New Toyota 4AGE Head

Hasselgren Engineering Develops Improved Heads for Legendary Toyota 4AGE Engine

Design image – Improved Toyota 4AGE head

BERKELEY, CA (June 17, 2020)  When Toyota introduced the 4AGE engine in 1984, few could have envisioned its decades long success in motorsports. The four-cylinder, 16-valve engine has a strong heritage, competing in the FIA World Rally championships, a number of off-road racing categories and was the chosen engine for the Toyota Atlantic open-wheel championship for 17 years. The engine is also popular in the drifting community. But, the popularity of the engine has led to a shortage of cylinder heads suitable for racing.

Hasselgren Engineering has teamed with Acrokin Engineering, Inc. to develop an improved version of this popular head. The design offers improved reliability, better performance and improved cooling attributes that are essential in motorsports. Paul Hasselgren is considered the premiere 4AGE race engine builder and plans to offer the heads as a part of a race engine package or individually. Tooling is currently in production with cylinder heads to follow.

We work with Acrokin on a daily basis, said Hasselgren. So, who better to turn to than the person responsible for the design of Toyota’s first IndyCar championship and Indianapolis 500-winning engines?

Acrokin’s CEO is Philip le Roux, who has a long history of designing racing engines with Chevrolet, Mercedes-Benz and Toyota Racing Development (TRD), designing championship and Indy 500-winning engines in the CART IndyCar series.

Paul Hasselgren has been building 4AGE’s since their introduction in Formula Atlantics, said le Roux. His deep knowledge of the engine’s strengths and weaknesses made him the ideal partner to provide real world insight for our re-creation of this popular cylinder head. We remained true to the original Toyota design, but applied modern day analysis and manufacturing methods to address issues like uneven water jacket cooling flows and port wall thicknesses.

Hasselgren Engineering Inc. is a full-service engine development firm in Berkeley, California. Services include dyno-testing, race engine building, engine machining services and parts manufacture and supply.

Acrokin Engineering Inc. is a mechanical engineering firm in Berkeley, California. They specialize in design and engineering analysis for automotive, robotics, EV, ag-tech and racing clients.

Contact Paul Hasselgren at:  510-524-2485 or at: