Newly-upgraded Cayman GT4 and more power delivered from a 4.5-liter engine!!!

Autowerks is a leading performance tuning shop based in Bangkok, Thailand specializing in hi-end European tuning, Founded by 2 brothers Andrew & Warren Adulayavichitr who both share a great passion for the ultimate driving experience and going fast! Both of them have a passionate interest in sports cars and supercars, many of which have been tuned and modified by their workshop. Additionally, these two car enthusiasts have vast experience in performance upgrades for a huge number of Porsches, all of which can be compiled on their long, full list of completed projects.

The Autowerks team makes every attempt to best upgrade performance of every single part of vehicles including engine modifications, ECU tuning, suspension and handling upgrades as well aero kit packages. Today Autowerks is sharing with us there latest Cayman GT4.5 conversions!

As many of you may have seen the recent social media hype about the ultimate street Cayman GT4 from DeMan Motorsport in the USA, which has turned Porsche enthusiasts heads around the world.

DeMan Motorsport is a full service Porsche facility located in New York. Rick DeMan, the founder of DeMan Motorsport, has gained over 30 years of experience in racing and won numerous and races & championships in the USA Porsche racing scene. He started making a name for himself by racing the 914s from the late 1990s until the early 2000s. The DeMan team specializes in custom engineered championship winning cars as well as routine service work including engine and transmission rebuilds.

The initiation of the 4.5-liter engine upgrade package started with DeMan’s great passion for motorsports. He started out tinkering with his personal GT4 by increasing the engine’s capacity from 3.8 to 4.0 liters and then to 4.25 liters and eventually the 4.5 liter 560hp naturally aspirated flatsix was born! In 2019 Autowerks partnered with DeMan motorsport to bring the renowned 4.5L to Asia!

Since then, Autowerks has converted the largest number of the 4.5-liter GT4 Porsche’s outside of the USA and Thailand is the 1st country in Asia to have over 5 examples with a few more on the way.

With great knowledge of the 981 Platform, the team at Autowerks can complete the transformation of the GT4 to 4.5L within a short period of time. The transformation includes a complete engine change accompanied with a close-ratio gearbox. With its foresight to meet customer satisfaction and drivability and experience with the GT4 platform, Autowerks has additionally improved the cooling systems with CSF upgraded radiators, Manthey-Racing brake pads and braided brake lines for the factory PCCB Brake system and Akrapovič’s exhaust system all at once.

Autowerks indeed, has released several upgraded 4.5-liter GT4 Porsches. Like these two cars, the beautiful GT Silver GT4 and the “Pink Pig” inspired GT4. The DeMan close-ratio gearbox coupled with the 4.5 offers a extremely visceral driving experience with the extraordinary power output of its engine and torque is further proved through a dynamometer, or ‘dyno’ test.

It is apparent from the graph that both power and torque lines dramatically climb up, even at low revs. Power, in the meantime, is constantly produced and this is such a precise replacement of a typical 3.8-liter engine’s weakness in low torque delivery adding over 100NM of torques throughout the rev limit and a whopping 150+Hp over the factory 3.8 output!


It can be concluded that the 4.5-liter engine upgrade perfectly fits the GT4 981. Firstly, as the GT4 model is originally housed with a 3.8-liter 6-cylinder engine from the 911 Carrera S model along with a manual transmission, bolt-on modifications can be effortlessly added to the car. Besides, the upgrades and modifications are properly aligned with the front suspension derived from the GT3 model, enhancing the performance of this mid range model. Considering value for money, the cost of the upgrade package truly makes sense, and you can now afford a used Porsche GT4 that packs a bigger punch than any cur- rent GT3RS Model.