Mercury Racing 525 replacement style heads. Three intake runner sizes offer potential for increased levels of performance. We’ve retooled Dart’s PRO1 BBC castings to produce a true bolt on upgrade for the Mercury Racing 525 engine. The PRO1 24° 525 MMR is available with 310cc, 325cc or 345cc intake runners and has the correct exhaust bolt pattern for the factory manifolds. A grey chromate surface treatment inhibits salt corrosion for marine usage.

More From This Category

World Cylinder Head, Merlin, Cast Iron, Assembled, 119cc Chamber, 345cc Intake Runner, For Chevrolet, Big Block, Each

World Cylinder Head, Merlin, Cast Iron, Assembled, 119cc Chamber, 345cc Intake Runner, For Chevrolet, Big Block, Each

$2,145.71

View
Dart Cylinder Head, Assembled, Iron Eagle SS, 76cc Chamber, 165 Intake Runner, 1.94/1.5/1.25 7/161/2, Each

Dart Cylinder Head, Assembled, Iron Eagle SS, 76cc Chamber, 165 Intake Runner, 1.94/1.5/1.25 7/161/2, Each

$1,584.13

View
Dart Cylinder Head, Iron Eagle, For Ford 62cc Chamber, 215 Intake Runner, 2.05/1.60/1.550, Each

Dart Cylinder Head, Iron Eagle, For Ford 62cc Chamber, 215 Intake Runner, 2.05/1.60/1.550, Each

$1,354.21

View
Dart Cylinder Head, Bare, Engine Block, BBC 308cc 2.190x1.880, Each

Dart Cylinder Head, Bare, Engine Block, BBC 308cc 2.190x1.880, Each

$1,303.31

View
Trick Flow Top-End Combo, PowerPort®, Heads, Track Heat® Intake, Track Max® Camshaft, Big Block Mopar, For Chrysler 440, Kit

Trick Flow Top-End Combo, PowerPort®, Heads, Track Heat® Intake, Track Max® Camshaft, Big Block Mopar, For Chrysler 440, Kit

$9,782.15

View
Proflow Cylinder Head AirMax 185 & Intake Kit,  Manifold, AirMax, Dual Plane, Aluminium, Black, Square Bore, For Ford, 289/302, Each

Proflow Cylinder Head AirMax 185 & Intake Kit, Manifold, AirMax, Dual Plane, Aluminium, Black, Square Bore, For Ford, 289/302, Each

$2,756.25

View