Small Block Engine Intake Manifolds & Components

• Aluminum manifold used on all 350 HO engines
• Can be used on all Small-Blocks through 1986
• Dual-pattern carburetor flange is approximately 1/2" lower than the 1970 LT1 intake, yet produces the same horsepower

• Provisions for all late-model accessory brackets, EGR, and an integral hot-air choke
• A heat shield can be mounted underneath for improved performance

NOTE: Open carburetor spacer is not recommended for use with dual-plane intake manifolds.

• Designed for 283-400-cubic-inch engines using Vortec cylinder heads P/N 12558060, P/N 19300956, P/N 19300955, P/N 19331470, or P/N 19331472
• Has 4-bolts per side to attach it to these cylinder heads
• Aluminum high-rise design maximizes horsepower and delivers a broad torque curve

• Accepts a square-bore 4150-style carburetor and includes externally plumbed hot water crossover passage
• Use manifold gasket P/N 89017465 and eight attachment bolts, P/N 12550027

NOTE: Vortec heads were originally released on 1996-1999 truck engines. Check for hood clearance, especially with Corvette.

NOTE: Open carburetor spacer is not recommended for use with dual-plane intake manifolds.

• This dual-bolt-pattern aluminum manifold will work with all Vortec cylinder heads P/N 12529093, P/N 12558060, P/N 19300956, P/N 19300995, P/N 19331470, or P/N 19331472
• Will accept Holley or Quadrajet-style carburetors
• Will accept an EGR valve, P/N 17052693

• To block EGR port, use P/N 12556596
• Requires intake manifold gasket kit P/N 19301685 and 8 special manifold bolts, P/N 12550027

NOTE: Open carburetor spacer is not recommended for use with dual-plane intake manifolds.

• Designed for throttle-body fuel injection
• Aluminum intake will work with all Vortec cylinder heads, including P/N 12558060, P/N 19300956, P/N 19300955, P/N 19331470, or P/N 19331472

• Also accepts EGR  

NOTE: The exhaust manifold from 1996-and-newer pickup trucks with RPO L31 350 engine, P/N 12557828, is drilled and tapped to accept an EGR tube. EGR pipe P/N 10220275 can be used with EGR Valve P/N 19210662 and gasket P/N 12337972. This manifold is primarily intended for use with Vortec heads on pre-1996 engine blocks. Blocks manufactured in 1995 or earlier have thermostat bypass passage from the block directly to the water pump. If manifold is used on 1996 and later engines (which do not have the bypass in the block), you must run a coolant bypass line from the manifold to the 5/8" hose nipple on the water pump (passenger’s side). Suggested routing is from the 3/8 NPSF boss on manifold to the water pump.

• Designed to deliver the most power and torque with Vortec cylinder head P/N 12529093, P/N 12558060, P/N 19300956, P/N 19300955, P/N 19331470 or P/N 19331472

• Use intake manifold gasket kit P/N 19301685 and 8 special manifold bolts P/N 12550027

• Fits 1992-1996 Gen II LT1 engines and permits the use of a carburetor
• Long runners increase engine torque up to 30 lb.-ft. without sacrificing top-end horsepower

• There are no water coolant holes on this manifold

• Original Equipment on SP 350/357 Engine
• Dual-Plane Design for Maximum torque
• Designed for 4150-style 4 bbl carb

• Fits late-model Vortec style heads
• Do not use a carb spacer with this manifold

NOTE: Open carburetor spacer is not recommended for use with dual-plane intake manifolds.

• Runners of this single-plane aluminum intake manifold are raised .200" to match the ports of Bowtie cylinder head P/N 10051101 (discontinued)
• Air gap beneath the runners isolates the intake charge from hot engine oil
• A 2" carburetor spacer is recommended

• Accepts standard-flange 4-bbl carb
• For competition use only, as there are no heat riser passages   

NOTE: Open carburetor spacer is not recommended for use with dual-plane intake manifolds.

• This standard-runner manifold is based on the raised-runner intake P/N 10051103 (see above)

• Retro-fit fuel injection kit will fit V-8 engines using Vortec cylinder heads P/N 12558060, P/N 19300956, P/N 19300955, P/N 19331470, or P/N 19331472
• Must be used with an aftermarket ECU and wiring harness with the proper calibration

• The same as used on Ram Jet 350 engine P/N 12499120. (MEFI with ECU and Wire Harness Kit P/N 12499116 is not calibrated for anything other than Ram Jet 350.)
  

• Used on the Ram Jet 350 engine assembly P/N 12499120
• Bare manifold only – no throttle body, injector rails, injectors, bracket or other components

• See P/N 12498032 for complete manifold kit

• Replacement ECU for all Ram Jet 350 crate engines, MEFI 3 P/N 12495515 or MEFI 4 P/N 12499120 MEFI 4 Ram Jet engine is a closed-loop system that gives a much smoother idle and improved performance 
  

NOTE: Replacing the ECU on MEFI 3 Ram Jet engine P/N 12495515 requires using new wire harness kit P/N 12499116, or use jumper wire P/N 88963118 to use MEFI 4 ECU as an open-loop system.  

• Use to convert a Ram Jet 350 from MEFI 3 to the newer MEFI 4 design, which provides a better idle through closed-loop operation

• Includes ECU module P/N 88962717, wire harness P/N 88961967, oxygen sensor P/N 19178918, intake air temp sensor P/N 25036751, and oxygen sensor fitting P/N 15156588  

NOTE: ECU is programmed with a “green mode” that controls the rpm for the break-in period. During this period, engine speed is limited to 4,000 rpm in the first hour, 4,500 rpm in the second hour and 5,500 rpm in the third hour.

• Designed to be used with the MEFI 4 Ram Jet 350 P/N 12499120 and MEFI 4 ECU P/N 88962717  

• Used on all MEFI 4 electronic controlled ignition systems

• Should be welded into the exhaust pipe so the oxygen sensor can be screwed into the exhaust system  

• Designed for use with the MEFI 3 350 Ram Jet engine P/N 12495515 using ECU P/N 12489488  

• Developed for stock car short tracks and works well on road racing engines
• Features runners and plenum volume sized to enhance mid-range torque. Aluminum intake fits 18° heads casting
• Manifold is ideal for 310-cubic-inch road racing and 358-cubic-inch short track engines
• Manifold flanges are 0.590" thick to promote a good gasket seal

• An auxiliary water line boss at the rear of the casting improves water flow
• Weight 22.5 lbs
• Volume 2700cc

• A 2-piece “dry” aluminum manifold “spider” consisting of the runners and plenum only

• The runners, called the “spider assembly” by racers, along with valley plate assembly – the common term for the bottom section of the intake (see P/N 24502654 below) – are designed for use with the 18° cylinder heads with a date code of June 1996 or newer

• Universal aluminum valley plate is designed for use with 18°cylinder heads
• Can be used with dedicated 2-piece manifold spiders, existing 1-piece intake manifolds which have been properly machined for use as a dry manifold, or fabricated manifold designs

• Valley plate has cast-in integral passages to equalize coolant flow from the front and the rear of the cylinder heads
• Fits heads dated June 1996 and later  

NOTE: Important information about gasket matching: Gasket flanges are machined to provide the proper port alignment with standard runner locations. Runners in heads and manifold must be matched by engine builder. Often, the gasket will line up with the top of the port so removal is required at the bottom of the port. Gaskets that can be used with this manifold are: Fel-Pro® P/N 1205 and P/N 1206, and Mr. Gasket® P/N 102. Always match the gasket to the cylinder head you plan to use to ensure a correct fit.

• Aluminum manifold has more material in the runners and plenum to accept more flexibility in porting

• Designed for Stock Car Racing restrictor-plate racing and is used with valley plate assembly P/N 12370840 (see below)

• Designed for Stock Car-style racing and high-rpm engines
• Additional aluminum in the runners and plenum allows more flexibility in porting

• Must be used with valley plate assembly P/N 12370840 or P/N 88958659

• Aluminum valley cover is used with manifold runners P/N 12480096 and P/N 88958617 on SB2.2 cylinder heads for Stock Car Racing
  

• Aluminum valley cover is used with manifold runners P/N 12480096, P/N 88958617 and P/N 88958691
• Does not incorporate an inspection cover, but has revised integral water passage for improved coolant flow from the front and rear of the cylinder heads

• Uses AN -24 fitting for water outlet; can use reducer for AN-20 fitting

• Fits R0X manifold and R0X head P/N 88958667
  

• Covers the choke hole on the 350 HO manifold P/N 10185063

• Use gasket P/N 14096848 and screw P/N 9442184 with washer P/N 9439511

• Covers the EGR valve port on the 350 HO manifold P/N 10185063

• Use gasket P/N 12554530 and screw P/N 9442184 with washer P/N 9439511

• 7/8"-15 plug is used to seal off EGR pipe holes on intake manifold P/N 12496820 and P/N 12496821

• Chrome water neck with neoprene O-ring and chrome bolts

• For 1966-1975 full-size Chevrolet, Camaro, and Chevelle V-8 engines

• Natural finish
  

• For 302-350 high-performance Small-Blocks built from 1971-1986, and all ZZ350 high-performance engines
• Gaskets fit standard intake port location

• Do not use with raised runner cylinder heads
• Includes 2 gaskets

• Designed for Vortec heads, P/N 12558060, P/N 19300955 and P/N 19300956 only
• Gasket thickness is 0.120" (1/8"), post size is 1.080" x 2.160" with tapered wall, Print-O-Seal design

• Has both early style 6-bolt pattern and Vortec 4-bolt pattern
• Includes 2 gaskets
   

• Production gasket for all Vortec-design cylinder heads (4-bolt attachment to cylinder heads P/N 12529093 and P/N 12558060)
• Requires the use of GM attachment bolt P/N 12550027, because the bolt has a ball design on the end that sits in the head so it will not crush the intake manifold gasket

• Includes 2 gaskets

• Used on the LT4 engine P/N 12371172
• Can be used with all LT4 heads and is designed not to cover part of the cylinder head opening – as production gaskets do

• Includes 2 gaskets

• Used only on the splayed-valve V-8 cylinder heads P/N 24502517
• Includes 2 gaskets
  

• Includes 2 gaskets
  

• Used only with V-8 18° high port cylinder heads P/N 10134363 and P/N 24502580

• Includes 2 gaskets