Introduction. There are many people who race faster than the author at R Factor 2. I don't doubt that there are also many who are possibly better at setting up their cars. But as I'm pretty new and have just been through a rich learning curve that I am happy to share I did wonder if this little story might enlighten some drivers who are quite new to the sim and help them on their way. Its not written from the perspective of “hey I know it all” but more from “look what I just discovered”. So if you have much to learn please read on. If you already know a lot then it may waste your time. Thanks must go to the administrators at Race Department and the organisers of the RD Virtual World Endurance Championship who have given so generously of their time. Ill tidy this up a little more with some more specific setup parameters but will post it now as is for fun. Hope you like it. Background. Having freshly emigrated from the land of Xbox and games such as F1 2010 -2011 and Race Pro it was time to dive in the deep end with a top race sim. Of the 3 classes we decided to race the Nissan GTR GT1 as I had already done some club races in the Corvette C6 and some laps in the Nissan 370z without major problems. Previous encounters with the GTR however were disastrous. I just could not manage the car much at all. So I figured if I wanted a rich learning curve this car would give it to me. I put in an entry and approached 2 drivers who had shown interest in getting a race seat for the 3 race championship. While we awaited our acceptance it was time to do some testing. Setting up the car. Round 1 was to be held at Sepang Malaysia so that's where we started. Session 1: The search for initial pace: V1 Default setup. I know this track so it took only about 7 laps to get a representative time of 2:13.922 sec. I checked fuel use and it was 3.3 lit/lap. We need to know if we would be fuel or tyre limited on stint length. I tend to test on high fuel for a race setup. Observations: Need much better turn in and 6th gear was too long. Changes: To get better front grip and turn in lowered front springs from default. To 175. Also added some (1 click) front toe in. Rear camber just instinctively seemed a high number so lowered rear camber from -2.0 to -1.8 deg. Shortened 6th and spaced others fairly evenly. 1st gear was giving fairly high revs in the slower corners and helping a bit with engine braking. Checking tyre pressures the rears seemed too high* so lowered them from 136 to 128. *When checking tyre temps, as a rough guide the middle temp should be the average of the two outer temps. Its a bit challenging in RF2 as temps fluctuate a lot I haven't yet got a motec plugin to get this data stored so where on the track does one stop to check this? I was stopping mid way down main straight. Rears are set to minimum by now and still the middle temp is too hot. V2 lap time 2:11.429 (set on lap 2). Something was working and the first small step had been taken. Observations: Rear was unstable (“too loose” our American friends would say). Turn in still poor, fronts were locking up on hard braking. Changes: Reduced diff lock on power from 35 to 30.# Lowered slow bump shock absorbers on rear by 1 click.## Front camber reduced from -3.5 to -3.3. Brake balance rearwards 3 clicks.### Discussion:This was an interesting set of choices for me as I was essentially trying to increase grip at both ends through differing means. Also by reducing diff lock I was making the rear less stable but the changes to shock absorbers and camber had the potential to make it more stable. #The easiest way I can explain the mysteries of diff lock is to ask you to consider a go kart. It has no diff so both rear wheels are rotating at the same speed. Result is the Kart wants to go straight. One technique employed to get it to turn in better is to lean to the outside. When I was first told to do this by a driver coach it made no sense to me but of course it gets the inside wheel even lighter and reduces its influence and tendency to keep you going straight. What a differential does is allow the inside and outside wheels to rotate at the differing speeds that allow you to corner. If however they can differ totally and completely the rear becomes unstable. More diff lock on power side will give you stability on throttle (less oversteer), less will enhance turn in (more oversteer). On the coast side it has the same effect but under brakes. ## Slow bump/rebound shock absorbers influence the chassis ability to sink onto the axles. If you consider that the chassis is hung at the 4 corners and oscillating around. The stiffer the slow bump is set the harder they resist it settling with weight transfer onto a given axle. So if you want more rear grip you want the car to settle onto that axle sooner and for longer therefore you reduce slow bump/rebound (and or springs) on that axle. In this case I wanted to get the rear stable so lowered the rear setting. ### To set brake balance I'll do some hard braking with tyre temps visible and or watch the replay from outside the car to see which end is locking up first.then move balance away from that end. V3 lap time 2:08.411 (set on lap 2). Observations: Cars balance is improving but still appears to lack grip. Changes: Softened all springs V4 lap time 2:07.5 Observations: Softer springs increased overall grip. Changes: Lowered ride height.#### V5 Lap time 2:06.286. At this stage we run a tyre degradation test of about 16 laps. Fronts are red @ 12 laps and grip drops off sharply. Changes: Reduced rear camber further to -1.5. Observations:It feels llovely, a little oversteery but controllable. Easy to place the car but it's slower! Loss of rear grip can be misleading. The front can appear to be turning in better as it creates oversteer. So we run a 10 lap test with full tanks with each setting. Camber of -1.8 is faster. At this point we are a bit test weary so run a 1 hour race against AI. Managed to have better front tyre life (by initial standards that is!). Can now run to 14 laps with good front tyre performance. We then digress to a Wet setup session. Changes: Springs 3 clicks softer all round. Detached rear ARB. Its 2.0 sec faster than the dry setup. We then try front camber reduction from -3.3 to -3.1. Turn in discernibly better Lap time -1.495 sec. (This prompts me to remember to try less front camber in the dry.) Other jobs I put on the to do list: Test lower front camber in the dry. Compare front tyre life in the dry with and without TCS.*** Look for a compromise wet/dry setup. Do a full tank tyre endurance run to get some data to help determine stint length. No small commitment. It's an hour stint of consistent driving. Do a long run wet test. ***With no TCS the rears will spin just that little bit with throttle input which can allow the rear end to come around in a controllable way and help point the car where you want to go. This balancing effect can be quite nice. When TCS kicks in this is lost. Our final race setup was faster on worn tyres without TCS than with it. Technique and the search for front tyre life: With a reasonable setup its time now to work a bit more on driving. We are still nuking the front tyres before the rears are even yellow! I do a 20 lap test working on fore-aft balance and not stressing the front tyres. Changes: Reduced front camber to -3.1 and front tyre pressures. More so on left front. Observations: Just as fast with lower camber and probably less wear. I now have 2 team mates who are either offering suggestions or testing the setup as it evolves. We run a full tank of fuel stint to record tyre degradation. Amazingly drain the tank and do 29.9 laps with still functioning front tyres! We are making progress. Data shows significant drop off in tyre performance after 21 laps and again at 24 laps. V6 lap times Averaging across a stint now2:08. The search for long run pace Tyre life and performance across a stint is now on the radar as a priority so most changes are taking an hour to test. My new team mate and soon to be #1 driver David Gronvalls suggests longer low gears (1 &2) due to instability on corner exit, caster @ 6.5 vs 5.5 and a lower steering lock to quieten down the steering a touch. All of these things work well. Changes: Caster from 5.5 to 6.5.Steering lock from 26 to 22, lengthened 1st and 2nd. Observations: Much more feel (FFB) and faster. (7.5 feels even better but is slower). The slower steering (lock) ratio makes the car more forgiving and recoverable in a tank slapper. The reduced slip angle also seems to aid stability. We must have been sawing at the wheel a bit before. V7 Changes: Diff lock on coast side down from 50-40. Front camber down to -3.0. Observations: High fuel pace is faster by 1 sec/lap. Even more in first 4-5 laps. On full fuel we are now touching the 2:05s for first 12 laps which feels like progress. V7 Lap times we are getting 2:05s for 12 laps. Then a drop off of 2-3 sec over next 12 laps. Final Changes: Version 8 Changes: Looking again for better pace and long stint tyre performance I figure that we have a very stable car now and we can try a little more reduction in diff lock. Dropped power and coast both by 5%. The rear is very planted and car never wants to swap ends at speed so looking for a little more oversteer in the fast corners we reduce rear wing from 33 to 30. Steering lock further reduced also 22 to 20. Observations: Now is where it got quite interesting. On the outlap on cold tyres the front grip/turn in was very noticeably better. This got me excited as I was pretty sure that if it was fast on cold tyres it would be fast on worn tyres too. I run a high fuel stint of 19 laps. From lap 3 we are in the 2:05s and still there at lap 19! Lap time delta across the whole stint is 1 sec only. Happy with that. The car feels crisp on fresh rubber but no faster than V7. However as the tyres wear the rears are now wearing too and this (and wing setting) is allowing the rear to come around that little bit more and the car is now pointing more where we want. You can feel that the tyres have wear but the cars balance feels much better on worn rubber. It seems that in earlier setups the fronts were doing a lot of work fighting the diff lock and once they were tired it was understeer city. I also test and observe that the setup is faster with TCS switched off. The TCS as noted above is preventing the desirable slight rear end slide on throttle and resulting oversteer. I pass the setup to my team mates David Gronvalls and Tom Endres for evaluation and feedback. They are happy so we lock it in as the race setup. I am looking forward to our pace in the second half of our stint. Strategy: While doing the first of the long run tests I started using a spreadsheet to calculate the time lost in the slower later laps of a stint vs the extra pit stop time that results from a shorter stint (and more stops). Having tested fuel stops of 1 litre, 20, 40 85 litres fuelling time seemed to be 7 sec setup then 5 litres/sec. The early tests had more pace drop off so it steered us to a 6 stop/7 stint strategy. The same calcs using the final setup may have yielded a different answer as the pace deg was much less and we were now getting a delta of less tha 1 sec per lap from the fastest to the slowest lap times across a stint. We stuck with a 24 lap stint as the next viable number was 28 and we just weren't sure we could do that 6 times safely. In case we find dry weather late in the race I prepare a fuel load and stint length spreadsheet for all periods from 165 mins from end. The Race David G runs a 2:03 in quali placing us P11 and the final GT1. We are 2 sec off the pace of the fastest cars. I wonder if their setups have the same long run mojo that ours has? David is disappointed with his pace but I'm not and we are where we need to be. In front of a nice gap to GT2 and out of the mayhem if GT1 teams get excited early on. David drives an impeccable 1st stint,. He has done 30 laps including the formation and pace car laps. David mentions we lack top speed. We have been conservative on wing to get a safe car that is fast in sector 2 but maybe too safe. he gains places when he avoids an early skirmish in GT1 and hands the car to me in P6 Maybe we will do something today? I take over with the plan of staying safe. I'm a bit nervous and my lap times are very poor running 2:08s mostly. Top speed 247 kph. This causes issues as I am forced to fight GT2 cars for multiple laps before passing and the faster GT1s are soon to be lapping me. What is going on? Am I this crap? Lap 40 and an ambitious and impatient move by a GT1 (for which he has apologised) lapping us for the first time at the hairpin Turn 9 results in major damage. We pit for 4 mins for repairs. This is not good. P17 and 3 laps down. All Davids' good work gone. I later discover when watching the replay that my throttle has lost its calibration and I am only getting 90%. Not knowing but suspecting this I go into single player and reset it before my next stint. Tom runs his stint and has one or two issues. I jump into the car at lap 86 for my second stint. I make a big error on the outlap spinning at the exit of T9 (this corner is bad luck for me today) on cold tyres and lose 25 sec as I wait for a break in traffic to allow me to extricate the car. Then some (comparative) magic happens. Full throttle is now available and the car has 253 kph and more grunt everywhere. I drop into the 2:06s then the 2:05s as confidence grows and a couple of 2:04s. On lap 93 the car in P3 and multiple laps ahead catches and eventually passes us but I run within a 1sec gap for a few laps. I was chasing a very good driver and holding him. I was doing it! The top drivers are running in the mid 2:02s so we are +2 sec. I can live with that heck its a long lap at Sepang you know! Lap 106 and I pit to hand the car to Tom. His wheel powers down and we lose 5 mins as he boots his PC, loads game and rejoins server. Once back in we suffer an automatic 10 min penalty for hitting ESC. We are now down about 13 laps and not only do we have 9 Corvette GT2s ahead of us but the class leading 370Z GT4 is 2 laps up. We aren't having that! We redo our fuel strategy and plan 2 X 50 min stints. Tom drives his stint hard and scores our fastest lap to date of 2:04.2.He gets us to +40 sec of the GT4. David G then gets in the car to bring it home. He has a chance to not only pass the GT4 but there is also a GT1 car 40 sec ahead. He gives chase but after initial gains of 1.5 sec/lap the GT1 responds. The final stint is a race and we are P9 in class. David does I think a 2:03.xx 10 laps from home a GT1 pits and we gain a place. My fuel spreadsheet did some good! We had beaten someone in our class on strategy and finish P8 in GT1. (but P17 overall). We had learned a lot and hope to do better and have more fun next race in Bahrain. PS If you are stuck with an Xbox and want to play with all this setup stuff then Race Pro is the game for you. Summary of changes Default on left /Our Race setup on right. Rear Aero 34/30 Brake bias 61/39 // 58.5/41.5 Brake pressure 100%/ 94% Steering lock 26 deg/ 20 deg Diff Lock Power 40%/25% Diff Lock Coast 50%/35% Preload 2 / 3 Tyre Pressures Fr left 145/150 Fr Right 145/145 Rear left 145/117 Rear Right 145/117 Springs Front 263/166Nm Rear 245/158 Nm Shock Absorbers Front Slow Bump6/4 Slow Rebound 6/4 Rear Slow Bump 6.5 Slow Rebound 6/5 (Fast bump unchanged) Ride Height Front 6.2/5.8 Rear 7.2/6.3 Camber Front -3.2/-3.0 Rear -2.2/-1.8 ARB Front 95Nm/80Nm rear unchanged. Castor 5.5/6.5 Toe in front 0.10 deg/0.15 deg. Rear unchanged.