its about 800.00 but it switches out your whole VB...


http://www.gtmotorsports.com/product...cat=262&page=2

 

I guess the results depend on the actual current throttle lag which in the case of a Mercedes is about .1 seconds behind pedal:

http://www.crosslake.net/~dbipes/spr...intBooster.pdf

Is the Infiniti throttle response really that slow or simply a matter of pedal movement which then becomes simply a physical trait of the operator. In this reference the pedal movement was measured at something like .2 seconds from zero to full throttle with .1 seconds added by the ECM (not the 1 second claimed). To me if this holds true then it really sounds similar to the original 'sensitive throttle' issue with the Infiniti that drives users to reflash.

 

this gizmo doesn’t have anything to do with transmission... and how fast the rpms climb won’t make you shift faster...

I don’t understand the reference to shifts.

 

I think the thought is if the system thinks you are at 100% throttle sooner than the transmission will kick down sooner.

The flaw in this logic from what I have read on what it is doing is that it simply makes the ecm believe that the throttle is depressed further than it is. How long does it take to push the throttle to the 100% position? In the Mercedes example that was about .2 seconds for the tester. The actual response time was .1 seconds to the physical movement of the throttle. In the article it mentioned that it exaggerared movement by 1.3% This means that you could gain about 25% of the .2 seconds or .05 seconds. This would also mean that the reverse is true as well although maybe a little bit different numbers (but close). That is when you release the throttle it would take longer to get to the setpoint representing zero depending on the sample time of the rest of the system.

If the car had a kick down switch then that means wide open throttle may actually be sensed prior to what the transmission itself senses it off of the switch.

To me on an Infiniti 2007 it this device sounds like the sensitive throttle issue prior to applying the so called 'fix'. In other words it comes down to feel not any real world performance increase. This of course is assuming that the device works the same basic way on the Infiniti.

 

^^^ I understand what you are saying…

Osiris is capable of opening the throttle plate at a percentage higher then OEM settings… iow, you can recalibrate it to open further for every increment of accelerator pedal position (so in a sense, it’s doing the same thing – or at least the same outcome)… it still doesn’t make the transmission shift faster.

I fail to see the value in the SB. IMO the “perceived” quicker acceleration is not worth the price point.

 

It just puts a different opening curve to the pedal until they are 100% open. Probably what people feel is it takes less pedal travel for the auto to start kicking down gears when the accel pedal is pushed down. On the 05 sedans, this was already pretty good. but on our old 03s (at least the external TCM versions), the lag is notically longer on upshifts and downshifts.

Perhaps the perception of the user might be dependant on the year they are installing this on.

But I agree, the price point isn't worth the benefits (especially when this device apparently removes the downshift safety feature that prevents you from going into too low of gear for a given rpm).

 

The VQ throttle program likes to open the throttle off idle a little too quick, that's why it's so hard to make a smooth first to second shift. If you plot the throttle position vs foot feed on an XY axis you will see an "S" curve on the plot. It rises quickly and then falls off a bit and then rises again at 2/3 trottle. I was hoping that this thing would realign the program to help with that.

 

When I went to the website I found it interesting in that it really never does tell you what the device does, even in the section dedicated to that question. They dance all around that question with statements about throttle lag due to fly by wire, etc. but don't state what appears to be the case from what others have stated and that it appears to simply multiply the input from the pedal to the ecm by a set value. This if true means that it has no other function such as changing the curve of the pedal input, etc. To me it looks like snake oil in its claims about lag and it adds a possible failure point in the system. For example without redundant channels what would occur if it failed during an important situation?

 

If you want quicker shifts and firm shirts, get a VB upgrade. It feels GREAT under WOT.

 

I've seen a a graph that supposed to show the oem DBW pedal curve vs the modfied one.

What I don't understand is how those that have a DBW that's too sensitive expect this device to help them. Unless you ask them to soften the curve. But that's contradictory to their typical purpose

 

http://www.sprintboostersales.com/whyitworks.cfm

 

yes, I was turned off by that too... when they first came out here pushing the gizmo, the first thing I did was go to the site to determine "how it worked" and "what is really does"... I understand proprietary information, but it was/is so vague that I was no longer interested.

Then there were a bunch of posts by the vendor quoting positive reviews - that was another red flag to me... why wouldn't he just link the source of the reviews or have the owner of the unit post a review... anyone could doctor up a bunch of quotes and post 'em (I'm not suggesting he did that, but who knows?)

for $100 or less, what's the harm in trying it out (it would be cheap enough to give it a whirl for the helluvit)... but they have this thing priced at a point that more solid information is expected.

 

it's just like the blitz controller. The only thing is with the blitz you can pick how aggressive it is.

It makes the throttle very sensitive. I only use it when I drag race to help get off the line quicker.

 

Well I guess I'm one of the lucky ones that does not need a scientific explanation about how this device works. I've had it installed for about a thousand miles now and I love it. There is a posibility that there are differences between the 03s and the later models. But on my 03 it makes a significant difference.

 

Note they are not showing the other end of the graph.

Does it really take a half second to put your pedal to the metal? The time difference appears to be only 25% on the top maximum and the graph doesn't show what 100% actually is as far as output for an Infiniti. That is while the signal may be ony 75% of max output the ECM may treat 75% for practical purposes as 100%.

But these are the quotes from the website with the graph:

----------

SprintBooster overcomes this throttle response delay for your vehicle by providing crisp, on-tap acceleration for whenever the driver demands it.

Get more from your vehicle, fit a SprintBooster today!

Results:

At low revs, the engine responds at approximately half the time in comparison to before.

The delay time whilst accelerating in 3rd and 4th gear and the engine in the mid-range, is almost zero.

Big differences in the higher rev range.

Improved response for downshifts and safer overtaking.

Overall safety and more fun on the road!

----------

The engine responds in half the time? Even if it was to take you .4 seconds to push the pedal all the way down (other test such as for a MB showed .2 seconds) then the difference in time for their 100% output on their graph would be less than .1 seconds between stock and SprintBooster. I figure in reality the .2 seconds sounds closer to the truth and maybe even slower than what many can do and therefore instead of .1 seconds we are only speaking of a .05 second difference.

What they don't show is the other end of the graph where the stock would drop to 0% faster than the SprintBooster. Does all of these claims above for throttle response from 0% to 100% still apply when going from 100% to 0%? Or would this be like Jay Lenos motorcycle with a gas turbine (or his new gas turbine car for that matter). That is for the motorcycle you have a spool up lag and have to plan ahead when passing and you have a spool down lag upon throttle closure when slowing down. To me it looks like any benefit the Sprint Booster may give to spool up time would be canceled by what occurs when you start to release the pedal just like the motorbike when you pull the throttle.

Now if you want to cancel this effect then to me the thing to do is to add a mechanical block so the pedal only moves 75% total so when you release the throttle you are releasing from a normal 75% position instead of 100%. For 10 bucks you could probably make this $300 box.

Again what about the possibility of failure. What happens if this doesn't have a two channel provision? What occurs if it fails and 100% of the signal is the output from the Sprint Booster?