This is an iconic track that every racing enthusiast will ultimately come to appreciate.
Given that "supercars" like the Lamborghini Aventador with it's 6.5L V12 with 690 HP can only barely break the 7 minute barrier here (The Lambo set a record 6:59.93 time in 2015) it is remarkable that the purpose built, but somewhat underpowered Renault 2.0 can get below 6:40. The Lambo's 220 MPH top speed also shows that good lap times on this track require BOTH speed and cornering grip.
The Renault 2.0 is a little slower than the Star Mazda here, but given the shortage of good hot lap videos on the FR 2.0 running here, the above video is quite useful. Don't get intimidated. My friend Mark Jarvis, of Carbon Racing, is one of the top Star Mazda drivers in iRacing's world. (Along with Wyatt Gooden.) The lines for the FR 2.0 are similar to those illustrated in the video for the Star Mazda.
To get fast here, study the video and study the track map. You will not reach your potential here until you have run 80-100 laps! That is 10-12 hours of intense practice. You will not reach your potential until you have memorized the track---the key to speed here is knowing where you are and how you need to set up for the next corner.
I have created a map with comments that may be helpful. You are welcome to download it, enlarge it, copy it, mark it up, whatever. Note the KM markers and the fact that the names of the sections are often shown on the Yamaha trackside signs. This will help you know where you are.
As far as set up is concerned, I think it appropriate to think of this track as a combination of Bathurst (Mount Panorama) and Watkins Glen. So my advice is to start with the setup you would use at Watkins Glen (Medium Downforce) and then as you become more comfortable, move to the set you used for Bathurst. Be sure you are using the TALL 7th gear---you need to reach 150 MPH + in three places.
Lap times will of course depend on weather, but I do have some data for Morning, 69F, Clear conditions. Eric Jaeger in the Precision Racing League has run a 6:36.x. Wyatt Gooden is a few seconds faster than that. I am a little slower than Eric with a 6:38.x after about 10 hours of practice.
After a few laps, with average competency, you should be able to break below 6:55.x. This is a pretty good time, especially if you can repeat it without losing control for several laps.
Depending on your skill level, more practice will get you below 6:50.00 after about 30-50 laps. Keep in mind that if you go off track and reset, whether back to pits or to a mid track section--your tires are cold and have low grip. You cannot reach maximum speed until your tires reach normal temps which generally takes 6 to 8 corners.
Generally, you will be able to easily "remember" all but the Section from Kallenhard to Galgenkopf as the rest of the track is pretty "conventional". So spend extra time practicing the Kallenhard to Glagenkopf section---lots of VERY TECHNICAL details as to lifting, braking, and throttle application points that must be remembered and that will dramatically affect your times. This is generally where you will find the speed to break below the 6:40.0 lap time.
Here are some "general tips":
Generally the red/white curbs are very unfriendly here. Avoid them until you have a reached a high level of competentcy.
The Carousels or Karussell (the Big one and the later Little one) are tricky--don't go in too fast, use a little "maintenance" throttle to hold the rear stable, and exit them in the same way you do any other corner--apply throttle ONLY as you unwind the steering.
It seems like almost every corner is faster taking a late apex. Taking an early apex will almost always put you off track.
There are lots of "blind" corners so identify a reference point to aim for.
Keep in mind that on down hill corners, you need to brake a little earlier, and on uphill corners a little later.
Do not make any sudden steering inputs.
If a tired old (65) man like me can memorize this track and drive it below a 6:40, then a younger man with good reflexes should easily find it possible to get below 6:45-6:50 here.
(If 6:36 is great (Almost Alien) keep in mind that 6:36 + 3% is a 6:48.x)
PS. My 6:40.x laps are on iSpeed as Donald Strout. Here is my 6:38.9 on YouTube.
With some expert coaching from Wyatt Gooden, here is a 6:35.65, three seconds faster! (Optimal is 6:34.42)