Sprint Booster

[n15m0]

So the last 30% of your throttle does nothing now?

I'm no expert still on this subject I just use it and it works for me. The way I look at it if my pedal is at 70% and I'm already at WOT then why would I need the rest of the 30%? Thats just my logic I might be way out.

Will - You're welcome. I didn't come in here to start a debate but rather share what I thought was a rather exciting experience I had in the hope others would experience it for themselves as well.

The SB is not about increasing performance or HP. Just like a Z-tube might make your car sound better and tougher, this thing makes your car Feel quicker all through the rev range. You can physically feel it!

Next person who tries this please post your experience.

Kthx.

[whtbox]

will this effect the Cruise Control?

[V35DRIVER]

i had one of these fitted to my car. THEY do nothing!

they are not a performance enhancer. its main job is to stiffen your acceletor , so when push the pedal its job is to make the pedal feel hard. And it hardly even done that.

Please dont bother with this product if your thinking about getting it to add performance to the car.

hOWEver if you do own a BMW they are suppose to work well with that car.

[n15m0]

i had one of these fitted to my car. THEY do nothing!

they are not a performance enhancer. its main job is to stiffen your acceletor , so when push the pedal its job is to make the pedal feel hard. And it hardly even done that.

Please dont bother with this product if your thinking about getting it to add performance to the car.

hOWEver if you do own a BMW they are suppose to work well with that car.

Hey Mark,

No offence but you should read my post carefully again as I stressed a few times this mod does NOT increase performance. Not sure which product you used but it does NOT stiffen the accelerator at all.

I have been warned however that there are some SB copies that come out of HK and not Greece that are a hit and miss. These are usually found on Ebay so buyer beware. Buy from a reputable distributor and you should be fine. I'm sure they would be more than happy to give you your money back if this indeed does NOTHING for your car. Also another thing I forgot to mention is the guy that sold it to me asked if my car was modded or stock...he mentioned the effects would be more noticeable on a stock car as opposed to one running a tuned or aftermarket ECU.

The evidence is out there if you do a search, thousands of people have used it and are raving about it.

As for cruise control, it shouldn't affect it as I've got cruise in the Merc as well.

[BLISTC]

i think this is just a placebo effect it has on the driver.

you think it is faster for pressing the pedal down 70% its at WOT, but when you push that other 30% down you wont get any extra gain.

[Kam-80]

It's not a placebo effect, if the unit is amplifying the signal sent from the pedal to the throttle body then it stands to reason the throttle body is opening faster than it does without the unit, so there should at least be a noticeable change in the feeling of the car. Having said that it sounds like there might be a number of detrimental effects as a trade-off. Firstly, you're giving up a degree of throttle sensitivity, which would be detrimental to lap-times in a track / autocross environment. It also sounds like your fuel consumption would go up, because any small movement of the pedal is opening the throttle body much wider than it otherwise would. Finally, if you were to try and look at results empirically I doubt it would be of any benefit to lap times, 0-100 times or 0-400 times.

[siu_loong_bao]

This device is like the "SPORT" mode button on my ex-Porsche...A big difference in response...With my Porsche Cayman S Sport, the SPORT Mode would stiffen the active suspension, increase throttle response and open a butterlfly valve in the exhaust for a 'more throaty' sound...And the whole experience was like driving a 'different' car....

Getting back to this device, I personally would not fork out the $465-ish to buy it...

On another note, I did a search and 'think' this device would do a similar thing (and control a whole heap of other stuff) for $25/$75...Obviously, I am no electronic techie, but worth someone trialling it for the benefit of all of us...

MAYBE I AM COMPLETELY WRONG with this device:

http://autospeed.com/cms/A_2115/article.html

I also believe an electronic techie out there can make one for a fraction of the price of the SPRINT BOOSTER (unless it is patented).

As usual, my 2 cents worth...

[colorado bulldog]

might be worth looking into...

[zei20l]

It's not a placebo effect, if the unit is amplifying the signal sent from the pedal to the throttle body then it stands to reason the throttle body is opening faster than it does without the unit, so there should at least be a noticeable change in the feeling of the car. Having said that it sounds like there might be a number of detrimental effects as a trade-off. Firstly, you're giving up a degree of throttle sensitivity, which would be detrimental to lap-times in a track / autocross environment. It also sounds like your fuel consumption would go up, because any small movement of the pedal is opening the throttle body much wider than it otherwise would. Finally, if you were to try and look at results empirically I doubt it would be of any benefit to lap times, 0-100 times or 0-400 times.

actually the throttle pedal isnt connected to the throttle body itself. does no one realise this??

the ecu interprets the signal from the pedal input. it then decides what is the best opening as per its programming. lets have a few examples:

Lets assume the car is a manual; If the engine is doing 2000rpm, and youre in X gear, you can put your foot to the floor and the ECU reads 100%, yet due to its programming, it will only open the throttle 30%. no matter how lightly or heavily you push that pedal, it will only open 30%. (im guessing the opening percentages)

again, lets assume a manual, 4000rpm in X gear, you put your foot to the floor, ECU reads 100% throttle input, but its programmed to not WOT till 5000rpm, so untill you hit 5000rpm. the throttle will only open as far as its programmed to do so.

there are many reasons for this, 1, saving your driveline; 2, its programmed to give maximum torque across the entire rev range; 3, to save fuel. im sure there are other reasons, but i cant be assed putting them here.

so, all these devices do is to trick the ECU into thinking you pushed the pedal further than you actually physically have. but rememeber what i said above? the ECU may not 'allow' the throttle body to open to WOT just because you told it to. and then you have - as mark perfectly described it!! - a placebo effect.

the only way to fix this problem is with a reflash, or an aftermarket ECU.

[zei20l]

one way to test this is to stick a camera in the intake to look at the TB. or put a vacuum gauge after the throttle body and watch it instead..........

youd be surprised how many cars are limited with this 'feature'. coming to mind is my fiat 500, my M35 stagea, my old accord euro, my mums liberty.........

[Kam-80]

actually the throttle pedal isnt connected to the throttle body itself. does no one realise this??

Actually, I think we all know the car is drive-by-wire, possibly by the fact there's no dirty big cable attached to the throttle body.

the ecu interprets the signal from the pedal input. it then decides what is the best opening as per its programming. lets have a few examples:

Lets assume the car is a manual; If the engine is doing 2000rpm, and youre in X gear, you can put your foot to the floor and the ECU reads 100%, yet due to its programming, it will only open the throttle 30%. no matter how lightly or heavily you push that pedal, it will only open 30%. (im guessing the opening percentages)

again, lets assume a manual, 4000rpm in X gear, you put your foot to the floor, ECU reads 100% throttle input, but its programmed to not WOT till 5000rpm, so untill you hit 5000rpm. the throttle will only open as far as its programmed to do so.

there are many reasons for this, 1, saving your driveline; 2, its programmed to give maximum torque across the entire rev range; 3, to save fuel. im sure there are other reasons, but i cant be assed putting them here.

so, all these devices do is to trick the ECU into thinking you pushed the pedal further than you actually physically have. but rememeber what i said above? the ECU may not 'allow' the throttle body to open to WOT just because you told it to. and then you have - as mark perfectly described it!! - a placebo effect.

the only way to fix this problem is with a reflash, or an aftermarket ECU.

Unless you actually know What the system actually does, i.e. you've seen the programming somewhere, then you're making some sweeping generalisations. Normally, what a drive-by-wire system actually does when you start to depress the pedal, is advance ignition timing one or two degrees, then as you depress the pedal more, it starts to open to throttle body return to the standard timing map. The ignition advance gives a slight increase in power & response without consuming fuel or generating emmissions. The sprint booster would bypass this stage entirely as the ECU now thinks the pedal is depressed further than it actually is.

You've also got to be joking if you're suggestin WOT doesn't occur until 5000rpm? The only time you will notice the throttle body does anything other than what you tell it to is at the rev-limit, where the throttle body will start to close. Non of the reflashes, Osiris, TechnoSqure, etc do anything do anything to the throttle body / accelerator programming. Haltech repalcement ECUs don't have a map setting for throttle input / throttle body opening either, so I'd be really interested in seeing exactly which ECUs or reflashes you're talking about?

one way to test this is to stick a camera in the intake to look at the TB. or put a vacuum gauge after the throttle body and watch it instead..........

youd be surprised how many cars are limited with this 'feature'. coming to mind is my fiat 500, my M35 stagea, my old accord euro, my mums liberty.........

Or maybe you could use a Haltech interceptor to read the return voltage signal from the throttle body to determine what opening it's at...oh wait, I've done that and OMG what a surprise, WOT on the pedal turns out to be WOT on the throttle body too!

Edited November 9, 2009 by Kam-80

[Kam-80]

Whoops double post...

Edited November 9, 2009 by Kam-80

[zei20l]

ok so if you get WOT when you push the pedal to the floor, tell me how the sprint booster 'works' then??

i also mention that those numbers were examples, just to prove my point. if im wrong, im happy to admit im wrong. no problems.

but clearly you have tested this already and someone can maybe confirm this. not that i think youre wrong, of course.

i think they are a stepper motor but there might be a POT up there to measure 0-5v from to confirm the location of the throttle to the ECU.

i didnt bring my wiring diagram with me, assuming that the M35 2.5L and 3.0L NA motors are the same as a V35.

[Kam-80]

On the Zed the wires on the throttle body are hard to access, as they're encased in a big plastic plug, but if you want to try and test it from there I think it's pin-1 on the plug. The throttle body is also said to be quite sensitive and doesn't like being fiddled with. If you have pin-out diagram for your ECU you should be able to either splice the wire or access it straight from the harness (it's pin 50 for my car's VQ35DE rev.up motor and there's a secondary sensor at pin 69). The throttle body's sensitivty is calibrated to the car (there's a calibration process that can be done by pressing / depressing the accelerator pedal in a certain sequence) but fully closed should be around 0.3V and WOT is in the high 4.6xV - 4.7xV.

The sprint booster works by intercepting the voltage signal generated by the accerlator pedal and increasing it by a factor. Accelerator pedal (ECU pin 90 on my car) is also 0-4.7xV with a linear relationship between voltage and how far down the pedal is depressed (I haven't tested this but the workshop manul diagram illustrates a straight line relationship between pedal position and voltage).

Ignition advance happens at very small throttle inputs above 0. The sprint booster tricks the ECU into skipping this step completely as the small inputs are amplified into larger throttle inputs, so the ECU starts opening the throttle body immediately. As you move through the accelerator pedal's range, the sprint booster continues to increase the voltage signal by whatever its pre-programming dictates; I read somewhere that the multiplication effect is reduced the closer you get to 5V so the effective increase in response you're feeling is more in the early range of pedal movement.

This is just conjecture at this stage, but I think the ECU also has multiple programmings for how quickly the accelerator pedal is being depressed as there are 2 sensors on the accelerator pedal that deliver varying voltages to the ECU. I'm not sure how, but I think it can tell by the voltage delta generated how quickly you're pushing the pedal. Again the sprint booster would negate any low-input mapping.

I learnt all this after installing the Haltech Interceptor on my car and trying to figure out why it was giving TPS CELs (I arrived at the conclusion that the Haltech intercept signal and return signal were marginally different and did a recalibration) only to realize that the current Interceptor doesn't support cam-phasing.

[zei20l]

so technically the sprint booster just pushes the pedal more than you do, thus giving you the effect the car is going faster

are you sure ignition advance is taken from the throttle input? i would have thought it was taken from the MAF input which would go up from the throttle opening due to the operator pushing it?

hang on, youre saying the haltech isnt 100% compatible? hmm interesting. i think there is an M35 owner having problems with his haltech also!

[Kam-80]

so technically the sprint booster just pushes the pedal more than you do, thus giving you the effect the car is going faster

Yeah you "feel" you're going faster because the throttle body is open more relative to the position of the accelerator pedal. It does give the impression of going faster, but 0-100, 0-400 would be identical and you might be slower around a track, depending on how finitely you drive the car with the throttle. With the Sprint Booster you'd probably pull a better result rolling 40-60, 80-100, etc, with the difference being the micro-micro-seconds it takes for a normal car to get to WOT and the amplified Sprint Booster signal to get you to WOT.

are you sure ignition advance is taken from the throttle input? i would have thought it was taken from the MAF input which would go up from the throttle opening due to the operator pushing it?

Only initially. Throttle input of about 1-5 percent (this is how they normally program drive-by-wire, not sure about VQ). The ECU detects slight throttle pressure, and advances ignition timing instead of opening the throttle body. The ignition advance gives about 1-2rwkw more power and the car accelerates veeeery slowly. It only does this from cruising and if you want to accellerate slowly. The reason for this is strictly for emmissions and fuel-consumption related, not performance. But you're right, normally ingnition timing is taken from a fixed 2D map that plots load & rpm points.

hang on, youre saying the haltech isnt 100% compatible? hmm interesting. i think there is an M35 owner having problems with his haltech also!

If you have a car that does cam-phase timing (or VCT, or whatever Nissan call it), the problem occurs because you tap the camshaft-position sensor and modify the signal to do ignition timing advance/retard. This works OK but I found after a while I got a CEL indicating CAM-phase-timing was not working correctly. So I think what happens is the ECU compares the signals from the crank-angle-sensor with the camshaft-position-sensor, notes that the signal timing is different and throws a CEL. (This is only with the interceptor, Haltech list cam-phase-timing as a feature on their full-replacement ECUs). I got my mechanics to ask Haltech but Haltech say it should work, but if you look at their compatible-cars list on the website, it only lists cars WITHOUT any form of VCT (like S13, S14 but not S15 and R32, R33 but not R34).

[Jetwreck]

only to realize that the current Interceptor doesn't support cam-phasing.

ah huh! So that would be why my car starts to loose power from 5,000rpm onwards and the shit's itself after 6,000rpm? Why would they get rid of cam -phasing?

[Kam-80]

The interceptor is too simple to support it, I think it would need to tap and adjust the crank-angle-sensor signal and adjust it so that it's in phase with the camshaft-position signals, that's an extra input/output and a bunch of extra programming. What I ended up doing was delete the entire ignition timing map on my interceptor and just use the fuel trim map (so it ends up working like a better resoultion SAFC). I've just bought a GReddy Emanage Ultimate with harness as it was the only interceptor I know of that can handle and adjust VCT cam-phasing. It's either that or buy a full replacement ECU for a whole lot more.

The hassle isn't really worth it on an NA VQ, as their factory timing is really good and you can only adjust by 1-2 degrees to suit 98RON petrol, so the net gain is only about 1-2rwkw through the rev-range, whereas you'll get an easy 5 - 8rwkw of top-end by tuning a leaner AFR than factory (not sure about VQDET engines though). I'll eventually be hanging a super-charger off the front of my engine, so need to be able to reliably retard ignition timing without the whole ECU lighting up the dash like a christmas tree

[iamhe77]

The Haltech 350z Platinum can work as a copgy back to the OE ECU instead of as a replacement if you have to stay with Haltech.

Good choice going with the eManage though (easier since you are in Melbourne as we have a few damn good tuners for it down here).

Edited November 11, 2009 by iamhe77

[zei20l]

so now im 100% glad i got the emanage ultimate.

im surprised the haltech does support the S14 but it doesnt support the S15. they have virtually the same motor! even the NA varieties were VTC equipped