Sprint Booster accelarator pedal response improver.

[J44EAG]

More than just a few of us have previously noted, fly-by-wire throttle control systems can feel a bit flat particularly in standing start and slow speed driving situations.

The effect becomes a bit less noticeable with an electronic Power Train Control Module reflash which remaps the fueling and ignition system. These have a noticeable effect on power delivery and typically safely up power by around 10% and torque by 15%. A reflash is a tried and trusted method of unlocking a manufacturers standard "soft" electronic architecture.

Gas flowing inlet tracts, cylinder heads and exhaust systems also produce more power and torque. It all adds to a freer running engine.

All the above are great in their own way but new found grunt still requires normal accelerator control pedal movement of varying distances, ie the length of the pedal stroke...a pedal with a short fulcrum arm might feel more responsive but perhaps more jerky in action than a pedal with a long fulcrum arm. That might make a car feel sluggish and unresponsive. These descriptions though would perhaps though be more applicable to an old car equipped with a Bowden cable type throttle. On a modern car though, the electronics designer is the man who can preset the amount of throttle response speed simply by altering design parameters. Simple to him..but not for uninformed me!

A modern car is likely to be fly-by-wire technology with an electronic throttle potentiometer sending signals to the PTCM which again electronically signals the drive motor of the throttle body to open the throttle plate whilst at the same time sending and receiving signals from the other sensors found in quantity on a modern car. Some months ago I did wonder if it were possible to pep up signal response from the throttle pot which might help minimise the time delay for an electronic fuel injected engine to respond to a throttle pedal command input. If such an amplifier could be designed and built, then it struck me that a faster acting throttle pedal response could be possible. Note that this would not increase power or torque, just increase throttle pedal responsiveness. When I worked in an R&D house developing structural laminates, we used to call this type of brainstorming as "making dreams come true".

Then this evening I tripped over this ebay listing. The company seem quite plausible and market a simple insertion plug and play module which fits between the accelerator cable plug and the socket built onto the throttle pedal potentiometer. In effect the unit is an amplifier and is designed to speed up signaling times. It is priced at £169. There is a video contained in the listing which explains what the module is all about. This listing has peaked my interest and I wonder what others might think. What is offered to my engineering dominated brain is certainly feasible and possibly works as described. Lets face it, this type of electronic wizardry is perfectly feasible. Take a look. I would welcome some positive well informed opinion.

I believe in the world of Formula One and similar activities that the subject is known as telemetrics.

http://www.ebay.co.uk/itm/Sprint-Booste ... Sw9mFWMx-W

Mike K

[ptjs1]

Mike,

A really interesting subject and one where I'm sure we can all benefit from some feedback from some technical experts who really understand this subject.

To my rather ill-informed mind I think there are two issues here. One is the signal response time and the second is the voltage that is generated based on the throttle pedal position. Whilst I'm sure the Jaguar components are built to a price and could perhaps be upgraded, I'm not aware that anyone is selling a plug-in kit that really transforms the speed of the signal.

I believe that the SprintBooster (and a few other similar market offerings with more settings) work in a slightly different way. They don't improve the speed of the signal travelling from pedal to ecu to throttle. What they are doing is generating a different voltage map for the various throttle positions. So instead of generating, say, 1v at 1/4 pedal travel, it generates the 1v at, say, 1/8 pedal travel, and 1.25v at 1/4 pedal travel etc. The net effect is to open the throttle wider and at earlier points in the pedal travel. Throttle lag at low throttle movements would indeed be improved. There is one downside of that type of mapping which is that full throttle might now be mapped to say only 50%+ of pedal travel. This could result in a jerkier, more sudden throttle response and lack of finesse when backing off the throttle, particlurly at high throttle openings.

So, is there anything that we can do without spending any money on one of these voltage remapping kits? Well, there might be, but it really needs a Jaguar expert to confirm or correct my supposition.

We know that our cars can "lose" their mapping consistency slightly over time. I had a situation a few years ago where, after cleaning my MAF, I had a high idle at cold that always took a minute or two to settle to normal. It was suggested that my cleaning had now confused the car as to what revs were appropriate for zero throttle. Ian at XJK kindly talked me through a procedure which might help the situation. This involved "teaching" the car what positions equated to 0% and 100% pedal position and then training it to relearn 600rpm at 0% pedal.

Interestingly, I've read on a number of internet forums of a similar position to recalibrate the throttle voltage map on other manufacturer vehicles and thus lose some of the initial throttle lag. A lot of people seem to have had positive results from this. So, how is it done?

First of all, DON'T do this based just on my advice! I don't take any responsibility if it makes your car worse, idle high or have any other symptoms! But if you're curious, you could take a chance, like I did!

You turn on the ignition (don't start the car), wait for the usual warning lights to go out then smoothly depress the throttle to the floor past the kick-down position (take 2-3 seconds) then fully release it (some websites say to hold it fully down for 10 seconds before releasing). Then turn off the ignition. Then start the car. The car should now better understand 0% & 100% throttle travel and better utilise the standard voltage map. That in itself could improve throttle response.

(I did have to do one additional procedure to remove the high idle which was to start the car and then immediately "load it" by turning on aircon, fans, all lights and any other electrical load that I could muster. The car idle naturally dropped and it "relearnt" that 0% throttle = 600rpm)

So, could we go further? Well IF that procedure does work, what would happen if you redid the procedure but only pushed the pedal 1/2 way down? In theory, the car would think the pedal only had, say, 3" of pedal travel rather than 6" to go from 0% to 100%. This would then theoretically give the same result as the SprintBooster voltage remapping at zero cost! Am I right? We need some expert opinion!

Mike, has this piqued your interest and are you going to try it tomorrow??!!

Paul

[J44EAG]

No. Not yet.

What I am going to do is phone Gerald Morten at Viezu Berkshire and ping him the link. That could be very interesting indeed.

Mike

[ptjs1]

Mike,

I've now found a US website which confirms my belief on how the SprintBooster works. It doesn't seem to be their normal website which doesn't explain the principle. See here:

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

Paul

[J44EAG]

There you go! Essentially what I surmised in my first post.

So less pedal travel needed and less effort in maintaining a consistent speed, I would imagine. Perhaps even less pedal prodding which might help mpg?

Whether the benefits are worth £169 is another matter.

I`ll attempt to get a phone call in to the UK distributors and ask about suitability and correct plug/socket sizing. If I get a decent answer, I`ll ask for one to be used for review purposes....All in the persuite of science and the JEC membership in general!

Mike

[ptjs1]

Mike,

Hers' an alternative with more settings. Not really clear which XJ it fits. Why not try and get one of each for comparison purposes?

http://idriveaustralia.com.au/

Paul

[J44EAG]

It gets more interesting by the minute. There are several different manufacturers making these units, most of them American. As we know what appears in the States, eventually finds its way over to the UK.

There is little doubt that the Americans have a massive after-market industry and a huge amount of enthusiasm for tweaking and tuning. They were running multi-cylinder OHV units whilst in the UK, four cylinder side valves were the norm! Our own tuning establishment numbers are tiny compared to the number found in the States. If one were to ask how many supercharger manufacturers we have in the UK, I would be at a loss to name one. Ask the same question about USA made chargers and I could reel off probably ten without having to think too hard. If there is a need or a possibility, the Americans will have a head start on us by a mile. Remember they got to the Moon years ago and the space age electronics now available is a direct knock down from the NASA investment program. A throttle response module is hardly rocket science ( sort of pun) but the piggy back chip involved probably has its roots back in the space program. Is it any wonder then that Jaguar went to the States to source the Eaton superchargers that we now see on our Jaguar R models.

Looking at several other throttle enhancer sales sites and a couple of You Tube videos, it becomes quite obvious that Sprint Booster and other makes appear to have passed us by in the UK and our knowledge that such units exist is possibly almost totally non existent. Only tonight have I become aware that this type of unit is available and that it is extremely popular elsewhere in the World. It cannot be regarded as snake oil in any way. Seemingly these modules work and are very common. The speed of signalling has been increased and that`s pretty much all there is to such a unit.

Pedal Box is another maker that I tripped over. I saw one of those units for 199Euro.

As far as the Sprint Booster is concerned, it offers the Green mode as an every day program which is soft enough in response for town driving, with the Red program being suited for fast driving but not suitable for town work.

I think I may well be interested in obtaining one of these units but I have a few domestic and other bills to take care of before belting the plastic card yet again!

The subject would make for good copy for the magazine pages. Watch this space!

Mike

[davidr]

I have 2 cars that have fly by wire throttles.
Firstly my fairly new Volvo V70. When Sports mode is engaged the throttle response becomes much sharper and a given amount of pedal movement has a bigger effect on the throttle opening to make it more responsive to smaller movements when in the press ahead mood.
On the older hand, my ancient td5 Discovery will make the pedal much less responsive when the the transfer box is in low ratio so you can be much more progressive on the throttle when off-roading.
Just so you know that a switchable throttle response isn't a new idea!
Regards
David

[J44EAG]

Mmnn,

I have an admission. I`ve never used the sport button thingy because I`m a meany and only being able to get to fifth gear in sport could affect my tight wad wallet. I know, switch back to economy mode to engage sixth gear after a blast. I might press that button tomorrow and suffer the expense to see what happens. I`ve preferred to stay in economy mode and not wind the bejesus out of the engine and gearbox by hitting the red line. That`s not what I need on a car for long distance dashes.

Another admission is that I like long stroke power units rather that short stroke where you have to rev the nuts off them to get the grunt. After all, I`m running a road car not a circuit racer despite undertaking the recent tuning mods which have all been aimed at faster throttle response and slow speed torque. It will certainly be interesting to see whether the sport button sharpens up throttle response. The car is pretty good now after the mods so it might prove difficult to tell if there is any additional advantage in occasionally using the Energiser Bunny button.

As regards the Sprint Booster product, my interest lays in its technical abilities and effects. I really would like to give one a try.

Mike

[ptjs1]

Mike,

You might be able to have fun in Sport mode and not worry too much about your wallet! The ZF6HP26 is really quite a clever box with lots of features of which owners aren't really aware. For example, it rarely completely disables 6th gear when using Sport mode. On NA cars, it is still available up to 20% throttle opening and on SC cars it's available up to 35% throttle opening. So for most driving conditions you'll still have 6th gear. The only other time it completely disables it is if you are in Sport mode and the adaptive transmission learning moves the map to "SuperSport" mode (the most aggressive map). Then it locks out 6th gear until it moves to a different map.

The other helpful feature is when you select Sport mode and then turn on Cruise, it will drop out of Sport mode and when you cancel the Cruise, it will drop back in to Sport mode. It's a very clever transmission for its era.

I use the Sport button quite frequently, particularly when I need Point & Squirt overtaking on fastish single carriageway roads, the A16 from Spilsby to Boston being a case in point! I get quite used to turning the button on and off on any journey.

So do give it a try. It can transform your driving experience!

Paul

[J44EAG]

The sport button certainly gives a quicker driving experience all be it allowing higher RPM between gear changes. I can`t say I noticed a sharper throttle response though. My aim is as always to increase low down throttle response whilst keeping the car in economy mode as much as possible. I like a torque based power delivery as opposed to a high revving engine for normal road going conditions.

I`ve stuck my hand into my pocket and just bought a Sprint Booster unit. I phoned a couple of people in the company to discuss a discount but negotiations were made difficult by a slight language barrier. In the end I just bought the unit at the typical normal price. It would appear that the phone number for UK customer care gets patched through to an office in Greece where the company have their head quarters.

I paid direct to the site via Paypal and upped the delivery to DHL Express. My experiences with Royal Mail or Parcel Force have never been good, hence the £1.90 up-grade. Now awaiting delivery. Watch this space.

Mike

[J44EAG]

A couple of emails with Telematica this morning reveals that a new version of this product is due to come online next Tuesday with additional features which include being able to add to vehicle security. Apparently the throttle pedal circuitry can be completely disconnected from the Power Train Control module and therefore makes driving the car impossible. Another useful anti-theft facility.

The sales guy tells me he wishes me to review the new product rather than the old one. Quite understandable from a marketing stand point.

In preparation for this units arrival, I took a look at what has to be done to install to the car. Two pull centre clips are either end of the carpet section below the steering column roll trim panel. Those get removed using just your finger nails. The carpet gets pulled down and pushed towards the transmission tunnel. Ducking down under the column, the pedal unit is quite accessible. Two circular white switches are visible with a black flat cable and plug close by. Two squeeze tangs allow the black plug to be pulled out. If the Sprint Booster were here, it would just be inserted between the cable plug and the pedal socket. The Booster control fly lead would then be affixed where needed to allow it to run along the bottom of the trim roll and thence to the lower edge of the transmission tunnel trim. There is a gap under the trim where it overlaps the carpet. The fly cable is easily inserted along its length and the control switch can be fixed to any convenient position with a small piece of double sided mounting tape.

As usual, watching and waiting for a delivery.

Mike

[J44EAG]

In the meantime, a couple of images here of an X350R throttle pedal. I suspect the same part is also fitted to other 350 models.

This is the plug and socket detail. The two squeeze together ears can clearly be seen. Squeezed towards each other, the plug pulls out of the pedal.

Jaguar X350 throttle pedal - Copy.jpg (68.24KiB)Viewed 7110 times

Here is a Sprint Booster unit which is inserted between the pedal plug and socket. Plenty of room surrounds the back of the pedal unit so fitting should be easy.

Sprint Booster image.jpg (52.82KiB)Viewed 7110 times

The extra fly lead with push button switch is located anywhere suitable and convenient to the driver. Alongside the gear selector appears to be a good position.

Mike

[andypryce]

Interesting to see what difference it makes, particularly with a standing start which can be an issue sometimes....

[J44EAG]

Indeed, Andy.

One of the best things I did to help power delivery from a standing start ie the second or so interminable wait for power to become available, was to port out the cowhorn pressure manifold. The by-pass neck is incredibly constricted. It doesn`t take much to clear the excess metal with a die grinder. It is great fun as well because when you put the cowhorn back on the car power delivery is much more fluid and on on over run and back onto the throttle is much smoother. There are no costs involved other than to buy a die grinder kit and obtain a few stones, sanding barrels and a tungsten cutting burr. The Clark kit from Machine Mart is excellent value and is electric rather than air powered. It is around £45 and most of the MM stores have them on the shelf.

This is a great freeby mod to make with a noticeable end result. A couple of hours work on this part is all that is needed.

Mike