Carl Fausett

We redesigned the adapter that mounts the fuel rail gauge to the Porsche fuel rail gauge fitting, and it now has fewer parts and seals better.
The previous design used an O-ring on the metric side to seal the brass coupler. This O-ring usually worked, but not always. And the big 2 1/2" gauges were a bit bulky, I always thought.

Now our brass adapter is machined a different way, and has a flat land in the bottom of the metric side that seals up against the flat face of the fuel rail port. Seals perfectly, every time. The gauges we use now come with an 1/8" male port instead of the previous 1/4" port, and the new smaller gauge fits in the available space with fewer issues. I'm buying American-made glycerin gauges from Marshall, and have been very happy with them, as have our customers.

Reminder: this item is considered a tuning tool, and its a good one. But as such, we do not recommend you install it and leave it on there forever. Use the fuel rail gauge, set your tune, and after you confirm the tune is good and stable, please remove the gauge and place the OEM cap back on the port.

Here is the web page for those that are interested: https://928motorsports.com/parts/fuelrailgauge.php