37¾ Mile Isle Of Man Mountain Course - Conversion from GPL


Workshop: https://steamcommunity.com/sharedfiles/filedetails/?id=2261065561

Build History

This full length "37¾ Mile Isle Of Man Mountain Course" was built by Jim Pearson entirely from scratch over a period of 14 years from 2005. It is a totally different track to his much earlier "Abridged / Shortened" 20 km version.

It was released by him for the simulation Grand Prix Legends [ GPL ] in June 2019.

Jim's original PDF Readme , release files and three release videos are located here;

The release thread for GPL is located here;

Note: This track replicates the actual roads existing before Windy Corner and Brandish were opened up with much bigger radii in 2006.

Conversion Credits

Converted to rF2 by S.Victor(Xiang) with assistance from Corti(Andres).

I approached Jim in February 2020 and agreed to the conditions set out in his track Readme PDF [ See above ] He then gave me written permission to convert his track to rF2.

Amongst these conditions were assurances that the permission being granted would be limited to rF2 in this case and that no income would be derived or sought for the conversion.

Jim monitored development of this conversion throughout, providing some useful assistance as required. He has asked me to include his assessment of my work as follows;

" When approached by Xiang earlier this year, I was encouraged to grant him permission to convert my 37¾ Mile Isle Of Man Mountain Course GPL track to rF2, as he appeared to me to have the right combination of skills, dedication, high standards and respect for the original work that I was looking for.

My faith in him has been richly rewarded, as he has persevered to overcome many of the real technical difficulties inherent in translating a very complex and lengthy GPL track into a quite different rF2 rendering and surface model.

He has surpassed my expectations and I believe the results display and drive as well in rF2 as they do in GPL, the sim it was originally tailored to. I hope you enjoy the fruits of our collective labours and show due appreciation of Xiang's work on your behalf.

Credit is due!

Jim Pearson
October 2020. "

Track Info

Length: 60.72 KM / 37.75 Miles
Two configurations:
- Mountain Course,
- Mountain Mist, [ Which is the same track, but has patches of Ground Fog and Mountain Mist replicating two options available in the GPL track. ]
Max vehicle: 48
Real road (0.9-1.0m density) & 2.7%(10cm) crossfall
Hundreds street lights
Out lap timing support

Notes & Recommended Settings

Jim's original PDF Readme is highly recommended for a complete view and understanding of the original GPL track and design choices.

Draw Distance (similar to LOD):
IOM is designed specifically around Draw Distance for GPL cockpit view. Draw Distance(LOD) is important for optimization as well as showing or hiding road and scenery at proper designed distance.
RF2 conversion has kept same principle in mind. It means player with view other than cockpit may find that scenery or road sections appear too soon or in the air, due to the different camera position or LODMultiplier value. The recommended way to enjoy this track is through cockpit view.
Note, if a track piece appears in the mid of air along the forward driving direction while using cockpit view, it means the car mod is set on a higher LODMultiplier value than default 1.0 value. Additionally, the default value for Swingman view is 2.0, which also enables you to see further than the track LOD is designed for. However there is no way to enforce LODMultiplier value from track itself, the only fix is by editing car mod camera file.

Out lap timing:
The track supports immediate out lap timing. Timing starts when car exit pitlane.
It is important to note that at the beginning of each new session, driver must wait until session timer starts to count down (except race session), and only then click RACE button to go out of garage, otherwise timing won't work. Due to the length of the track and the special out lap timing mechanism, extra caution is needed for not over speeding in pitlane (60KPH). Receiving a penalty and then jumping back to garage will result immediate DQ after you exit pit the third time (everytime you exit pit from garage counts as a lap).

Road surface & Real road:
The track surface has been re-constructed with real road in mind, with 8 square subdivision across 7.4 meter wide surface. The new surface also includes around 2.7%(10cm) crossfall for extra realism.
Due to complexity and extreme length of the track, enabling real road will result longer loading time.

It is recommended to set weather to Default weather, or any Cloudy weather for varied illumination and immersion.
This track uses many skybox type of background, and the weather file has already set correctly to avoid white skybox bug.
However, in case of white skybox bug appears, you can fix it by: close RF2 first, then delete any AAIOM_MCs.wet & AAIOM_MISTs.wet file under “rFactor 2\UserData\player\Settings\3775mile_Isle_Of_Man” folder.
Note: the .wet file only affects Scripted Weather, and possible to manually editing 4 haze scale value.

The overly darkness of shadow was a concern from the beginning. With the new IBL shader, and a special IBL setting, soft shading and natural looking shadow is finally achieved. Player can still find some hardshadow (Jim created for original GPL version) which baked into road texture, and we feel that it is good to keep them.

Night lights:
Thanks to Corti's assistance, over 200 light sources are placed at various locations, for extra immersion and challenging night racing.

Collision wall:
Collision is based on terrain objects and special invisible objects, which covers most of the area. However, they will not save cars from any high speed crash.

In original GPL version, 2D flagger acts as marshal, and it was recreated in RF2 through digitalflag and startlight for extra nostalgia of the GPL era.

Billboards & Xboards tree:
Due to the different way of rendering between two sims as well as complexity, only a small amount trees were converted to Billboards.

Textures & Material:
The goal of this conversion has always been a faithful translation of original track, and thus most of assets that brought from the original version were unchanged. All road texture has been AI-upscaled for better resolution. New IBL shader is also used for 4000 materials, in order to achieve best results and preserve all the original texture details.

Trackside Cameras:
Cameras is converted directly from GPL, which are mostly static cameras, and works exactly same. However in order to fix an unknown crash bug with "Spectator Camera hotkey", we’ve converted all static cameras to tracking cameras.

Fuel usage:
Due to the track length, fuel estimate on setup page is not accurate.

Signpost Corner gap:
If you find yourself driving in mid air beyond the sand bag barrier of Signpost Corner, do not worry, it is not a bug.
This is a special design, as it is in GPL, in order to blend track surface smoothly with the skybox from afar.

Thanks to Jim's extensive assistance and support, as well as every friends' help!

Also posted at 397 forum.

Kenny Paton

That's amazing news, I never thought JP would ever allow this in any other game. Congratulations Xiang on what must have been quite an effort. I think I just might reinstall rF2 to drive this wonderful circuit.
Loved JP's Dundrod as well in GPL.
First of all thank you very much for this great track!
I'm sorry I didn't understand how to solve the problem of a track part in the air. It happened to me right towards the end (where there is a roundabout) with the BMW m8 gte, driving from the cockpit. The first 50 km all ok. Only at the end ... Can you help me? I don't speak english very well. Thanks l
Jim Pearson is a master on conveying sense of speed on all his tracks… all his tracks in GPL are master pieces. Big thanks to Jim, Xiang and Andres to bring this great circuit to rF2.

I love taking the March around this track… next will be the Eve F3’s… :):):):)

Durge Driven

Is that you B ? Makes for fun although as normal you need x amounts of Restarts for it to
come good. I accelerated AI let them make good rubber then set as static all sessions
Still get 1 stutter early in lap the rest is smooth
Let me know I make new room mod ( purchased all historic 3rd party DLC if you have them )

IOM update is out btw

How good is Nords with F3 as well


Only drama I have is CSW have tried 10 setups including Bwana's , did FFB meter with simhub
I think there is json edits I need I remember Mat gave me one for Fanatec GT2 and FFB
was amazing you could feel psi difference where stock it was like the CSW is now
Flat out feeling anything like it :(
Sure Durge I'm up for some lapping around IOM.
BTW do you mean subscribe to all historic 3rd party DLC. (I'm not aware of any historic Paid DLC).

Durge Driven

oi B ........Sorry meant tracks

Djursland F3 CT v1.00
Eifel Betonschleife v1.14 free
Eifel Südstrecke v1.17
Sandevoerde v1.10
Silkeborg F3 CT v1.05



Belgium Bridgehampton Isle of Man Italy Jarama Longford Monte Carlo Portland Riverside :barefoot:

Need Kyalami Rouen and Mount Panorama Historic ...I pay anything
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Durge Driven

You will get this message when joining may take 30 seconds so don't exit


The rubber is good enough and set static as a work around...ie: no lag or stutter

Not expecting any joiners for slowest car in rF2
If you rookie there is no rules or damage and auto gears and clutch
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Drove this track a few weeks back, it's great. Thank you for the conversion.

@Paul Jeffrey is this news worthy would you say?
Definitely newsworthy, a labour of love deserves a front page splash.
Guess it wasn't newsworthy after all. Not as newsworthy as ACC/iRacing/AMS2 hotfixes or community polls about light vs dark, anyway.
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