PAIR CHEVY 350 CYLINDER HEADS STRIAGHT PLUG ASSEMBLED PROLINE HYDRAULIC ROLLER SMALL BLOCK CHEVY

DRP Small Block Chev 350 Cylinder Heads, Straight Plug Type + Assembled Pair

Hydraulic Roller Spec | DRP Valves | DRP Proline Valve Springs by PAC Racing | Straight Plug

500HP and 460 ft-lb torque from a 350ci Small Block Chev*

*Reference dyno was run with a solid flat tappet cam — indicative of the head's potential. With the right hydraulic roller cam and supporting parts, the heads will support more.

DRP 23° Chev 350 Aluminium Cylinder Heads — bolt-on horsepower for the Small Block Chevy 350

Performance cylinder heads usually come at a serious cost. DRP small block 350 chevy cylinder heads are easy on the budget without giving up casting quality, port flow efficiency, precision valve seats & machining. 

These are the as-cast version — ports and combustion chambers straight from the casting, no CNC work needed. The as-cast chambers are right out of the box, and keeping them as cast holds the chamber small and maintains compression.

Bolt on and go. All machined

What's included

Hand-assembled in Melbourne by Total Performance, spec'd for Perfromance Hydraulic roller camshaft applications:

• DRP cylinder head castings — Straight Plug, 23°, high-flow ports, Super Clean Castings
• DRP 5000 Series valves — intake and exhaust
• DRP Proline Valve Springs by PAC Racing (full spec below)
• Comp Cams hardware — Retainers, Machined Race Locks, Spring Locators.

DRP Proline Valve Springs by PAC Racing

Made in the USA by PAC Racing Springs. Small-OD LS-style dual valve springs — polished, high-RPM capable, built for aggressive hydraulic roller cams.

Spring type	Dual, small-OD LS-style, polished, Proline Series
Valve Spring Rates	160 lbs @ 1.800" & 415lbs/in
Open pressure	390 lbs @ 0.550" lift
Maximum valve lift	0.670"
Manufactured	USA — PAC Racing Springs
Designed for	Hydraulic roller camshafts - Endurance, High RPM, Aggressive cams.

Flow figures & HP potential

Valve Lift (")	Intake (CFM)	Exhaust (CFM)	HP Potential
0.200	145	106	—
0.300	192	135	—
0.400	232	160	—
0.450	242	168	503 HP
0.500	250	178	—
0.550	257	179	530 HP
0.600	261	181	537 HP
0.650	260	187	—
0.700	255	190	—

Reference dyno spec

The 500HP / 460 ft-lb result was achieved on a 350 SBC using:

• Solid flat tappet cam — 255/256 duration, 0.540"/0.534" lift, 106 LSA
• 1 ¾" headers, electric water pump
• Edelbrock Victor Jr single-plane intake (similar results expected with a dual-plane air-gap)
• 11:1 compression, domed pistons, 34° total timing

Also required to complete the build

These two parts are commonly missed — make sure you have them ordered:

• Adjustable guide plates — part # DRP-4835-GP
• Screw-in rocker studs — part # ARP 100-7101

Not sure on the combo? Call our engine builders on 1800351351 — we'll spec the cam, springs and supporting parts to match your build.

Watch the dyno runs

▶ 350 Chev Dyno — 500HP ▶ 383 Chev Dyno — 95 Octane

Lead time

Please allow 1 to 5 business days for assembly. Need them sooner? Give us a call & we can express.