GT-R FAQs

This page contains Frequently Asked Questions specific to the GT-R. General FAQs are located here.

What is the GT-R?
It’s a replica of the Robertson Racing Doran GT that raced in the American Le Mans Series (ALMS) and climbed the podium at Le Mans in it’s only attempt there. It’s available with a choice of a fiberglass composite or carbon fiber body, and has the typical Superlite semi-monocoque chassis design that has won races and championships in other cars.

Can I drive it on the street?
Yes, although it is very low. You'll want to order the optional front end lift kit if you decide to make it street-legal. It's really a race car, and quite low, so be prepared for scrapes, and the bodywork damage that causes. We recommend you drive this only on the track, unless you make bodywork changes to raise the front splitter height, as several builders have done.

Where can I race it?
The GT-R can be raced in SCCA, in NASA, and probably, NARRA. It is also a great choice for informal track days at your local track. For SCCA, it would easily run in ITE (a regional enduro class), and SPO. NASA would class the car in Super Unlimited for racing, or with the right power/weight numbers, in the ST classes.  It’s also eligible for Time Trials, and would typically be in TTU. NARRA would probably accept the car in it’s GT classes, which would be a very competitive and fun class. Of course, the car would be eligible to run in airport runway races like the Texas Mile, and with careful planning, other land speed racing venues.

Are there options for the car?
There is a choice of material for the body (either fiberglass or carbon fiber), as well as other interior options like AC, a tub, etc. See the configuration tab for complete details. But the car comes pretty complete, including glass or hard-coated polycarbonate windshields, lights, windows, hinges, latches, handles, etc. You’ll need to provide drivetrain, tires, battery, etc.

How does this compare to the SL-C and other Superlite cars?
The GT-R is wider, longer and higher than the SL-C. It’s a great race or track car, with lots of room, where the SL-C can be a great street car or a serious race car. The SL-C has a smaller cockpit area; the GT-R has lots of interior room.

The GT-R runs in similar racing classes with the SL-C.

The replica GT40 cars that RCR make are very different than the GT-R. The original GT40s are relatively quite small compared to the GT-R.  That’s one of the reasons that the GT-R can fit almost anyone- there is lots of interior room, much more than the SL-C, or any of the GT40 variants.

The bigger size also means that there is more room in the engine bay, especially for tall engines with wide dimension, like the modern Ford OHC engines, including the supercharged versions.

Is it easy to build?
Because it’s a mostly race or track car, it’s easier to build than the SL-C, for example.  There is no interior finishing needed, no air conditioning (unless you want it for the street), no concern for storage, etc., so there is just less to manage in the build.

Like all the other Superlite cars, it’s designed to be built in a home shop or garage, with normal hand tools. You don’t need to do any welding or machining.

Because it is capable of very high speeds, it’s prudent to have your work checked out by a pro race shop before you hit the track or the street.  A good shop will be able to go over the car, and do an initial suspension setup if you aren’t totally comfortable doing it yourself.

 Is there a build manual?
One is in development.  But the car is simple to build, and if you are familiar with basic wiring and plumbing tasks, you’ll find it easy to assemble.

I’m a tall guy- am I really going to fit in the car?
The GT-R is the most spacious closed car we sell. You’ll likely have plenty of room, even if you are an NFL tackle. There is tremendous leg room, and the GT-R is taller than the SL-C or other Superlite cars, so there is plenty of headroom as well. If you are big, and or tall, this is the Superlite car for you.

What about forward visibility?
The GT-R has very good sightlines, especially for a track or race car. You’ll enjoy the view out of the car.

What does it cost?
Click on the configurator button on the GT-R page for complete details. You’ll need to provide tires, battery, drivetrain (see below for a discussion of drivetrain details and options), paint prep and paint if needed. 

Turnkey race cars are available from Superlite Cars on an individually quoted basis.

What engines will fit?
Because the GT-R is very spacious in the engine compartment, a wide range of engines can fit. In fact, almost any V8, specifically including the Ford modular motors, will fit fine. We expect that most of the GT-Rs will use either the Ford mod motors, or the ever-popular LS engines. But the car will support most any other popular engine. The factory even has adapters to allow a wide range of engine/transaxle combos as well. Call if you have something unusual in mind- we can generally make it work. It’s really up to you!

Is there a right-hand drive version?
Right-hand drive (RHD) will be an option later in the production queue. The RHD version will include a mirror-image RHD dash, the correct chassis offset, and the proper steering rack and column modifications. Call us if you require a right hand drive car. 

What about the gearbox?
Mid-engined cars like the GT-R typically use a transaxle, instead of a separate transmission, driveshaft and rear end. This simpler configuration also has intrinsically less drivetrain losses compared to a conventional transmission/driveshaft and rear end. It also has packaging advantages.  However, they also tend to cost more, and are somewhat more difficult to find.

That’s why we designed the GT-R to be able to use a wide variety of transaxles, across a very wide range of cost and performance. For example, at the low end, you can still get Porsche G50 transaxles from recyclers for under $4500, cleaned and setup for inversion in a mid-engined car. These are good for cars with up to 450 ft/lbs of torque, depending on their condition. A Porsche G50/52 from the ’89 turbo, is stronger, and will accept more power. Also at the lower range are new Porsche transaxles from the Cayman line that are available for around $7500. These are a great solution for engines with under 500 HP/500 TQ.

The Ricardo transaxles from the 2005-06 Ford GT cars are extremely robust, and routinely power 1000 HP cars. These are harder to find, and the clutch and starter are expensive, but they are bulletproof.  And of course they look correct and are easy to use with Ford engines.

The new G97 transaxles from the late Porsche turbos are also great transaxles, and have withstood 600 HP in the factory race SL-C, on the way to winning the 2011 NASA Super Unlimited National Championship.

Recently, Superlite has been able to provide new transaxles from Graziano, a well-known supplier to several supercar makers. These transaxles are brand new, capable of supporting 1000 HP in road applications, are designed for mid-engined applications (so they don’t need to be modified to run inverted as all the Porsche 911-based units do) and are even lighter than the previous gold standard transaxle (the Ricardo). Best of all, they are priced– to new Superlite buyers at the time of kit order– at about the same cost as a rebuilt Porsche transaxle.  With all-new technology, designed for mid-engined applications, OEM-levels of refinement and durability, these are a great solution to the transaxle dilemma.

Superlite has also made available a Porsche PDK-based 7-speed automatic transaxle that is typically sold with an LS3 engine that has been modified to work with the PDK. Contact them for more details if you require an automatic.

Finally, the GT-R will also accept racing transaxles, as from Hewland, Sadev, EMCO or XTRAC.  These are very expensive and have frequent rebuild cycles, but are designed for the rigors of racing, are usually sequential shift, and are relatively light.  These are really for racing purposes only.  Please contact the factory to discuss your application if you have a concern about transaxles for your new GT-R.

What does the GT-R weigh?
Every builder customizes their car, so there is no single answer. The original Robertson car weighed about 2700 lbs. per the class rules at the time, and the GT-R should be slightly lighter. Careful choice of wheels and tires will have an impact on final weight, as will the engine and transaxle.

Is the car safe?
No vehicle of any kind is risk free to operate. But we have tried to make the GT-R as safe as reasonably possible. One way is through active means: the GT-R is agile enough to get out of dangerous circumstances, so it can avoid them entirely, instead of just plowing into them. Really great brakes that were originally designed for much heavier cars help to slow the GT-R much more efficiently than regular cars, so there is a safety margin there as well.

The GT-R also has passive safety built in as well. For example, the fuel tank is located in the safest position possible- between very strong chassis members, in the middle of the car (instead of being at the front or rear of the car where it is more likely to be ruptured in an accident.) Driver and passenger sit well inside the car, much closer to the centerline to provide additional safety, compared to other cars that have the occupants’ bodies very close to the outside edge of the car.

The GT-R also comes with a 6-point “roof structure” (the lawyers don’t want us to call it a roll cage) that serves to add chassis stiffness and provide some protection in the event of a rollover. For track use, available door bars provide more side-intrusion protection, and can be fitted to street cars as well.

How fast is the Superlite GT-R?
It depends on weight, drivetrain and conditions. But with the popular GM LS7 engine, a Ricardo gearbox, Hoosier R6 tires, and an interior, we timed an SL-C at 10.4 in the ¼ mile at 132 MPH. That should be similar to the GT-R in terms of performance. It’s not really a drag car, but an experienced driver, and better setup could no doubt improve on that time. 0-to-60 numbers are in the 3.2 second range, depending on conditions. Top speed is a function of setup and drivetrain, but with enough power, and the right gearing, the car could easily do well over 200 MPH. The Ricardo transaxle is geared quite tall, with a theoretical top speed of about 257 MPH, assuming the engine had the power to pull it.