Dynamic / Adaptive chassis control (DCC / ACC)

[WhiteJames]

Before pics with after pics following each photograph in sequence.
Before pics: Std OE GTI Springs.
After pics: Volkswagen geniune lowering OEM Driver Gear Sport Springs.
Before pics taken with iPhone 4 - so definition not as good. After pics taken with old Pentax Digital camera that still produces better quality photos than the iPhone 4.

Post 459 at page 21:

WHITE JAMES: Suspension & Wheel Reviews - Page 21 - VW GTI Forum / VW Rabbit Forum / VW R32 Forum / VW Golf Forum - Golfmkv.com

Cheers.
WJ

[WhiteJames]

Sydney to Bathurst Drive:

Interested to see how the Volkswagen genuine lowering OEM Driver Gear Sport Springs fared on a very ordinary predominately B-grade road drive with extended time in the saddle. The drive from Sydney to Bathurst for the Bathurst 12 hour endurance race qualifying is about 220km one-way, which takes about 3 hours to complete for a total drive of 440km and 6 hours return route. It’s a mix of city – freeway for the exit from Sydney metro, then majority B’grade country single-lane roadway with a surface dishing up predominantly low and med speed compression hits to the Golf GTI suspension. The surface from the Sydney’s Blue Mountains to Mount Panorama is quite bumpy. The Sydney to Bathurst route entails the use of all three Dynamic Chassis Control (DCC) modes during different parts of the route:

Normal DCC in the City and for a third of the rural B-grade road route.
Comfort DCC for about a third of the time on rough B-grade country only routes.
Sport DCC mode for the Blue Mountains twisting hill-climb and descent and freeway cruising.

• The Volkswagen Driver Gear (DG) Sport springs do a splendid job of improving the low speed compression ride reducing the small incessant vertical chassis movements. The original Golf GTI wasn’t so good in low speed small-bump ride compliance on this route and felt like it sat a tad bit too high for ride height esp. at the front end.
• The DG Sport springs made for a terser ride on the slightly larger small bumps up to medium sized compression bumps, with the DG Sport GTI bucking and dipping to a greater extent with greater chassis control than the original Golf GTI. In this respect the DG Sport has traded off mid-speed medium -bump ride comfort for an improvement in small-bump low speed compression ride comfort. Depends on whether you’re looking for a knobbly & fidgety low speed compression ride with some steering wheel nervousness inherent in with the original GTI springs ... or ... terser and nuggetty mid-size bump ride and compliance of the DG Sport springs.
• It’s worth noting that all three modes used in with the original Golf GTI springs at particular points in the Bathurst drive were also required to be used with the DG Sport Springs. The improvement or degradation in ride comfort & compliance has not changed a great deal with the change in springs.
• Overall the ride comfort of the DG Sport Springs –v- Original GTI Spring is no better or worse imo. Each is better in some areas to the detriment of another area and vice versa.
• The DG Sport springs have not eliminated the steering kickback that happens only occasionally on mid-corners bumps and corrugations of decent size. The kickback is more pronounced in Sport mode, as was the case with the original GTI springs. The MKV Golf GTI did not have this issue.
• Urban intersection junction ruts, water channels and driveway lips definitely feel firmer than the original GTI springs as pointed out by my passenger that occasionally rides with me on day trips.
• My infrequent passenger on the day couldn’t notice a great deal of difference between the DG Sport Springs and original GTI springs for ride comfort or compliance.
• My passenger and I did not tire of the DG Sport spring 3 hour drives in the morning or late afternoon. This is a good sign for longer extended interstate drives of 10 hours +. This is also the case with the steering that is not overly direct with DG Sport Springs. I can rest assured that the DG Sport springs ride will not drive me bonkers on long interstate trips.
• Ride Comfort in Normal and Comfort DCC was still good enough on the not so good B’grade roadways for my passenger to have a snooze. When it’s time to wake him up – just hit the Sport button to give a jolt or two.
• The DG Sport springs definitely offered an improved ride over the KW V3 coilovers on softer settings for country road driving. Remember, that the KW V3 are able to go up to 20% softer than the KW V1 or KW V2 and generally ride country roadways better than the equivalent Bilstein and H&R coilovers.
• 1-2 occupants in the DG Sport sprung GTI has it well & truly sitting perfectly for ride height imo.

On a side note:


Always good to include pics with each write-up. I’m sure you’ve seen enough pics of my GTI. Here are some pics of some more exotic metal. Just for R-Nick in Singapore running the Ohlins DFV / Driver Gear Sport combo on his GTI – Lamborghini race cars were also running Ohlins suspension. Have pics to prove so ... just take a look. Bathurst 12 hr race/qualifying well worth the 3 hour drive from Sydney. A lot cheaper for tickets than V8 Supercars, you’re able to get right into the pits, workshops and on-top of the pit-straight building for no extra charge – in addition to seeing an array of cars – 4cyl, 6cyl Boxer, V8, V10, 6cyl turbo and V12. Much more entertaining than just seeing a whole bunch of similar built V8 stock cars with different out skins.

See pics here: WHITE JAMES: Suspension & Wheel Reviews - Page 21 - VW GTI Forum / VW Rabbit Forum / VW R32 Forum / VW Golf Forum - Golfmkv.com

[russ83]

I just did this same drive yesterday in my new mk6 GTI with Acc. Sport mode was excellent around My Victoria, comfort mode excellent for the traffic I encountered through the single laned bottle neck roadworks area.

Very pleased with ACC, a good option well bought.

[WhiteJames]

One slight omission in the above list - Bathurst City ride comfort from Orginal (OE) Golf GTI Springs to Volkswagen Driver Gear Sport Springs:

• The Original Golf GTI springs in Bathurst CBD had the DCC in Comfort with me wanting to go down to 17 inch wheels/tyres to further eliminate the brittle & fidgety ride - even in Comfort DCC mode. The DG Sport Springs have improved the Bathurst City ride comfort, no longer necessitating DCC Comfort mode or a desire for smaller better riding 17 inch wheels/tyres. The DG Sport allowed for use of the harder DCC Normal mode with improved ride comfort and 18 inch wheels/tyres now provide enough comfort in Bathurst City - a remarkable improvement in this area with the DG Sport Springs.

Cheers
WJ

---------- Post added at 08:48 PM ---------- Previous post was at 08:20 PM ----------

H&R Sway Bars:

H&R Sway Bars are the bees knees for fine tuning the Golf chassis with ease. I believe that a set of small H&R (26mm/22mm) set on front soft and rear hard would further improve my DCC Golf GTI in terms of control and tuning out the slight understeer and working the tyre with greater effectiveness (i.e. camber roll). Drawbacks for me are how much harder they will work the electronic DCC dampers in terms of life, one wheel ride comfort, the front bar front end tightness on rough roads with skitishness & skipping on one wheel bumps and rear end inside wheel lift, and lastly wet conditions. Had the H&R bars on the MKV, still love them though. Just not convinced about putting them on atm as DCC electronic suspension helps contain body roll and pitch. H&R would work a treat on the non-DCC Golf GTI as the DG Sport Spring lower and stiffer set-up doesn't seem to utilise the rear sway bar to the same extent as the higher and softer Original (OE) Golf GTI springs.

Cheers.
WJ

[WhiteJames]

Here are the two main New South Wales RTA guideline documents that relate to suspension modifications. Generally ... nothing has really changed for light motor vehicle modifications. For owner certified upgrades/modifications ... the onus could be up to you to show that upgrades are within the ambit of the technicall guidelines. Only a recent change of the 5cm rule when lowering or lifting a motor vehicle has changed ... this relates moreso to 4WD's than passenger cars as passenger cars generally cannot go any lower or higher than 1/3rd of OE spring travel (110mm on GTI apparently). The RTA article 3.5 on Suspension covers any suspension modifications in detail as opposed to the other two guidelines. Most changes in the RTA legislation and rules are centred around heavily modified vehicles and owner/builder kit & replica motor vehicles ... which does not include about 99% of Volkswagen Golf owners. Having your TUV certification handy will not guarantee anything, but it otherwise generally help re: required OE manufacturer specs for load, travel, rebound, camber change at full compression & rebound, etc. My Volkswagen geniune lowering OEM Driver Sport springs are all within manufacturer's spec and do not appear to breach any RTA guideliness either.

3.5.2 Certification of suspension modifications

Certification of suspensionm odifications shall be treated as follows:

Minor modifications can be treated as "owner certified".
These are modifications which do not affect the basic geometry or load carrying members
of the suspension.

Examples are:

. additional or uprated anti roll bars;
. uprated shock absorbers and/or springs;
. altered vehicle ride height by no more than one third of the
manufacturer's suspension travel in the direction of the ride height
change;
. fitting of suspension assemblies which were options from the original
manufacturer for the particular make/model.

See WJ Suspension Thread for links to RTA guidelines:

WHITE JAMES: Suspension & Wheel Reviews - Page 22 - VW GTI Forum / VW Rabbit Forum / VW R32 Forum / VW Golf Forum - Golfmkv.com

Cheers
WJ

[WhiteJames]

In respect to Eibach Prokit -v- Eibach Sportline springs: Eibach Swaybars similar in size to small H&R sway bars (Eibach 26mm/23mm) are designed to work with the softer and higher Prokit Spring on soft/soft, For lower and harder Sportline Springs, swaybars are to be set on hard/hard - according to Eibach.com website.

I ran Eibach Prokit progressive rates springs + small H&R bars (26mm/22mm) on soft/soft initially and can confirm that the sway bars work well with the spring rate in the softer Eibach Prokit Spring as Eibach.com website advises.

Setting the rear H&R swaybar to hard position at times, on longer constant radius high speed corners (80kph & above), induced a bit of heave in the rear end.

Heave is when the sway bar yaw or slip overpowers the softer rear springs causing the rear end to heave up and down like pushing your foot down on the small boat in water - this reduces the fluency of the chassis during cornering, creating a bit of crudeness in the chassis ability to negotiate corners. Generally happens at higher speeds and is consistent with what Eibach state in their website.

I eliminated this heaving effect by swapping out the Eibach Prokit/Koni FSD combo for KW V3 coilovers, with higher spring rate front and rear, at the expense of losing chassis adjustability and foregiveness in the chassis tune (esp. in the wet), but gained fluency around longer higher speed corners with the stiffer KW springs, reducing the effect of the sway bar set on its harder setting.

The initial phase of heave, I believe, is twitch.

The standard Golf GTI with DCC has a bit of twitch in the chassis on longer and high speed contant radius corners, with the front and rear end twitching of chassis mid corner in creating front and rear sway bar slip against the springs/dampers. Imo the sway bars on the stock GTI are at the higher threshold of the standard OE original Golf GTI springs - this may also account for some of the restlessness & uneasiness on the highway at faster speeds, in addition to a higher OE damper to spring low speed compression/rebound rates.

The introduction of VW Driver Gear Sport springs has reduced or eliminated this twitching effect of the standard set-up (need more time in the new DG Sport set-up to be sure ... so will keep you posted in a longer-term review).

Wouldn't bother with the progressive rate strut springs after having the linear DG Sport springs ... stick with linear for best overall results imo. Progressive rate look good on paper, but are compromised on the street.

An upgrade sway bars f & r needs to take into consideration the quality of roadway driven on. The smoother the roadway - the bigger the sway bars; the rougher the roadway - the smaller the sway bar. Imo, adding sway-bars for me would be to work the tyres more effectively in all weather conditions & roadway texture, and dial out some inherent OE understeer, rather than for outright speed.

Cheers.
WJ

[WhiteJames]

In wrapping up the Volkswagen genuine lowering OEM Driver Gear Sport springs review, I have completed a Sydney (Cronulla) to Gold Coast return drive up and down the Pacific Highway. This comprises quite a variety of roadways that necessitated all three Dynamic Chassis Control (DCC) modes. How do the DG Sport springs fare over a 10 hour 900km drive each way?

• The standard springs in the DCC equipped Golf GTI are softer relative to the damping rate. This does help push the GTI up once the cornering process commences ... the higher rebound rate of the damper relative to spring rate has the damper responding fairly quickly to limit understeer ... but it does create a feeling of restlessness and uneasiness, and doesn’t do much when larger and harder high compression bumps are struck as the damper only has the capacity to overwhelm the soft OE spring rate in the low speed compression. This creates a feeling of raggedness over larger & hard bumps, troughs and patchwork sections of the roadway.
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• The DG Sport springs with higher spring rate, esp. at the front (see my prev. Post), does create added understeer on corner entry. Once the GTI has been cajoled into the corner, the higher spring rate relative to rear spring rate (compared to VWR Springs) improves traction from apex onwards when powering out of corners. The higher relative front spring rate improves as speed rises, creating a really stable little hot-hatch. The higher relative front end DG Sport spring rate would also work better with those wishing to run rear-only aftermarket sway bars imo.
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• Driving from Cronulla through the City and up along the Pacific Hwy through to Hornsby, the standard springs just didn’t feel right to me. The damping rate on the OE standard GTI springs felt like wearing shoes one size too large or not having your shoelaces done up tight. Sloppiness, nervousness, uneasiness and restlessness come to mind when driving from the Harbour Bridge along the Pacific Hwy to Hornsby at 60kph. The DG Sport spring eliminate this tendency making for a reassuring nicely controlled nuggetty type of ride at lower speeds.
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• The 10 hour journey covering 900km felt shorter on the DG Sport Springs. I’ve done this drive a number of times on the standard OE GTI springs. The DG Sport springs make it easier on the driver, creating the feeling that the drive was 25% or a couple of hundred kilometres shorter. The real test is whether you’d want to do the same drive all over again the following day ... in this respect, the DG Sport are fine in terms of ride comfort on extended interstate journeys.
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• 50-100kph acceleration bursts on pitted, patchworks and rutted B’grade roadways, winding out the GTI in Sport mode, showed less raggedness and less influence from the roadway imperfections with less torque-steer under more strenuous loads.
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• On a tangent ... fuel economy was slightly better than all over drives with the standard OE springs. Could it be the slightly lower ride height of the DG Sport springs, as I wasn’t driving for economy on this trip? The Blue-Motion Golf comes with lower ride height to improve aerodynamics, amongst other fuel saving features. This drive was 6.6 litres northbound and 6.8 litres per 100km southbound for an average each way run of 6.7 litres. On standard OE springs, I couldn’t do any better than 6.85 litres.
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• At lower speeds of about 60kph, the mid-range sized bumps and troughs does have the DG Sport springs exhibiting a greater amount of vertical movement. It’s never harsh or jarring with DCC and the ride is still much better than the sports aftermarket progressive rate sprung coilovers.
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• Haven’t measured the ride height, but the rear seems to have settled down a bit more than the front. Level pics are difficult to take as the DG Sport springs are very sensitive to variations on the ground. It very rare to have the GTI on perfectly flat ground. Parked kerbside has different heights from left to right. Generally ... ride height is about Golf R ... perhaps slightly lower at the front and slightly higher at the rear when rear is un-laden.
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• Sway Bars – on a grand touring trip, aftermarket sway bars aren’t required imo. Up to 8/10ths the standard GTI sway bars are fine and EDL/XDS helps steering into corners bob-cat style. Anymore than 8/10ths and a set of small aftermarket H&R sway bars would prove beneficial with the DG Sport springs. The higher relative front DG Sport spring (compared to VWR spring) with the larger German made front sway bars (H&R, Eibach, KW) would have a really deftly handling fwd esp. for high speed corners of grand touring. For driving on cruise control at 100kph on the open roadways, standard bars are fine with DG Sport springs providing added comfort for longer journeys.
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• In contrast to the old set-up on the previous MKV GTI ... the KW V3 on almost full soft settings ... the KW coilover were slightly underdamped in the low speed damping rates, getting progressively harder the harder and fast the KW coilover spring compressed. Rough concrete carriageways like that between Gosford and Newcastle was a killer on the KW V3 for ride comfort. The three Brunswick Bridges between Byron Bay and Tweed Heads showed the KW V3 to have supreme control with short and fast vertical movements over the Bridge joints. The DG Sport strut style spring on std DCC dampers are linear and do not provide the supreme control of the KW coilover kits, with vertical movements over the Bridges taking a tad longer with slower vertical movement, for improved ride comfort. Concrete roadways between Gosford and Newcastle on the DG Sport Springs provided much more comfort than the KW V3 on almost full soft. The KW V3 provided reasonable comfort for about 2/3rds the Sydney to Queensland journey, the DG Sport Springs were fabulous for 100% of the journey. In terms of comfort, pays to stick with a linear spring like the DG Sport.
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• On the way up I was running about 38psi tyre pressure. On the way down from Queensland, I ran about 40psi. It does make a difference to ride comfort on the DG Sport springs. 38psi provides an added comfort. 40psi and DCC in Sport mode has the DG Sport sprung GTI feeling that bit knobbly on the concrete sections of the roadway around Byron Bay and Newcastle. This suggests that the DG Sport springs are not overwhelming the standard DCC dampers.
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• A bit of trivia: The DG Sport springs for the MKV with EA888 motor (North America only) have less spring rate than the equivalent DG Sport MKV spring for the older EA113 motor. In other words, the EA888 weighs less than the EA113 motor. North America has the EA888 motor for the last 1-2 years of build for MKV GTI. AUS received the EA888 motor in the MK6 Golf GTI. Not only does the Golf R motor sit higher in the engine bay to accommodate the AWD gear, the EA113 appears to be also heavier.
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• The genuine Volkswagen lowering Driver Gear Sport springs are designed with spring rates in mind whereby a standard Golf TDI/GTI that is fully loaded over axles weights should be the same height as the equivalent Golf TDI/GTI on DG Sport springs. In other words, the short and lower DG Sport springs have to be harder to compensate for lower ride height, but will sink less under vehicle occupant weight. DG Sport springs are designed to meet the stringent Volkswagen OEM standard for an unloaded, partially loaded, and fully loaded Golf TDI/GTI. Not sure if this is the case with other makes of aftermarket springs.

Cheers.
WJ

[WhiteJames]

Taking the Golf GTI back to the Surfers Paradise, Queensland for the second time in as many months, gave me the opportunity to sample the DG Sport springs up through the hills from the Gold Coast to Springbrook. Roads are better quality and smoother than the Boat Shed run South of Sydney, with Springbrook offering a myriad of back to back turns climbing and descending the mountain range. This route showed the DG Sport springs to offer a tangible improvement in containing the weight of the motor & DSG Trans when shifting weight back & forth between bends in the roadway. The OE STD springs with DCC in Sport had the dampers providing a greater effect in attempting to contain the body movement & lean of the Golf GTI. DG provided a better match for DCC Sport mode and offered a rawer driver/machine connection. Understeer encountered on the earlier Boat Shed in the Sydney Royal National Park was not as prevalent on Queensland’s Springbrook route with a 20 kph higher speed limit. The DG offered a really planted, poised and sag free drive that worked the front tyres more efficiently on the climb uphill. I was very happy with the DG Sport springs on the Springbrook drive.

On the issue of tyres: Queensland M1 motorway on-off ramps show that, despite some initial understeer of the stiffer and less adjustable DG Sport springs (a’la Golf R), once turned into a constant radius corner, the DG Sport springs provide greater composure and less understeer, keeping all that weight up front composed and helping prevent positive camber roll on the outside front tyre. The GTI eventually pushes into slight to mild understeer in terms of chassis balance with the DG Sport springs, prior to any help from the XDS electronic diff. Again, very happy with the DG Sport spring in this regard.

I'm still changing the Dynamic Chassis Control DCC settings at the same locations as I did with the OE STD Golf GTI springs to either improve ride comfort or for a sporty drive depending on the roadway on the way up and down from Sydney to the Gold Coast. Other forums are stating that the DG Sport springs are about 8% firmer than the STD Golf GTI springs. Rough roadways in North New South Wales from Ballina to Grafton, have the DCC dampers in Comfort mode heating up a bit and losing some composure with added bounciness after about 1.5 hours of getting slammed on crap roadways.

Guys beatching about VWR being lower (and softer) than Volkswagen own DG Sport springs may want to consider how the Golf GTI looks with occupants on board ... or ... in my case ... about 40-50kg in the boot with no occupants as the pics below show. The rear end is starting to sag a bit with only a large full suitcase, a couple of laptops and couple of large bags of fruit in the boot of the GTI. I imagine the VWR springs would really be sagging in the rear end of the Mark 6 Golf GTI 4 door.

See pics:

WHITE JAMES: Suspension & Wheel Reviews - Page 23 - VW GTI Forum / VW Rabbit Forum / VW R32 Forum / VW Golf Forum - Golfmkv.com

Cheers
WJ

[WhiteJames]

After over 8 months and 10,000km + riding on the genuine Volkswagen Driver Gear Sport Springs, which includes two about 1000km each way interstate trips from New South Wales to Queensland & shorter Sydney to Canberra interstate trips, I’ve come to appreciate a few things re: DG Sport Springs.

My understanding is that the standard wheel alignment settings for the Golf GTI is zero camber at the front & - 1 degree negative camber at the rear. With some moderate lowering of about 1cm front & 0.5cm rear by installing the DG Sport springs, the camber at the front is just over - 1 degree negative & the rear has gone to 1.5 degree to 2.25 degrees (depends on which side of the GTI you measure). In other words, the lower ride height has added about- 1 degree of negative camber front & rear.

The added negative camber, in addition with the lower ride height & stiffer front DG Sport springs, aids turn-in bite and front end grip levels with less body-roll induced positive camber on the outside front wheel. The extra negative camber + lower & stiffer front end now has a tendency to work the rear end in a more lively fashion to help adjust the back end of the Golf GTI mid corner. Only talking very slight-minute differences –v- stock springs, but the front end is so much planted around flowing country B-grade roadways. The chassis is more stable when adjusting the angle of attack mid-corner, as I have found out when taking evasive action against trucks that run wide mid-corner around the Tweed-Byron Valley B-grade winding roadways recently.

Additionally ... the standard Golf GTI springs would not have offered the stability on the same roadways in the same conditions, and required greater effort on the driver’s part to cut a fine line between obstacles on the roadway & the roadway shoulder.

Reduced is the standard Golf GTI ride brittleness that was pervasive with the standard Golf GTI springs ... and that is with Dynamic Chassis Control (DCC) optioned on my GTI (when set on Normal mode). On the other hand, the DG Sport springs do create a bit more vertical movement around town at town speeds of 50kph to 80kph, but out on higher speed country B-grade roadways, the DG a fine re: ride comfort ... in fact they are better for low speed – secondary ride comfort compared to stock GTI springs (with DCC).

I found that running the tyre temps at factory minimum 38psi gives best results for ride comfort. Anything above 39psi for 1-2 occupants can create a bouncy ride in the Golf GTI equipped with DCC and limit front end grip to a degree. 39psi + also has a tendency to trip the tyre pressure warning indicator frequently at higher speeds on uneven concrete freeway ... this has happened a number of times in my GTI when 39psi + is used with 1-2 occupants. Had the same issue with standard GTI springs also.

The extra negative camber at the front & rear due to the lower ride height does not appear to have any negative impact on the tyre life ... my OE tyres are at 40,000km with another good 10,000km of touring left in them before striking the wear indicator markings.

No measurements have been taken since installation of the DG Sport Springs over 10,000km ago. I have included a couple of iPhone pics with about 30-40kgs of luggage in the boot (no occupants in car). Golf GTI is at the threshold of reverse rake with just luggage in the rear hatch. Occupants only make the rear sink further. Rear end looks to have settle a bit more than the front end over time.

Post #495 at WJ Suspension Thread for 2 x pics ... WHITE JAMES: Suspension & Wheel Reviews - Page 23 - VW GTI Forum / VW Rabbit Forum / VW R32 Forum / VW Golf Forum - Golfmkv.com

Cheers.
WJ

[watevs]

Hi all, I am about to purchase a mk6. It pretty much doesn't have any options installed. Does ACC really make a big difference ? . Another question , how hard or costly is it to get satnav installed ? Thanks in advance