I got to the end of the first turn and it slipped. The clamps to attach the reducer were different. One was a bolt head and one was a flathead screwdriver, both were adjustable with a 5/16 open end though.
Install took about 20 minutes and was really pretty basic and easy. Intake is very secure mounted on two brackets at the front grille and supported on the rear using one of the OEM mounting locations.
Now, the IMPORTANT stuff. Performance. All test runs were done on the same stretch of road as each test. The 0-60mph runs were done on a back road near my house with smooth pavement. 35-70mph runs were done on the state highway nearby. AC was off, traction control was off. Baseline tests were done at 9AM-10AM, with VTDA installed tests done at 11:30-12:00.
Baseline tests were done at 55F, 41% humidity, 1020mb pressure, wind speed of 4.6mph NW.
VTDA installed tests were done at 59F, 34% humidity, 1020mb pressure, wind speed of 4.6mph NW.
I did four 0-60mph runs on the stock airbox using the stock tune setings, then did four 0-60mph runs on the stock airbox and Stage 1 tune settings. I then did four 35-70mph runs on the stock airbox and the stock tune settings, and four 35-70mph runs on the stock airbox and Stage 1 tune settings. The average of each of the four runs was used as the basis for data comparison. None of the runs were done for pure speed or fastest time possible. Consistency was the goal, otherwise I would be recording human variables and not hardware variables. No power shifts, all shifts done at as close tot he same RPM as possible, throttle position as close as possible in all tests.
The same testing procedures were used for the VTDA after install (four runs each, stock tune and then Stage 1 tune).
On the stock tune from 0-60mph there was less than a tenth of a second difference in the average time on the stock airbox and the VTDA. On 35-70mph runs using the stock tune settings there was a 0.1s reduction in time from the stock airbox to the VTDA.
Using Stage 1 I found a full 0.2s reduction in 0-60mph times from the stock airbox to the VTDA. On the 35-70mph runs using Stage 1 settings there was a full 0.3s reduction in time.
As expected, there is little benefit on a stock vehicle as the engine does not NEED or have the ability to use much more air. Throttle response may be improved and sharper, and that is something I may examine when I get around to further tests. On Stage 1 the engine gets hungry for air and is starved by the restrictive stock box. I was able to confirm with glances at the screen during runs that boost was between 20-21psi peak. The ram intake style of the VTDA crams cold air right into the MAF. There's no empty space in a box that needs to fill up and stay full for the engine to suck through the filter. Air is simply crammed into the filter and down the pipe, forced by the speed of the car. It's possible larger turbos may benefit from an airbox enclosed style such as the AWE/Carbino and even the open BSH style open design as they may have the ability to suck in enough air to make a difference. I'll be sure to test that if I ever go K04 or Stage 3+ :lol: Either way, I would bet that a second VTDA design could be constructed with a larger filter that would feed larger turbos while maintaining the benefit of direct force feeding air, but that is just an idea.
For those wondering about noise, at speed you can't hear anything, windows up or down. Sitting in the garage and revving the engine there is a noticeable sound of blowoff/vent. Certainly less than I have heard on videos of other intakes, but still there. So sitting at a light showing off for the girls will be fine.
EDIT:After a longer test drive with both normal and spirited driving there is some vent noise on occasion. I first noticed it when I went to pass someone and then had to back off due to lane ending. In normal driving, you will not hear anything, but if you WANT to show off just accelerate hard for a few seconds and then back off the accelerator fast.
And here it is installed on my car. I need to keep my eye on that ridiculous SAI intake pipe. The only place I could find to zip tie it easily was to a water bypass hose and I am concerned about vibrations cutting it. I will clip off the excess of the zip tie after I firm up a location.
Yeah, like the color, but now I need to match a few more things without going overboard. Going to start with the engine cover. Will go with gloss black and matching blue on the cover. Not sure if I should go chrome, gunmetal, matching blue, or gloss black on the rear pipe. Have to Photoshop it and see. I will be applying one of the supplied ModShack stickers eventually as well as a Linux decal/stencil.
Overall, I have no regrets with this purchase and look forward to more testing and playing with it as work and school allow. At $265 shipped and powdercoated in my choice of color, this was the perfect intake for my wallet and performance needs. Tomorrow I will be going on a nice drive in the hills with my wife to play with the XDS settings and am looking forward to it with this intake installed.
Well, I had some issues with VAGCOM so my dream of beautiful graphs and logs was not to be. I could not get VAGCOM to record my 0-60 and 35-70 times while keeping a record of the other data (RPM, Intake temp, MAF pressure, Boost). It was one or the other. I assume this is due to my newness with the software and I am sure I will figure it out (or someone will post here and explain it LOL). So, hopefully, I will be able to complete my dreamed of testing at a later date.
But I do have some info and a review.......and I have pictures.
Let's start with the install. Package came VERY well protected with everything wrapped in bubble wrap and hardware in separate little baggies with labels. Also included were three ModShack decal/stickers and a K&N sticker. The VTDA itself was wrapped about 7 times in bubble wrap. Step by step instructions were also included and I have to be honest, other than the lack of a "flashy" box, there was nothing that said "amateur". This was a professional presentation all the way.
There was a minor install issue and mistake in the instructions. Not sure if this is because I have a '12 and they changed something. The instructions state to use a T20 to remove the stock airduct from the grille. In reality, these are T25s. The T20 fit and seemed right until I got to the end of the first turn and it slipped. The clamps to attach the reducer were different. One was a bolt head and one was a flathead screwdriver, both were adjustable with a 5/16 open end though.
Install took about 20 minutes and was really pretty basic and easy. Intake is very secure mounted on two brackets at the front grille and supported on the rear using one of the OEM mounting locations.
Now, the IMPORTANT stuff. Performance. All test runs were done on the same stretch of road as each test. The 0-60mph runs were done on a back road near my house with smooth pavement. 35-70mph runs were done on the state highway nearby. AC was off, traction control was off. Baseline tests were done at 9AM-10AM, with VTDA installed tests done at 11:30-12:00.
Baseline tests were done at 55F, 41% humidity, 1020mb pressure, wind speed of 4.6mph NW.
VTDA installed tests were done at 59F, 34% humidity, 1020mb pressure, wind speed of 4.6mph NW.
I did four 0-60mph runs on the stock airbox using the stock tune setings, then did four 0-60mph runs on the stock airbox and Stage 1 tune settings. I then did four 35-70mph runs on the stock airbox and the stock tune settings, and four 35-70mph runs on the stock airbox and Stage 1 tune settings. The average of each of the four runs was used as the basis for data comparison. None of the runs were done for pure speed or fastest time possible. Consistency was the goal, otherwise I would be recording human variables and not hardware variables. No power shifts, all shifts done at as close tot he same RPM as possible, throttle position as close as possible in all tests.
The same testing procedures were used for the VTDA after install (four runs each, stock tune and then Stage 1 tune).
On the stock tune from 0-60mph there was less than a tenth of a second difference in the average time on the stock airbox and the VTDA. On 35-70mph runs using the stock tune settings there was a 0.1s reduction in time from the stock airbox to the VTDA.
Using Stage 1 I found a full 0.2s reduction in 0-60mph times from the stock airbox to the VTDA. On the 35-70mph runs using Stage 1 settings there was a full 0.3s reduction in time.
As expected, there is little benefit on a stock vehicle as the engine does not NEED or have the ability to use much more air. Throttle response may be improved and sharper, and that is something I may examine when I get around to further tests. On Stage 1 the engine gets hungry for air and is starved by the restrictive stock box. I was able to confirm with glances at the screen during runs that boost was between 20-21psi peak. The ram intake style of the VTDA crams cold air right into the MAF. There's no empty space in a box that needs to fill up and stay full for the engine to suck through the filter. Air is simply crammed into the filter and down the pipe, forced by the speed of the car. It's possible larger turbos may benefit from an airbox enclosed style such as the AWE/Carbino and even the open BSH style open design as they may have the ability to suck in enough air to make a difference. I'll be sure to test that if I ever go K04 or Stage 3+ :lol: Either way, I would bet that a second VTDA design could be constructed with a larger filter that would feed larger turbos while maintaining the benefit of direct force feeding air, but that is just an idea.
For those wondering about noise, at speed you can't hear anything, windows up or down. Sitting in the garage and revving the engine there is a noticeable sound of blowoff/vent. Certainly less than I have heard on videos of other intakes, but still there. So sitting at a light showing off for the girls will be fine.
EDIT:After a longer test drive with both normal and spirited driving there is some vent noise on occasion. I first noticed it when I went to pass someone and then had to back off due to lane ending. In normal driving, you will not hear anything, but if you WANT to show off just accelerate hard for a few seconds and then back off the accelerator fast.
And here it is installed on my car. I need to keep my eye on that ridiculous SAI intake pipe. The only place I could find to zip tie it easily was to a water bypass hose and I am concerned about vibrations cutting it. I will clip off the excess of the zip tie after I firm up a location.
Yeah, like the color, but now I need to match a few more things without going overboard. Going to start with the engine cover. Will go with gloss black and matching blue on the cover. Not sure if I should go chrome, gunmetal, matching blue, or gloss black on the rear pipe. Have to Photoshop it and see. I will be applying one of the supplied ModShack stickers eventually as well as a Linux decal/stencil.
Overall, I have no regrets with this purchase and look forward to more testing and playing with it as work and school allow. At $265 shipped and powdercoated in my choice of color, this was the perfect intake for my wallet and performance needs. Tomorrow I will be going on a nice drive in the hills with my wife to play with the XDS settings and am looking forward to it with this intake installed.
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