US Spec Type 4 Heat Exchanger - Left - 1974-78

This standard replacement left-hand heat exchanger is designed for US specification VW Baywindow Buses manufactured from August 1974 to July 1978, fitted with Type 4 aircooled engines in 1700cc, 1800cc and 2000cc variants. On RHD vehicles, this is the passenger side heat exchanger.

The heat exchanger plays a dual role in the exhaust and heating systems. Exhaust gases pass through the internal pipes, while fresh air is directed around them inside the outer casing. As the exhaust heats the pipes, warm air is transferred into the cabin heating system, providing effective interior heating and windscreen demisting. At the same time, the exchanger forms a critical section of the exhaust system, routing gases cleanly and efficiently from the cylinder heads toward the rest of the exhaust.

US Spec Baywindow Buses use a unique heat exchanger design to suit emissions-controlled exhaust layouts, making this unit specific to USA-manufactured campers only. Over time, original heat exchangers often suffer from internal corrosion, exhaust leaks, or poor heat output due to rusted or collapsed internal pipes. Replacing a worn unit restores proper exhaust sealing, improves cabin heat, and helps maintain correct engine performance.

This reproduction heat exchanger is manufactured to replicate the original US Spec design, ensuring correct fitment, flange positioning, and heater outlet alignment. It bolts directly to the exhaust manifold, making installation straightforward without modification when used with compatible exhaust components.

Fitting & Additional Requirements

• Bolts directly to the exhaust manifold

• Gaskets and mounting hardware not included unless stated

• Designed for use with original-style US Spec exhaust systems

• Professional fitting recommended to ensure proper sealing

Quality

• Reproduction part

• Manufactured to original specification for correct fit and function

Applications

• VW Baywindow Van (US Spec): August 1974 – July 1978

  • Type 4 engines: 1700cc, 1800cc, 2000cc

  • For USA-manufactured campers only