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![030630-1 Big Block Chevy Merlin III Cast Iron Cylinder Head [345 cc Rectangular Intake Ports]](https://www.jegs.com/images/mini_750/900/955/955-030630-1.jpg)
Vehicle Info Needed030630-1 Big Block Chevy Merlin III Cast Iron Cylinder Head [345 cc Rectangular Intake Ports]
Ships on 09/15/2026
Lowest Price Guarantee- Big Block Chevy Merlin III Cast Iron Cylinder Head
- 345 cc Rectangular Intake Ports
- 119 cc Combustion Chambers
- 2.300 in. Intake Valves
- 1.880 in. Exhaust Valves
- Rectangle Port
- Assembled
- For Hydraulic Roller Camshafts
- 24-degree
- Cast iron
- 1.550 in. Valve Springs
World Product 030630-1 Big Block Chevy Merlin III Cylinder Head Features:
Emissions Note:
This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.
CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART
Improved Performance Over Chevy's Legendary LS6 Heads!
Merlin 269cc Oval Port heads are excellent for most street-driven big-blocks up to 468ci. They'll out-perform larger heads in many applications. When larger engines (454 to 540ci) require added flow, choose the Merlin Rectangle Port cylinder heads. With RightCast 320cc and 345cc intake runners, you can expect solid gains in air/fuel mixture combustion charges. These World Products heads will really respond to higher compression ratios, and are ideally suited for hot street/strip cars.
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Technical Specifications
- Material: High density cast iron
- Valve Seats: Integral intake,hardened steel exhaust
- Valve Guides: Integral cast iron
- Valve Spring Seats: Bare castings machined for 1.550'' springs
- Valve Size: 2.300'' x 1.880''
- Exhaust Flange: Port location raised .250'' , accessory bolt holes, requires ARP Head Bolts #070-135-3605.
- Included In Base Assembly: Erson stainless steel valves, ring and band style (-1 and -2 models) or PC style (-3 and -4 models) valve seals, 1.550'' (-1, -2 and -3 models) or 1.640'' (-4 models) valve springs, Erson 7° (-1 and -2 models) or 10° (-3 models) retainers and keepers.
Recommended Installation Accessories - Head Gaskets: Fel-Pro 375-1017-1 or equivalent
- Pushrods: Requires heat treated pushrods
- Rocker Arm Studs: 7/16'' with 7/16''-14 base thread
- Pushrod Guideplates: BBC Stepped 3/8''
- Spark Plugs: Accepts 14mm .460'' reach tapered seat 5/8'' hex (AC Delco R42TS/R43TS) or equivalent. Heat range may vary. Consult with engine builder.
- Intake Gasket: Fel-Pro 375-1212 or equivalent for oval port head. Fel-Pro 375-1211 or equivalent for rectangle port head.
- Exhaust Gasket: Fel-Pro 375-1410 or equivalent
- Head Bolts: 8 longer than stock required (955-832015-8)
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