Equus Mechanical Oil Pressure Gauge
Part No. 6144
Retail Price (Wal-Mart) - $7.28
We threw this wildcard in the mix just for fun. Even though the Equus 6144 is a 2" gauge, not a 2-5/8" gauge, it does come with its own face plate
and Wal-Mart retails it for a shocking $7.28. Being the last gauge in our comparison and given the fact that almost every other gauge was spot on at 40
psi, we were dying to see if this thing would measure pressure accurately... considering the price. According to the Equus website, the Equus brand targets the "value-conscious do-it-yourselfer". A bad sign. Here's what we found.

The hardware kit and instructions were complete with the added feature of an extremely cheap face plate that matched the $7.28 retail price.		Like the Summit gauge, this Equus gauge listed the grommet as optional. Since Wal-Mart is not a performance store we let the grommet omission slide.
It's true, you get what you pay for. Of the six mechanical gauges in this evaluation, the Equus was the only anomaly. It read 10 psi above all the others at idle. 50 psi.

Conclusion
In our opinion the clear winner in this simple evaluation of mechanical oil pressure gauges was the Auto Meter 3421 with the Stewart Warner 114521 coming in a close second. Auto Meter's attention to the entire installation rather than just the gauge itself supports their position in the industry. This is most clearly demonstrated by their integrated and ergonomic hardware kit. We do commend Stewart Warner for applying the same rigorous standards to their enthusiast gauges as they do to their OE gauges. Stewart Warner's "face-forward" design is also an important requirement in racing applications. Either way, both of these products are made here in the United States and that is what should be taken away from this evaluation. Spend the extra money, it's your project car for Pete's sake.