





Mantis-Manometer | M88 + S38 6 Port Air Bypass Adjustment Tool
Angry Ass has partnered with Mantis-Manometer to offer this critical maintenance tool. This six port manometer is used to finely tune the idle and off idle performance of the BMW M88 + S38B35, B36 + B38. The item comes fully assembled with 10 feet of vacuum tubing, high temperature silicone ends, factory calibrated to 8.5inHg, vacuum tested, and filled with oil. It solves the poor factory tuning process by sampling all six ports at the same time. With the provided detailed laminated instructions an enthusiast can quickly set the bypass ports to the factory specification and enjoy a smooth running engine.
Angry Ass has partnered with Mantis-Manometer to offer this critical maintenance tool. This six port manometer is used to finely tune the idle and off idle performance of the BMW M88 + S38B35, B36 + B38. The item comes fully assembled with 10 feet of vacuum tubing, high temperature silicone ends, factory calibrated to 8.5inHg, vacuum tested, and filled with oil. It solves the poor factory tuning process by sampling all six ports at the same time. With the provided detailed laminated instructions an enthusiast can quickly set the bypass ports to the factory specification and enjoy a smooth running engine.
Angry Ass has partnered with Mantis-Manometer to offer this critical maintenance tool. This six port manometer is used to finely tune the idle and off idle performance of the BMW M88 + S38B35, B36 + B38. The item comes fully assembled with 10 feet of vacuum tubing, high temperature silicone ends, factory calibrated to 8.5inHg, vacuum tested, and filled with oil. It solves the poor factory tuning process by sampling all six ports at the same time. With the provided detailed laminated instructions an enthusiast can quickly set the bypass ports to the factory specification and enjoy a smooth running engine.
Additional Information
Compatible with the following engines:
M88B35
S38B35
S38B36
S38B38
The BMW factory process relies on separately testing each of the six ITB bypass ports and calculating average port vacuum. This process introduces errors as the idle speed fluctuates during testing and results in a rough off idle condition and poor drive-ability below 2,000 RPM.
The Mantis-Manometer was enthusiast developed and tested across a broad range of S38s over multiple years.
Pair with our Angry Ass | S38 + M88/3 Throttle Adjustment Dial Indicator Mount(s) to help keep your S38 running smoothly.