Super GT Trans-Am Car Builds

In its infancy, Trans Am was a production-based series that pitted makes and models from around the world against one another. That spirit, and the competition that comes from it, lives today in the Trans Am Super GT class. With some of the most liberal eligibility rules in North America, SGT welcomes a wide variety of makes and models -- promoting crossover from other professional series and club racing.  


Here at the IFCA we have embraced the SGT Class as the pinnacle of our interest in Trans-Am, replacing our Modern T/A class of cars.   It's a more natural fit since we don't have any actual Trans-Am cars in Forza.  Emulating the SGT cars is as close and as high performance as we get to actual Trans-Am cars for now.  Building and testing this new breed of cars has been much easier allowing for a closer BoP than ever before too.


With only a 4 race season the pressure to do well in each race will likely increase to levels beyond what our drivers are used to.  We hope this is a positive change because even if you do come up short, the next new season will always be just around the corner.  This quick turn around of seasons means that you won't have to wait for weeks to get a fresh start in the next season which can get extremely long if you are not doing well.


Season 10 Tracks

1.Watkins Glen full July 11th
2.Silverstone GP July 18th
3.Daytona 24hr night July 25th
4.COTA night Aug 1st


Season 10 Cars July 11th 7:00 PM EST

1	2018 Ford Mustang RTR Spec  5
2	2016 Cadillac ATS-V FE
3	2016 Porsche 911 GT3 RS
4	2015 McLaren 570S Coupe
5	2015 Mercedes-AMG GT S
6	2015 Corvette ZO6
7	2015 Dodge Challenger SRT Hellcat
8	2014 BMW M4 Coupe
9	2013 SRT Viper GTS
10	2007 Ferrai 430 Scuderia

Privateer Build (driver rating 1950.000 or higher)
2018 Ford Mustang RTR Spec  5
572hp/522tq/3105lbs S770

Race air filter
Race intake
Race fuel system
Race ignition
Sport exhaust
Race valves
Race engine block
Race oil cooler
Sport flywheel
Race brakes
Race suspension
Sport roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 345/25R20 - 325/25R20
Wheels Compomotive ML
Forza downforce front and rear


Factory Build (driver rating 1949.999 or lower)
2018 Ford Mustang RTR Spec  5
606hp/554tq/3020lbs S790

Race exhaust
Sport valves
Street Twin turbo
Sport flywheel
Race brakes
Race suspension
Antiroll bars come standard
Sport roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 355/25R20 - 335/25R20
Lightest wheels
Forza downforce front and rear






Privateer Build (driver rating 1950.000 or higher)
2016 Cadillac ATS-V FE
599hp/573tq/3053lbs S758

Race airfilter
Race ignition
Race exhaust
Race pistons
Race flywheel
Race brakes
Race suspension
Race antiroll bars
Race roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 345/25R18 - 315/30R18
Wheels Compomotive ML
Forza downforce comes standard


Factory Build (driver rating 1949.999 or lower)
2016 Cadillac ATS-V FE
645hp/617tq/3008lbs S777

Race airfilter
Race fuel system
Race ignition
Race exhaust
Race engine block
Race pistons
Race flywheel
Race brakes
Race suspension
Race antiroll bars
Race roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 355/25R18 - 325/25R18
Lightest wheels
Forza downforce comes standard






Privateer Build (driver rating 1950.000 or higher)
2016 Porsche 911 GT3 RS
513hp/352tq/3181lbs S780

Sport intake
Race flywheel
Race suspension (standard)
Race roll cage
Race clutch
Race trans
Race driveline
Race diff
Race tires 335/30R21 - 275/35R20
Compomotive wheels
Front Forza down force
Rear Forza down force (standard)


Factory Build (driver rating 1949.999 or lower)
2016 Porsche 911 GT3 RS
544hp/374tq/3140lbs S799

Race air filter
Race ignition
Race flywheel
Race suspension (standard)
Race roll cage
Race clutch
Race trans
Race driveline
Race diff
Race tires 345/30R21 - 285/35R20
Lightest wheels
Front Forza down force
Rear Forza down force (standard)




Privateer Build (driver rating 1950.000 or higher)
2015 McLaren 570S Coupe
562hp/442tq/3097lbs S773

Race flywheel
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race diff
Race tires 315/30R20 - 255/30R19
Wheels Compomotive ML
Forza down force front and rear


Factory Build (driver rating 1949.999 or lower)
2015 McLaren 570S Coupe
603hp/475tq/3061lbs S792

Race fuel system
Race ignition
Race flywheel
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race diff
Race tires 325/30R20 - 265/30R19
Lightest wheels
Forza down force front and rear





Privateer Build (driver rating 1950.000 or higher)
2015 Mercedes-AMG GT S
549hp/523tq/3007lbs S767

Race air filter
Race valves
Race engine block
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Race roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 335/25R20 - 275/35R19
Wheels Compomotive ML
Forza down force front and rear

Factory Build (driver rating 1949.999 or lower)
2015 Mercedes-AMG GT S
582hp/554tq/2936lbs S786

Race air filter
Race exhaust
Race valves
Race engine block
Race pistons
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Race roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 345/25R20 - 285/35R19
Lightest wheels
Forza down force front and rear







Privateer Build (driver rating 1950.000 or higher)
2015 Corvette ZO6
692hp/692tq/3584lbs S771

Race air filter
Race ignition
Race pistons
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race driveline
Race diff
Race tires (stock width)
Wheels Compomotive ML
Forza down force front and rear




Factory Build (driver rating 1949.999 or lower)
2015 Corvette ZO6
724hp/724tq/3481lbs S791

Race air filter
Race ignition
Race exhaust
Race valves
Race pistons
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race driveline
Race diff
Race tires 345/25R20 - 305/30R19
Lightest wheels
Forza down force front and rear





Privateer Build (driver rating 1950.000 or higher)
2015 Dodge Challenger SRT Hellcat
688hp/632tq/3480lbs S770

Widebody kit
Race air filter
Race exhaust
Sport valves
Homologation restrictor plate
Race flywheel
Race brakes
Race suspension
Race antiroll bars
Sport roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 355/30R20 - 325/35R20
Wheels Compomotive ML
Forza rear down force

Factory Build (driver rating 1949.999 or lower)
2015 Dodge Challenger SRT Hellcat
761hp/700tq/3419lbs S790

Widebody kit
Race air filter
Sport fuel system
Race ignition
Race exhaust
Race valves
Race engine block
Race pistons
Homologation restrictor plate
Race flywheel
Race brakes
Race suspension
Race antiroll bars
Sport roll cage
Race weight reduction
Race clutch
Race trans
Race driveline
Race diff
Race tires 355/30R20 - 325/35R20
Lightest wheels
Forza rear down force





Privateer Build (driver rating 1950.000 or higher)
2014 BMW M4 Coupe
637hp/599tq/2793lbs S769

Race air filter
Race fuel system
Race ignition
Race exhaust
Race valves
Race engine block
Race twin turbo
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Sport roll cage
Race weight reduction
Race clutch
Race trans
Race driveline (standard)
Race diff
Race tires 305/30R19 - 275/30R19
Wheels Compomotive ML
Forza down force front and rear

Factory Build (driver rating 1949.999 or lower)
2014 BMW M4 Coupe
698hp/612tq/2752lbs S786

Race air filter
Race fuel system
Race exhaust
Race cams
Race valves
Race engine block
Race twin turbo
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Sport roll cage
Race weight reduction
Race clutch
Race trans
Race driveline (standard)
Race diff
Race tires 305/30R19 - 275/30R19
Lightest wheels
Forza down force front and rear






Privateer Build (driver rating 1950.000 or higher)
2013 SRT Viper GTS
640hp/600tq/3290lbs S759

Race flywheel
Race brakes
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race drive line
Race diff
Race tires 355/30R19 - 295/30R18
Wheels Compomotive ML
Forza down force front and rear


Factory Build (driver rating 1949.999 or lower)
2013 SRT Viper GTS
683hp/640tq/3223lbs S778

Race air filter
Race intake
Race valves 
Race pistons
Race flywheel
Race brakes
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race drive line
Race diff
Race tires 365/30R19 - 305/30R18
Lightest wheels
Forza down force front and rear



Privateer Build (driver rating 1950.000 or higher)
2007 Ferrari 430 Scuderia
515hp/355tq/3028lbs S760

Race fuel system
Race exhaust
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race diff (standard)
Race tires 315/30R19 - 255/30R19
Wheels Compomotive ML
Forza down force front and rear


Factory Build (driver rating 1949.999 or lower)
2007 Ferrari 430 Scuderia
543hp/374tq/2977lbs S779

Race air filter
Race intake
Race fuel system
Race ignition
Race exhaust
Race valves
Race engine block
Race flywheel
Race brakes (standard)
Race suspension
Race antiroll bars
Race roll cage
Race clutch
Race trans
Race diff (standard)
Race tires 335/30R19 - 265/30R19
Lightest wheels
Forza down force front and rear

Did I say this was easy?  I meant easier I think.  Testing is now complete and for a small group of cars it was a lot harder than I expected.  It took about five days to test all 10 cars.  Total mileage was just over 3,000 miles according to odometer readings which is surprisingly comparable to the real world.

Each car went through 3 testing phases.  Phase I was a general test to get a feel for the cars and where they are at compared to each other on each track.  And also to cut out cars that don't fit in the group.  Phase II is to rebuild the cars that made it through Phase I for equality on each track.  Phase III is the fine-tune test that details the minor performance advantages and disadvantages of each car at each track and attempts to soften those differences.  It also serves as a way to discover any remaining out of balance cars that may have slipt through the cracks through the first two tests.

In total, each car was built and rebuilt 3-4 times, and 3-4 different tunes were applied to each.  That's 30-40 different builds with 30-40 different tunes for the 10 car group at 3 different tracks.  Each car has a little over 300 miles of testing as a result or about 140 laps each.  Sometimes it took the better part of an entire day just to test 2 cars.  This doesn't include a few cars that were tested and rejected earlier in the testing phase. And doesn't include a few of my helper drivers time, like Sox, Incog, and ZHP either.

I put this out there to let everyone know that these cars are not just randomly picked and slapped together. As an experienced test driver, the goal is to equalize the cars as much as possible and at a high enough level that even the fast guys have a hard time deciding which car is best. The further hope is, by doing so, everyone can have total confidence in the performance of the car of their choice.  That no matter what car you pick you can rest assured that if you have the skill your car can compete equally.  

If we simply used a P.I. hp/lbs build formula as is done in other leagues like TORA and did little to no testing, the builds would be equal but the performance of each car would be wildly unequal.  You'd have the bulk of the cars in the middle but with too many cars above the average and below the average is the problem with the formula technique.

The only track that the cars were not tested at was the 4th and final track of Season 10, COTA night.  This is because in the final as you all know by now, you are allowed to use any of the 10 cars independent of your teammate.  Even I have no idea which car might be best there.  It will be interesting to see what everyone goes with.

latte speed wrote:Don - I dont see all the builds, except for the top few cars.

You are correct.  Only 4 have been posted so far.

Got it.

Updated, and corrected, no further changes are expected.