GPL Engine Manager

Historical Accuracy?

Some people have expressed the opinion that swapping engines wasn't historically accurate. In many cases that's true, but GPL has always been an approximation of the 1967 season, not a totally faithful replica.

In fact, GPL lacks a number of cars that were in the real season, and some of the car/engine combinations that GEM allows actually did exist.

The Lotus 49 didn't race till Zandvoort, and the version of the Ferrari 312 modeled in GPL didn't appear till late in the season.

GPL hasn't got several of the lesser-known chassis, and it lacks various combinations of last year's chassis with castoff engines run by privateers. Assorted Lotus, BRM, and Cooper chassis ran with a variety of engines. Steve Smith swears there actually was a Cooper-Ferrari!

Nor does GPL have the Formula 2 car that Jacky Ickx put into 4th on the grid at the Nurburgring that year, or the Lotus 33-Climaxes used by Team Lotus in the early races - or Bruce McLaren's first F1 car, which used a destroked Indy Ford V-8 and bombed big time.

On the other hand, there actually was a Lotus-BRM in 1966; Jim Clark won the US Grand Prix with it.

And by 1969, Jack Brabham was using Cosworths in his chassis, as were just about everybody else except Ferrari and BRM. From 1968 on, BRM was using a V-12 that probably performed a lot like Gurney's '67 Weslake.

Yeah, a Brabham-Honda V12 is stretching it a bit. But I figure anyone who doesn't like the idea can stick to the standard GPL cars and let the rest of us play with our new toys!


One of the most useful utilities for GPL is GEM+ (GPL Environment Manager). GEM+ is descended from the GPL Engine Manager (GEM) but is vastly more useful.

GEM+ allows you to set virtually every option available in GPL, including many that must otherwise be set by editing core.ini with a text editor. With just a few clicks, you can set video and sound options (including those for George Smiley's Voodoo wrapper), choose the video rasterizer you want to use, adjust force feedback levels, choose the car and track you want to go to, adjust AI speed, and even choose the setups you want to use when you get to the track. If you want to use a different engine/chassis combination (see GPL Engine Manager below) you you can do that too.

It does all this in an elegantly designed, efficient, and practical Windows user interface.

Get GEM+ at

GPL Engine Manager - Ethical and Practical Considerations

Paul Thurston greated quite a stir in the GPL community with his GPL Engine Manager, which can be used to patch GPL so that any engine can be used in any chassis.

This presents the GPL enthusiast with many intriguing new possibilities, but among many online racers and offline hotlappers, it raised concerns about "cheating".

Hotlaps and Rankings

Now that engines can be swapped at will, how will racers know that the playing field is still level? The fact that the Engine Manager did not bring along the weights with the "replacement" engine exacerbates these concerns.

For example, suppose you did a new personal best in a "legal" Brabham-Repco, and submitted it to Schubi's hotlap page. Great! But what if someone else submitted a hotlap using the ultra-powerful Honda engine in the same lightweight Brabham chassis? The light, aerodynamically clean Brabham is fairly quick with the 360 hp Repco motor. With another 70 hp, how could it fail to slaughter the times set with its original engine?

Due to these concerns, Schubi has actually closed his superb hotlaps pages and won't be taking any more hot laps.

Many voiced similar concerns about GPLRank, but there the situation is different because that site is already necessarily based on the honor system. Fortunately, so far its owners have chosen to keep it open.

Online Racing

Similar concerns arose among those who enjoy racing online. In recent months racing on VROC has shown a noticable increase in participation. But with the release of the Engine Manager, many people became concerned that they would be racing against people using "illegal" combinations.

For example, if I'm driving a Cooper-Maserati, and someone else in a Cooper goes blasting by me, how do I know if he or she is using the same engine, and is therefore simply a better driver, or is using a Ferrari or a Weslake and is beating me on the strength of superior horsepower?

Some people expressed concern that this would bring about the end of GPL club racing, thinking that now no one could be sure that their fellow club members weren't "cheating" by using a better engine in their chassis.

To address these concerns, I have helped form a working group which is investigating ways to ensure that the playing field is level in races hosted and joined through VROC.

Some Good Things about Engine Swapping

The Engine Manager presents the GPL enthusiast with many intriguing new possibilities. How would the Cooper go with a Ferrari engine? What about a Brabham with a Cosworth?

Naming Conventions

What do we call these new combinations? How do we manage our lap records if we drive a "modified" car?

I've created a couple of new drivers, one for GP cars with "swapped" GP engines, called Alison Hine FL (FL stands for Formula Libre), and another for GP cars with an Advanced Trainer engine, called Alison Hine FD.

This way, my lap records with the standard cars are preserved. Also the setups for the new combinations will reside in the new drivers' setup folders.

Ron Ayton has proposed names for two of the new combinations:

FD - GP chassis, Advanced Trainer motor

FG - "Formula GMSS": GP chassis, Basic Trainer Motor.

I propose another:

FL - "Formula Libre": Any chassis, any motor.

How about the engine from an Advanced Trainer in a Grand Prix chassis, with its wider, more grippy tires? Or what about a GP engine in a Basic Trainer, with its skinny little tires? Wouldn't this give us a pretty good idea of what Juan Fangio and Stirling Moss had to cope with in 1955?

Some online racing clubs have eagerly embraced some of the new engine/chassis combinations, finding them more suitable for online racing than the configurations that came with GPL.

In particular, using bigger tires (GP chassis, which have fat tires) with the smaller engines (the Advanced or Basic Trainer engines) has really caught on in some clubs. I've driven the "Formula D" Ferrari - a GP Ferrari with an Advanced Trainer engine - and I have to say it was a total blast.


Personally, I have long felt that one of GPL's great strengths is its extensibility - the fact that it's proved possible to improve on the graphics and sounds it came with, and especially the fact that it's proved possible to add completely new tracks. This has extended GPL's playability and interest far beyond the norm for most computer games. (Of course, those of us who are fanatical about GPL know that it isn't a game, it's a way of life!)

By the same token, one of my major frustrations with GPL has been the fact that we can't add new cars to it. Yes, the original seven cars, nine engines, and three different tire configurations (GP, Advanced Trainer, and Basic Trainers all use different tire sizes) are great, and give more variety and a broader range of choice than most other serious racing sims.

But wouldn't it be great if we could get a Ford GT-40 or a Lotus 72 or a Williams-BMW turbo (or my personal favorite, a 427 Shelby Cobra) into GPL?

The GPL Engine Manager doesn't give us that, but it does give us an enormous new variety of chassis/engine combinations to explore. Some of these combinations are so different from what we had before that they are almost like brand new cars.


I'm very sad that Schubi has closed his site. Martin Granberg is working on finding ways to detect engine swaps in GPL Replay Analyser, and I hope he succeeds. Hopefully the VROC working group will be able to ensure the playing field is level in online races.

In the meantime, I hope everyone will explore some of the new combinations which GPL Engine Manager makes possible. I also hope that everyone racing online will honor the rules of their series and the wishes of the hosts of pickup races.

If the club or series or server allows certain combinations, great! I'm looking forward to running a Brabham-Cosworth or a Lotus-BRM in a "Formula Libre" race sometime soon.

On the other hand, if a series or a server restricts races to the original engine-chassis combinations, you can be sure I'll be using one of those - and I'm confident that the vast majority of GPL racers will too.

Get GPL Engine Manager at Ricardo Nunnini's GPL Foolishness.