Quote:
Originally Posted by Captain Unknown GT4
Its pretty clear many do not care or got the know how to set GTS up right prior to test, We cant blame them as most are to keen to get the foto session right or are more keen to simultanius drag start 20 car on same time to get a cool film.
But then again its plenty who dont know what they are doing.
Motortrend for instace drove GTS on high street setting in figure 8 lap(here is prof) and thats wrong. Also the got wrong tire pressure on racetrack. Rear should not be higher than front pressure in a front engin car. Sport auto know exakt right tire pressure and it is 2.3 bar front and 2.1 bar rear(hot)
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BMW tire pressures posted on the door of the vehicle are what they are.
BMW specs for vehicles to UNDERSTEER at the limit.. .. a Lot.
! They do this with both tire pressures as well as with their selection of wheel and tire widths (by using a wider wheel and tire at the rear of the vehicle than the front).
For reference.. old school BMWs like the E30 M3 actually came with a square setup.... however BMW has been designing cars to understeer since they began using staggered wheel and tire setups on the E36 M3... Back in the mid 90s the rumor was that a vehicle that understeers is safer for the manufacturer with respect to potential litigation. )
So.. Most knowledgeable BMW enthusiasts (especially old school BMW fans) instantly REVERSE this process by using some or all of the following methods
- installing a square set up
- installing Camber plates for track duty
- adjusting tire pressures higher in the front and lower in the rear than the OEM settings... typically such that tire pressures in the front are a couple of PSI higher than the tire pressure in the rear.
This sort of custom setup is what the owner does.. but ...
should we expect that a test magazine should test the car as it is... straight out of the box... or should they do a bunch of setup. ? The same issues occur when measuring things like audio speakers, A/V systems, televisions... etc. .. should the reviewer set the item up to look/function the best.. or just test the item out of the box... just as it is made.
One method tests the OEM vehicle.
Another method strives to extract the optimum from the vehicle for the test.
Clearly.. it sounds like Sport Auto does take time to set up the vehicle. Thanks for pointing this out and creating the thread.
That all said.. One of the key issues for the M4 GTS is that it is a vehicle that *requires* setup. Therefore... it simply will not fare well in tests where it is tested with the out of the box settings, or by reviewers that are not familiar enough with the vehicle to make competent adjustments.
Quote:
Originally Posted by Captain Unknown GT4
Thanks!
As I Said I was close to buy that Z06. But did not, as friends had it and it Always get in to limp mode after a few laps on track. This is a fact, and I even try later on to get answer from the importer of these cars if and when they Will solve that issue. It went almost a year and I got no feedback. Evenually these days It may be solved, by bigger cooling from factory. I really dont know as I lose interesst back the.
I even told My vette salesman I only use My cars on track, and also drive there and home. He then told me at the time I should not buy the Z06 as several of their sold cars at the time hade this limp mode heat issue.
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@phatcat most corvettes are impressive out of the box.. Many have issues while running hard at the track. it became quickly apparent that if you track any C6 vette...that one needed to have a host of optional coolers (transmission and engine oil) added to the vehicle as " neccessory" item so that it won't fail. I've had an intermediate level student put his car into limp mode and eventually cooked the transmission in less than a day on a small twisty course at Barber Motorsports Park. Add all the coolers and it should be just fine.
While I am not as familiar with the C7.. I would say that your salesman definitely steered you in the correct direction, based on your usage.