SimRacing.org.uk

Season 30 - Fun - 69X - Le Mans

Lou Magjar made a disco fix for the beloved LeMans (http://srmz.net/index.php?showtopic=6222&#entry119319) track!
Let's test it with the 69X cars...
 
Most famous race in the world is probably the 24hours at Le Mans. It has also hosted several Grand Prix including the first ever - the French Grand Prix of 1906. The Grand Prix name ("Great Prize") referred to the prize of 45,000 French francs to the race winner. The franc was pegged to the gold at 0.290 grams per franc, which meant that the prize was worth 13 kg of gold!

You have free car choice and no limit shift+r

Race List	=	IGOR
Server	=	UKGPL_8
IP Address	=	look at IGOR
Race date	=	22-05-2016
GPL mod	=	69X
60fps patch used	=	60fpsV1
Track dir	=	bsarthe (ftp://ukgpl3.dyndns.org/Tracks/)
Qualification	=	20:45  UK time -> 45min
Race	=	race starts at ~21:30 UK time
Race length	=	~45 min -> 16 laps
Damage Model	=	INT
Replay	=	you will get here (https://www.sendspace.com/file/se78bv)

Please restrict chat to emergency messages only, including at the end of the race until ALL drivers still racing have crossed the line.
Using the "no letterbox" patch makes chat messages in car obsolete, so you better uncheck it in GPL options ;)


GLA and have FUN

ARGH, 69X...& I have no mods  :(

I love bsarthe or Le Mans (Tom Kristensen track)...please, change it to Org 67  ;D

There are many cars to see from history, and much to learn.  Try a new Mod for a new year?  8)

Sorry, I'm a bit rusty at this - I have tried to install the track, but it's saying I have no more room.  I deleted a track folder and removed it from the season67 ini, but it still says I have no room.  ???

try taking some tracks out of GP.INI and/or uncheck "add to gp.ini......" when you install it.

Thanks.  I did it via GEM.  :)

what is the password server?  ::)

hi - now for practice it is : 60fpsv1    If you are at 36, it is not 36fps v1. ;D

Hmmmmmmmmmm??

Applied the track fix.
Qually was fine.

Almost made the whole of the 1st lap and avoided all the usual carnage points and got a screen freeze approaching S?F line at end of the lap.  Not convinced that the "fix" has worked  :-\

UPDATE

second race was OK for me, but I guess that does not finally prove anything. Maybe we need a few more races with big grids?

started third, lost it and waited for the whole field to pass so was last, by the end of the first lap back up to fourth, just before I got to the line......screen freeze  :(
grats to AC, GT and finishers.
not sure the patch has worked.

Second frozen race this w/e.  ::)

On another note, why don't we race the 69Xs at circuits which need high downforce?  This is where they come to life.  Decent circuits like Brands, Dijon, Zolder, etc.

About to start lap 3, approaching the same spot (just before start/finish) where I'd been following Gareth when he disappeared the previous, I found myself staring at blank screen wondering if I should have tried the patch.

@%&*!

I tested the track Saturday. It was an improvement from what I experienced last summer. I did have one screen freeze Saturday.

Everything went fine until I followed Axel into Dunlop on lap 2, race 1. I destroyed my engine in Q2 so I wasn't able to post a time. Race 2, screen freeze again closing on Martin just after Maison Blanche.

My computer doesn't seem to like this track at all. :(

I installed the patch.

My apologies to Martin and Fran for the side by side contact. I was racing a little too close, but it was fun up until the contact. Neither incident caused any damage. Just lost time. As it turned out, I had a screen freeze a little later in the race anyway. (I installed the patch also).

@Ronnie
I wanted to test the track "disco fix" so I chose the 69X as the heaviest mod to prove the result...
In the Special Series we will do 69X on good tracks ;)

Shame it did not work...
But we made no such bad experiences with nbsarthe ::)

@Tommie
Is the trk file necessary for each driver or has it to be on the server only?

My car had no wings, so it was not possible to pass it on the straight  ::)
Still some nice acceleration fights out of Mulsanne  ;D

The trk file is necessary for each driver. It doesn't matter for us racers whether or not the server has the patch installed.

If the night version 'nbsarthe' works without freezes, you can try that trk out on the normal track. Just take the nbsarthe.trk out of the nbsarthe.dat, rename it to bsarthe.trk and place it in the bsarthe folder.

The first race was a joke with crashed cars scattered all round. Second race was much better although I got hit at Mulsanne in lap 1 which put me last. After that great racing with Martin and Clive right up until the finish line :) . Fun trying to outpower them on the straights :) .

Tommie.

This is the first time I've really felt the benefits of slipstreaming.  I was managing 193mph without it, and about 205mph with it!  Is the 69X modelling different from 67s in that respect?

Way different, the tow in 69X is quite ridiculous, IMO ;)

I'd say with 67s the tow only starts 40-60m behind...problem with GPL is it works that way, by how much distance behind...because less powered machines would benefit more from tow (in real life) they changed this for 65s back in the day...

But I have no clue they gave 69X this amount of distance tow...to me 65 and 67 have the most realistic tow effects (maybe 65's slightly too much distance, 67s slightly too little distance)...just my opinion of course ;)

60's cars were not aerodynamically perfect, and the 'tow' much larger than now.  Slipstream effect is made different for each carset, but which are correct?   I'd guess more than our '67s, and big 'wings' added more again to 69's. If you go look at 'films' at high speed tracks - Le Mans, Monza . . . .  slipstream was a big part of the action.  :nuke:

That's probably true, but the problem is GPL works with distance tow, not with differences in drag, or power...in real life, the bigger hole that is punched in the air, the bigger the tow. Also less power will add to the tow effect. (see NASCAR Tona/Dega for example)

I guess the modmakers tried to compensate with more distance to allow for more tow effect, but IMO they overdid it on most mods, while it's too little with original 67s...

Our physics experts nowadays, look carefully at original laptimes, to find tow, and no tow data.  Two things missing in this, are 50 year old onboard logging/telemetry, and extra variables for drag.  

We need a half dozen owners to gather at Le Sarthe, to gather nose to tail data.  Total laptime would then need to be adjusted, to be as close as possible to Stewart and Company.  But this new physics would make it a new Mod - maybe a 69y?  

The cars we drive in this Sim, are as close to the real ones as any Sim, with the tools available.  ;)

if any one has a 49b I can borrow ill do it. tho I hope you have it insured  ;D

It does not, it does, it does, it does not, and it does not respectively :p .

I'm a student mechanical engineer, and people aiding in the development of the new slipstream model are professors of universities, have flown fighter jets or were professional cyclers. We used our background to validate the lap-by-lap data we had of the 1966 Reims race, where Brabham was slipstreaming Bandini.

The 1965 cars have the exact same slipstream models as all the other mods. Because they have a slower top speed, tow is reduced. As you might know, slipstream is related to speed with a square formula, which means slipstream gets four times as strong when speeds are twice as high. But as said before, the physics of the 1965 mod and any other mod is all the same.

Compared to original 1967 Papyrus model, the strength of the tow is reduced. The length of the tow is increased.

The 1967 originals have the drag of the cars set too low, so they run the same laptimes at Monza compared to real life without the aid of tow.

I've had this discussion many times, we tested the new slipstream model extensively with the 1966 mod, until our data matched the Reims data. After it's implementation, we finally got the 1969 Monza style races were were missing out on previously. I know the draft can feel a bit strong, but aero is a thing that is difficult to comprehend sometimes. I mean, have you ever seen that Antonov freight plane fly? It weighs 640 tonnes and takes off at only twice the speed of what we were doing at Le Mans last night.

A Dutch cyclist holds the record for highest speed on flat land (no downhill). He got up to 167 mph on his own power slipstreaming a dragster fitted with a special windshield to aid in drafting. Drafting is used in track cycling where a guy on a moped brings the cyclist up to speed.

This confuses me, but at least we have something to argue/discuss when we travel to the British Isles ;D

PS: can you check your PM Tommie ;)