Description: Smog Pump Relief Valve Pressure Setting Plug
Year: 1968-71
Model: Mustang, Shelby, Cougar, Ford
Model Options: All
Engine: BOSS 302, 428 CJ, 428SCJ, BOSS 429
Transmission Type: All
Factory: San Jose, Dearborn, Metuchen
Quantity: 1

Accuracy Rating: 9
Best Repro Available: YES

Jack's Comments:

This plug clicks into place setting the pressure the smog pump pressure valve releases. There are other plug colors for different engines but the blue colored plug is correct for the Boss 302, 428 S/CJ & Boss 429 smog pump relief valves. Factoid: Its common for original production plugs to fade to a opaque white with age.