GT-700 build and history

The Defined Autoworks Gt-700 Rx7 is a 18 year long evolution build using "What if?" as the only goal. 

Current weight without driver- 2670 lbs
4-rotor naturally aspirated engine. Full peripheral port, drysump, race spec.
Current horsepower w/o restrictions- 661 rwhp/ 385 rwtq @9,300 rpm E85 pump gas.
Current horsepower with class restriction- 500 rwhp / 385 rwtq E85 pump gas.
335/30 front tires, 345/35 rear tires- DOT Hoosiers.
All factory unibody chassis with VIN number, street legal with license plate.
Glass windshield, factory subframes, factory suspension mounting points, factory hubs. OEM Rx7 rear differential.  


The Phoenix dream-

In 2007 just one year into starting Defined Autoworks, Logan was involved in a very serious car accident that fully destroyed his 20b powered Rx7 and burned it to the ground, leaving only the engine to remain. While in the hospital and stuck in a wheelchair for 5 months Logan dreamed of the next build to rise from the ashes. Take the naturally aspirated idea to its full extent and build a 4-rotor version. Super GT inspired wide bodywork, race transmission. Make the fastest road race car possible. That was plan. 

1st version-

  Starting with a 1993 base model rolling shell, the build kicked off in 2008. A strong foundation was needed, so it received a custom Defined Autoworks roll cage that extensively connected every load path in the chassis. All fabrication happened with Logan working on his knees while all the injuries were still healing. From there, the 3 rotor naturally aspirated/ semi peripheral port motor was removed from the previous race chassis Rx7 and installed into this one. Backed by a new T5 dogbox it made clutchless shifting effortless. Standard FEED front fenders and Pettit racing rear flares allowed 275 width front and 315 width rear racing slicks to be used. The engine was mounted far back in the chassis requiring the firewall to be modified. RG coilovers from japan was used for the suspension. Nascar monoblock brembo race calipers/rotors were custom adapted to the Rx7 spindles. AP race hang pedal assemblies were used to allow full brake bias adjustment. A 13 gallon fuel cell was installed that allowed the rear weight to be brought in closer. This configuration would receive major horsepower development into 2010 where it eventually produced 475 rear wheel horsepower. A hand machined slide throttle intake system was used to help get to this goal.  Lap times at Mid Ohio were in the 1:45 range as the car and driver (Logan Carswell) were just starting out.





























S3 magazine-
 
Editors of the Magazine "S3" contacted Logan in 2011 for a main feature content review. 

 

 
 
 
 
 
 































2nd revision-

As the 20b three rotor was very reliable and powerful, Logan had his eyes set on the next chapter and really wanted to reach for the dream that was planned out from the beginning- a 4rotor engine. So in 2011 the 4-rotor build began with the most advanced ideas ever created to mimic the legendary Mazda R26B. Full peripheral port, Ceramic apex seals, hyper light rotors 9.7:1, 5 main bearings for eccentric shaft stability, triple spark plugs just like the 787b. Slide throttle system with variable length intake. It was a huge undertaking. Backed by a nascar 4-speed race trans the powerunit was built and installed. First time on the dyno it made 610 rwhp (high reading dyno- closer to 580rwhp actual). Unfortunately, the variable length intake was plagued by friction issues at hot temps, and it was impossible to build an airbox around the unit that would fit under the hood. So, this intake was ditched in favor of a fixed unit. The length was chosen for peak midrange torque and not peak power capping out at 420rwhp but holding it across a very wide RPM band useful for racing. 
Going to the race track proving grounds Mid-Ohio, the car did a 1:38.8 on club course and hoosier DOT tires. Certainly, showing potential. 
For a full season the car was taken to the track many times and entered into NASA TT1 class racing. With the lower horsepower it fit into this class nicely. After a large GT wing was added and front splitter, the lap times dropped to 1:32.6 pro course and 1:34.5 club course at mid-ohio. This was a huge step forward for both the car and driver Logan.  Defined Autoworks documented the 4-rotor build on YouTube which would gain over 1 million views in less than a year. 





















3rd Revision-
 
The third revision really was the one that saw the original designs come full circle. Logan plotted out a very wide and aggressive body using wood stick frames covered with cardboard paper. Using these as templates they were sent out and waterjet cut in aluminum. The aluminum panels were slip rolled, bent and welded together to form the imposing body.





















Being almost 80" wide the suspension arms were custom made by Defined Auto to be 6" wider on each side. The factory subframe, and hubs were all retained. Sourcing ultra rare Volk forged magnesium mono-lug wheels was no easy task. Once purchased they were the perfect wheel to complete the vision. Custom hubs were machined to accept the mono-lug style. 









 
 




The large APR GT-1000 wing was refined, a gen 3 daytona prototype front splitter was added for much more front downforce.
 
 
 
 
 
 
 
 
 
 










With this new bodywork the transmission was definitely a weakness having only 4 gears. A SAENZ 6-speed sequential transmission was purchased and installed during the same time. Redesign of the header and collectors, power was up to 450 rwhp on the low power setting and 623 rwhp with the high power setting. Hitting the track across the following years the lap times went from 1:31 down to 1:30 pro course. 
























Gran Tourismo connection- 

Around this time SONY reached out to Logan about using his car for the sound in the new Gran Tourismo video game. They needed a soundtrack for the famous 787b but couldnt get a recording session. Going to the dyno with a massive amount of audio recording equipment, sony did a full audio profile on the Defined Autoworks Rx7. To this day, the 787b is using Defined Autoworks sound! Logan actually was inspired by the green Rx7 in Gran Tourismo for the build, so truly a proud moment. 




































That Racing Channel video-

TRC reached out on YouTube to do a full feature of the car. Equipped with straight pipe exhaust during filming, it was one of the loudest and craziest cars they ever filmed. Now reaching over 6 million views, it is also one of their most popular videos.  
























Banging gears TV show- 

In 2023 popular youtuber and pro drifter Adam LZ had made contact with Logan to have his car featured in a tv show for prime video called "Banging Gears"
In the show it was about imports vs. supercars. The show went pretty well, Logan raced against a Porsche GT3RS.
It was a long journey from ohio, as it took place in Las Vegas. Many big name people were in attendance such as Rob Dahm. 
Unfortunately, the show got cancelled after filming, and is not projected to be released. 






























Adam LZ full YouTube interview-

While at the Banging Gears TV show for filming, Adam LZ wanted to do a full video coverage of the Defined Autoworks race car. 
If you scroll to the 13 minute mark you can catch the full review.  





















"Fast Car" magazine feature-
worldwide famous magazine company "Fast Car" based in the U.K. made contact with Logan to do a full in 
depth review on the green machine 4-rotor Rx7. 

 Quad Rotor RX-7 With 700bhp: NA Four Play | Fast Car



























Refinement-

Being in a power to weight class of NASA TT1, it allowed up to 500 rwhp. Sitting at 450rwhp meant 50 horsepower was left on the table. Back to more R&D and trying E85 fuel, Logan brought power up to exactly 500rwhp for the class rules. A new dynamic intake was developed and on the high power setting produced 661 rear wheel horsepower all on SHEETZ E85 pump fuel! It was not just peak horsepower, torque was up to a staggering 385 rear wheel ft-lbs!  Bottom end torque was fully retained as well giving the engine a 3,600 wide rpm powerband.


















 






At the May 2023 NASA Mid-Ohio event,  Logan pushed his Rx7 beyond what anyone thought possible and he destroyed the TT1 club course track record posting a blistering 1:29.9 Lap. This was TWO seconds faster than the standing record. Due to time constraints the car had to enter unlimited class because of missing the TT1 legal documentation.  





 
 















Hitting Mid-Ohio again on April 2024 with class legal 500 rwhp,  the lap time dropped to a 1:27.6 on pro course. This was only 1 tenth of a second from the pro course record! Logan backed up the sizzling lap with another 1:27.8 the very next day, proving it was not a one hit wonder. 























 
 










In a full field of Porsche Gt3RS, Corvette, Z06, Viper ACR, TA2, NP01, Supra, Mustang, Camaro- the Defined Autoworks Rx7 built by Logan Carswell is typically the fastest or second fastest at the entire event. 

Current changes-

Most recently air-shift paddles have been added to the SAENZ transmission to reduce shift times.
A carbon roof replaced the OEM steel and carbon hood replaced the factory aluminum one.
A number of redundant roll cage tubes were removed yielding a 70lb loss. 
We hope to break into the 1:25's very soon at our home track Mid-Ohio. More development coming soon!