Sniper X 24° CNC Ported
355cc BBC Cylinder Heads
Series P/N: 174-X-C35-03-X
- 100% CNC Ported for Mega Flow
- 24 Degree OEM X275 Class Accepted Valve Angle
- 119cc Heart Shaped Combustion Chamber
- 2.300 Intake & 1.850 Exhaust Valves
- Works with Standard BBC Pistons
- 5/16" or 11/32" Valve Stem Dia Available
The Sniper X cylinder head is the latest BBC head offered in the Sniper Series. Designed with the most up to date technology available, this Sniper X head flows over 430cfm on a 355cc runner and over 325cfm on the exhaust! We started with the most sound casting available and then spent months developing the best port and chamber for a 24° head.
All heads are 100% CNC ported including the chamber and features a 5 angle valve job with .350" longer intake valves and .100" longer exhaust valves. The Sniper X uses standard BBC parts including available Jesel and T&D shaft rockers or you can use standard stud mounted rockers. As an added bonus, the Sniper X maintains standard BBC valve centerlines so it works with regular BBC pistons.
When your ready to put your 565 cid or larger BBC up against the world, the Sniper X head is for you.
Details
Series P/N: 174X 355cc BBC Sniper X Head Specifications
| Material: | Aerospace Specification, A356 Aluminum Alloy (Primary Virgin Ingot) |
| Valve Angle: | 24° valve angle to provide you with bolt on compatibility |
| Intake Port Volume & Shape: | Rectangle-Shaped, Fully CNC Machined 355cc |
| Intake Port Flow: | 355cc = 430cfm @.800 lift |
| Exhaust Port Shape: | Round, Raised Port, Fully CNC Machined |
| Combustion Chamber: | CNC - 119cc (Milled 105cc) New design to promote wet-flow and efficiency! |
| Milling: | Angle - .0070" per cc Flat - .0050" per cc |
| Valve Spring Pocket: | Maximum of 1.625" (no deeper) |
| Bore Spacing: | Standard BBC 4.840" |
| Intake Manifold | All conventional manifolds will bolt right up (Some port matching may be required) |
| Pistons | Standard BBC Pistons |
| Head Bolts/Studs | Requires 1" longer than stock head/bolt or stud next to exhaust ports |
| Valve Diameter | Intake - 2.300", Exhaust - 1.850" |
| Valve Stem | 5/16" (PN 174-X-C35-03-5) or 11/32" (PN 174-X-C35-03) |
| Valve Length: | Intake 5.525" (2.100" Install), Exhaust 5.540" (2.100"Install) |
| Deck Thickness: | 1/2" |
| Valve Guides: | Manganese Bronze to assist in extending valve life .502" OD |
| Valve Seat: | 50° - Ductile Iron Material |
| Valve Train: | Uses Stock or Most Aftermarket Rocker Systems (T&D P/N 3211-170/170) |
| Spark Plugs: | Revised location to improve flame travel. Machined for a gasketed 3/4" reach plug NGK R5671A-7 or colder |
| Head Bolts: | Requires 1" longer head bolt next to exhaust ports |
| Accessories: | Heads drilled and taped for standard accessories (alternator mount holes) |
| Engine Size: | 355cc - 502cid + /8500 rpm |
| Application: | High Performance (i.e. strip / marine) |
174X Parts and Accessories
| Intake Manifold: | Pro-Filer Sniper Jr. Single Plane, Sniper Single Plane or Sniper Tunnel Ram |
| Intake Gasket: | Call |
| Valve Cover Gasket: | Stock BBC Fel-Pro 1635 |
| Exhaust Gasket: | Std BBC (match to header size) |
| 4.375 Bore Head Gaskets: | Cometic C5329-XXX (xxx = thickness) |
| 4.54 Bore Head Gaskets: | Cometic C5330-XXX (xxx = thickness) or Fel-Pro 1017 |
| 4.63 Bore Head Gaskets: | Cometic C5331-XXX (xxx = thickness) or Fel-Pro 1057 |
| Valve Covers: | Standard BBC Bolt Pattern Pro-Filer PN 191 |
| Rockers: | Standard BBC or shaft rockers (T & D and Jesel both have kits) |
| Pistons: | Most 24 Degree Aftermarket |
| Valve Springs: | Up to 1.625" Dia |
| Valve Spring Installed Height: | 2.100" |
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