phantasms

I love my Z06. I have over 21k miles on it and it's near perfect. The one thing that has long bugged me is the throttle lag. This means the moment I hit the pedal to the moment it reacts to my initial input. It's a silly thing to describe but it will be important later.

How could I fix this problem I thought. The car is like a supermodel with a hairy mole on her neck that you may or may not be able to see at times...but it's there. I bought and sold a CAI. I considered getting a ported Throttle Body but after much research decided against it. Then there's the tune option. I'm running a Diablo on a Tahoe and that helped with the throttle. For obvious reasons I was more hesitant to install it on the Z06. Then I heard about the Vitesse throttle controller. After some research I read nothing but rave reviews. However I couldn't figure out if this would truly fix the problem or simply be a type of band-aid. I had a JCW Mini in the past with a Sport button. When you pressed this button it made the throttle much more sensitive....more "sporty" I guess. Frankly I didn't like what it did. It simply gave it a non linear more aggressive throttle map. It was very artificial and made the car "feel" quicker but much less controllable when driving at 10 10ths...which I did all the time with that thing. I drive a Z06 but often miss my Mini...but that's another conversation.

Anyway for $179 the Vitesse seemed like a warranty safe way to go so I jumped on it.

Today, the coldest day of the year thus far with the tires reading "Frozen" I decided what a perfect time to make the throttle more aggressive. In addition I installed a suede shift boot and **** to match the wheel that will eventually go in. GM thanks again for not allowing me to get a suede wheel and stick because of the red interior. The install was very easy and straight forward. It was my first time working in the new garage so I took my sweet time. I ran the wires behind the carpet and put the device into the center console. The secondary box was placed behind the carpet and due to heat potential I wrapped everything in heat shield material. Overboard? Maybe. The final product can not be visually detected without looking in the center console.

Well how does it drive?

In brief:

1. It's awesome.
2. It doesn't actually fix the problem.
3. It may make you get better MPG
4. It won't make you any faster
5. You should buy it.

In long....

From the reviews I heard of people enjoying the settings SP5 through SP7 so I went with SP6 to start. SP0 is stock and SP9 is nearly on off switch for those who are new to the game. As I pulled out of the garage and went down the driveway it felt great and I was extremely excited. The more I drove the more reality struck. The car absolutely does feel faster. Instead of fixing the lag it feels more like you added 200hp and the lag is the same but less of an issue because of the "added power". Yes...of course this isn't adding any horsepower at all but that's how it feels. I was skeptical of this explanation before I bought it but it is simply the best way to describe the result. It feels like I bolted another blower on top of the blower already on there...especially when driving around side streets. On the highway I was able to play with the settings and really take note of what was actually changing. Even in SP9 there 100% is still lag. It's absolutely there and I'm curious what the definition of throttle lag is to the people who claim it got rid of it. However because it immediately puts you so artificially deep into the pedal the lag is less bothersome and less noticeable. However it's fully there for and the timing of the lag is exactly the same. It is very noticeable on the highway in 5th gear doing around 70mph. Come off throttle and dip in throttle...the lag persists. However it's immediately met with a huge rush instead of having to put your foot further into it. One thing that was interesting is, to answer someone who was asking, it does feel like when you come off the pedal it gets off the gas more immediately. Again, because of how this works this must only be how it feels and not actual truth. Probably because there's less pedal travel to get off the throttle may be the reason why it seems to be doing it faster. Of course this isn't going to help the throttle overrun issue that we all have experienced from time to time. On the highway I ended up enjoying SP5 the most.

About that MPG. This of course depends on how you drive your car. I put a lot of highway miles on the car and normally I'm driving around 80mph in 5th gear. Of course I could be in 7th or 6th but I prefer 5th just because the car feels tighter and the power feels more ready to go. With this installed, without even realizing it at first I saw that I naturally was cruising at 80mph in 6th gear. So while this won't make a huge difference it will make some difference that I'm cruising a gear up simply because the car feels as good as it did previously a gear lower. 100 miles a day a gear higher must add up to some savings. Of course this isn't why people buy this car but some people care about this kind of thing and I did find it an interesting side effect.

Now the bad (other than the fact it doesn't really fix the problem)...low speed cruising can be a bit jolty. SP5 and higher make the tip in of the throttle in lower gears feel like someone who is new at driving. It's very easy to feel the throttle go from 0% to 15-20% instantaneously. To me, it's not a good feeling. It's this little jolt that I could do without. You can feel the same coming of the throttle and it's almost as annoying. SP3 and below you can't really feel it and SP4 it's barely noticeable. If you're someone who just takes this car out on the weekend to romp on it you probably won't have a problem with it or care. But as I daily drive in parking lots, 25mph speed limits...etc it's a bit annoying.

In the end I'd say that even though it does not fix the lag it's a great mod. It absolutely makes the lag less noticeable and bothersome. It may increase MPG. It overall makes the car feel much stronger, especially when you're not on the highway. I could see how someone who is more of a novice at the drag strip may get a better launch with it. But if you know what you're doing and already are getting good 60 foots it will in no way improve your times. I have yet to run the car hard through winding roads [it was 0 degrees today] but I expect it will make the car feel easier to modulate and increase confidence. I will report back on this eventually. It makes the car feel more raw and more like an angry racecar for sure.

Considering the price is $179 and it doesn't effect the warranty it's a no brainer. I'm sure half of us have spent more than that on mods that don't actually do a thing. "Hey Pauly do you feel a difference with that [insert stupid mod here]?...I think so"

Any questions?

Best,
Gene

p.s. as you'll see in the photos I installed some felt on the sides of the buttons to greatly reduce the chance of something in the box hitting into the buttons while braking.

http://www.vitesse-motorsports.com/t...orvette-c7.htm

four0nefive

Great write up, curious why you decided against a ported tb.

Also, I love your garage!

C7/Z06 Man

Gene I don't want to rain on your parade at all but as been mention before the DiabloSport handheld tuner has a tune that picks the car up with more throttle percent than stock built into the tune but also a 0 to 20% throttle increase on top of that if you want more or just apply a throttle increase to the stock tune. So you could go a couple of percent at a time till it feels right and no extra stuff in the car to boot!

How's the Borla X-pipe working out? Did you notice any gain in vacuum at idle?

DLC7

3 Z06ZR1

I run around in tour mode but do notice much quicker response
in track mode.

phantasms

I had decided against it because it seemed that the general consensus was it makes little to no difference with the throttle lag. Also that to get the most out of it one should pair it with a CAI which I wasn't planning on doing again.

Thanks for the garage compliments. It's still getting worked on but it's finally nearing completion. Having a sweet garage is literally a dream come true for me.

No rain at all my man. As I have also previously mentioned I do have a DiabloSport installed on my wife's Tahoe and have set the throttle to 15 on there. My wife keeps asking me to set it to 20. With the Tahoe I've experienced none of the tip in jerk that I experience with the Vitesse although I wonder if it's due to the fact the power to weight ratio is very very different. Also, while I definitely do not want to start talking about Diablo warranty concerns we all must admit there is a certain risk that is being taken with the Diablo. I personally feel that it would probably be ok to use it on the Z but I also feel if **** really hit the fan and GM did a full autopsy that it would turn up. Yes I know about the engine replacement on the car that had Diablo. I've read a ton on it. That said, with 21k good hard miles my engine probably isn't going to let go at least for another 100k. After driving with the Vitesse I'll have to drive the Tahoe again to see if the Diablo really gets rid of the lag or simply boosts the throttle like the V. Funny enough I had decided to pull the trigger on the Diablo with the Z but when I went to their website to purchase another GM license for the unit their site was down. While it was down I stumbled upon the Vitesse and decided to hold off on the Diablo.

X-pipe was a birthday gift. Being that my birthday is tomorrow I'll soon be able to install it. It was supposed to be a surprise but the wife didn't realize the box would say Borla on the outside 3000 times.

*Please please please everyone do not turn this thread into a Diablo warranty discussion.*

I'm usually in Sport and Track and while it may be quicker than Tour it's still far more lag than is acceptable to me.

Best,
Gene

rflow306

Thanks for the write up.

I think you are correct about the lag, someone at the track with the Vitesse controller mentioned that while the ramp up to wide-open throttle is quicker the log still showed that from a dead stop the throttle percentage will not hit 100% till approximately 30 mph at least on the A8 cars.

Z06Vert

Is it this way for a reason? Just asking...

axr6

Thanks for the terrific write-up on the controller. Regarding the question about winding road performance I can chime in with my experiences:

I have the base model C7. I got the car knowing that I would never be satisfied with any factory suspension setup so, might as well start with the base and build from there.

I have gone through lowering the car, 3 sets of swaybars, 3 alignments and an extra set of shocks trying to get the handling to where I liked it. Still, for some nagging reasons, I was not fully satisfied with the handling. The best way to describe my problems; something had given me a nagging sense of anxiety in driving the car near its limits on narrow, winding canyon roads with big dropoffs on one side and vertical cliffs on the other. In my other, well tuned, fast cars I was not experiencing the same anxiety over the same roads.

Then, I installed the Vitesse controller. Great news; my anxieties vanished instantly. It became obvious that they were caused by the huge inaccuracies in the throttle tip-in as I was attempting to get back-on and modulate the throttle on apex exits. Having to push the throttle way down in search of the very exact, fine amounts of power, spending the extra milliseconds to do so, unbalanced the cornering behavior of the car enough to rob my confidence. As a result of my many years of racing experiences I always advised drivers that during cornering the throttle in high powered cars had to be treated as if "stepping on eggshells without breaking them. The Stingray entirely failed that requirement due to its unpredictable and crude throttle tip-in.

How well does it work over my winding roads? One indication was my wife's dramatic announcement following the first run with the Vitesse:

"I will never ride in your Stingray again" - she declared after remaining quiet for the period of the fast, yet very confident run. I call it, finally, mission accomplished. Now the Stingray can fully use its upgraded suspension, giving me fine control at every phase of cornering. BTW - I settled on SP5 as my favorite level.

Madsen

Gene, thanks for being a ginipig ��. And doing the write up. I had seen other comments by you on this product and decided to order one. Although it's not on my car yet, I'm anxious to install it.
When I do, I may lean on your generosity to tell me how to dismantle the areas necessary to install the controller in a clean way.

Your garage is great!!. Looks like your still moving in..��
I like that because most folks would finish the garage before tearing into their project car. It shows me your excitement for your car����

3 Z06ZR1

Maybe you need an update? Maybe try the dealer. Mine has no throttle lag esp in track mode.

axr6

I have to add that mine also does NOT have any appreciable lag. Of course, mine is the NA engine with CAI.

phantasms

I assure you that your car, even in track mode, has more lag than I find acceptable.

I haven't driven a base C7 since 2013 so I can't speak much for the differences between the Z06 and C7 but good to know.

phantasms

Many professional reviews of the car have said that it's a bit hairy on the edge. I always agreed with these views and I certainly hope that, like you, this improved throttle control will fix it.

My pleasure. I'd be happy to help but the information was easy to find. I used this thread: https://www.corvetteforum.com/forums...nger-dash.html and a PDF I found on changing shift ***** here. netwelding.com/reports_vette_info.htm

Feel free to PM or email me with any specific questions as you go.

Best,
Gene

tzoid9

The removal and installation instruction were really broken down quite well in a thread on the C7 Discussion Forum. If it's a simple as this member explained it, I very likely will try it myself! Check it out.....

https://www.corvetteforum.com/forums...ll-review.html

Phoenix64

I know your pain. Both the long throttle, and throttle lag drove me nuts on my C5 Z06 until I tuned it out with hp tuners.

The throttle lag you speak of is built into the tune, I've heard it called throttle smoothing as well. It has 3 purposes that I'm aware of.

1. It acts acts a sort of passive traction control, so you can use the throttle like an on off switch but the computer spreads out your input over x amount of time, call it the M Schumacher app.
2. It helps cover for the "active" engine components AFM, and cam phasing, that would otherwise make the engine feel like it had a lumpy power band. (not a factor for the C5 but if you delete the smoothing in a new 5.0L mustang the engines throttle response goes from smooth to lumpy and ratchety for lack of a better description)
3. It saves drivetrain wear by reducing your ability to shock it.

Unfortunately there is no way a box that basically simulates a larger pedal movement can get around the throttle smoothing.

One last note, if you ever do delete it your traction control won't work very well after. All those algorithms need that throttle smoothing to work properly.

Big Lebowski

Great write up Gene. Gorgeous garage, and as always your avatar makes me chuckle.

petecaballero

Gene, if you plan to eventually get a tune, would you still recommend doing this or just wait it out?

phantasms

Pete,

I'd definitely wait it out. Do the tune and see if it feels like you want it to. The good thing about the Vitesse is it's so damn cheap and easy to install.

Best,
Gene

VictorBarron

I don't know if this question has been answered before, I did look.
Will the Vitesse void the warranty?