what do you base this claim on? 3 secs in 2.30+min (? which car did you use)

I used a GT3 car like MP4-12c GT3 lap times were 2:20 and 2:23 in newer and older configuration respectively.About spa,you should remember that it was a public road in the 90's so it was bumpy.It used concrete road rather than smooth tarmac of normal track.

If you think retarmicing doesn"t change laptimes,it changes a lot of things like surface grip

yes, but if you retarmac, it is because it got chopped and slower than when it has been first tarmaced and that brings back the same initial speed.

I have done some laptimes in both layouts in AC older version of spa was 3s slower

what do you base this claim on? 3 secs in 2.30+min (? which car did you use) circuit is very few and well within weather/track conditions/learning-the-track time fluctuations. it is quite difficult to establish with a reasonable certitude such a small gap. you need quite a number of consistent fast laps with exactly the same car/tires/parameters if these tests are taken years apart.

@manone
Just because track length is not changed doesn't mean it doesn't alter laptimes.Fogarty esses were around 80km/h corner before 2009 and now it is more than 120km/h corner,so it should change laptimes.

If you think retarmicing doesn"t change laptimes,it changes a lot of things like surface grip.I have done some laptimes in both layouts in AC older version of spa was 3s slower.Besides eau rouge,La source is also faster now,only bus stop chicane is faster than new chicane in that circuit.

Most of the F1 tracks are slower now but there are some exceptions like suzuka,brands hatch,etc.Suzuka was a bit bumpy in the 90's at some corners like 130r.

Chaning track layouts and especially changing them slightly, should be prohibited by law and made criminal offense!

Because it ruins the compar-ability of historical lap times. And we hate that.

@R8 LMS Ultra:
donington 2009-2010 chicane mod is ridicolous, the length of the the circuit did not even change by 1 meter. spa is slightly slower now than 1984-93, chicane is more twisty than bus-stop area. retarmac is just ordinary maintainance, you have to do it to mantain the same speed of the track.

essentially all f1-class tracks are now "slower" (meaning actual cars would lap faster in older configurations) than in the 80's because of the speeds cars were reaching back then.

@saxy
I know that fastest qualifying lap was by LMP1 but it was only 1s faster than GT1 so that makes it 4s faster than GTE cars,and it is not a small margin.GT3 cars qualify for 3:59 in 2015 aston martin festival.I think that modern LMP1 may do around 5:30s considering that they lap faster than Porsche 956 in lemans without chicane.

Imagine if GT1 cars are made with loose reg of 90's,they may be as fast as an LMP1.

The fastest qualifying lap in 1996 was by a prototype, not a Gt1 car. Different types of cars

The fastest CLk Merc had about the same pace as today's LMP2 (3:35-3:40 Le Mans lap) Which is similar to the group C cars (2:07-2:08 spa lap)

No one could imagine how much faster today's LMP1 cars would lap the ring

@saxy But remember 1997 and above GT1 cars were much faster than modern GT1.Their laptimes are even comparable to LMP2 cars.The GT1 cars were abolished in 1999 so in that year GT1 was not there,it was called GT Prototype.

In 1996 fastest qualifying lap time at Le Mans was 3:46.This year fastest qualifier was 3:51.That is 5s difference not a small difference.

You should also remember that Stefan Bellofs record could have been broken if late group c cars were raced like Sauber C11(possibly a sub 6) and even CLK GTR since it qualified faster than 956 at spa.Old generation group c cars are the only one GT3 cars are even close to.

Group C cars were always faster because of their enormous power to weight. some 600+hp in sub 900kg cars. compare that with ~500hp on 1200kg GT3 cars, it was always going to be a big difference. GT1 cars however have many different stages. Le mans for example. In 1996, the fastest GT1 lap was barely faster than this year's Ford GTE (~3:50). But by 1999, the GT1 aero/chassis got so much better, they were qualifying in the ~3:35s.
We've seen how powerful the late GT1s can be. The Maserati GT1 a few years ago did the hillclimb under 46s.

Yes,I am sure about Donington Claim,I don't know how to put the image directly,so look at the map in the link and observe the change in fogarty esses,it was made faster.
http://www.racingcircuits.info/europe/united-kingdom/donington-park/donington-park-pro.html#.V3Xo5YThntR

There are other tracks which were made faster like suzuka(4-5s faster now in my opinion),Brands hatch(removal of dingle dell chicane),Spa(better tarmac grip,faster Eau Rouge),Mid Ohio,Nogaro(wider road and new tarmac).

The majority of the hill is the 2nd half of the run. 92.7m elevation change. You can't see a hill? well it's either you have poor sight, or your english is poor.

question: what's the relevance of "goodwood hillclimb" when it is not an... hillclimb...(hemm... anybody sees an hill there?) and almost nobody takes that 50secs stroll as a competition?

@R8 LMS Ultra. two points to be made here: group c used one lap-lasting qualifying slick tires back in the days (+full ground effect); usually tracks are made slower as the time goes by, through new corners and making more twisty existing ones. Are you sure about your donington's claim?

i am not inferring that 2016 gt3s are as fast as group c, obviously, but car comparisons spanning various ages, even on the same track should be very careful.

@FL
To be honest I don't think GT cars should beat Purpose build racecars like group c cars,FIA GT1 in their prime.Their fastestlaps are much faster than GT Cars.LMP1 may beat it though.Have a look at donington laptimes.
Group C 1;15.281
GT1 90's 1:23.854
GT3 1:29.679
These times are taken from RSC website.
But then again esse at donington was made faster after 2009.
I think that P1 LM may be on slicks because it is almost as fast as a GT3 car last year.

Purpose build racers were on slicks and could barely beat some of the modern touring cars anyway. I think it plausable that LM wasnt on full (street illegal) slicks and it beat those racers with modern car stability, more stable power curve and aerodynamics which were no less impressive than those on many racecars.

Just look at the rear wing on that thing! And ride height is also as low as on any purposeful racecar.

I think its stability + predictability + more power + aero almost as good and not hat relevant in Goodwood + modern semislicks being damn good

Most likely the car was on slicks, because it is much heavier and with less downforce than the really purpose built hill climbers.

That's strange. Why did they run track-only P1 GT-R in Supercar Shootout and road legal LM in the main event? Maybe the LM was supposed to be in Supercar Shootout as well, but they changed their plans at last minute when it was obvious that it won't be possible to set meaningful times due to rain.

Knowing how cut-throat the hybrid-hypercar competition has become, I wouldn't be surprised if they equipped the LM with some trick track rubber.

obviously yes, road legal, but no statement about the tires:
http://www.motor1.com/news/64560/mclaren-p1-lm-took-down-the-goodwood-record-for-street-legal-cars/

Cool car and great driving anyway

Is that thinv road legal the LM? What about P1 GTR hat was ran in supercar class, is that road legal?

LM ran on Sunday when track was dry. It wasnt far from overall victory. But air temp was still cold and there was little chance of beating last years Subaru time.

The biggest problem with Goodoowd is the track is so short that tyres dont have any chance to heat up. And, obviously you dont get tyre blankets or anything like that.

What you need are some super mega-soft tyres that heat up and start working immediately.

It was funny to see how canam / group c / vintage f1 cars got beaten by wtcc cars, simply because most of those light sportscars couldnt get any grip.

Technically, the fastest was at 47.07s, the P1 LM. =)

not sure if it was running on slicks tho