Items You Need
ATK Core Return Process
JEGS and ATK appreciate your business and want to ensure that your core return is as smooth as possible.
Please CLICK HERE for ATK Core Return Process
- Core return can be any Small Block Chevy 350ci engine, except 1992-1997 LT1 style engines
This engine is an upgrade for 1996-2000 Chevy trucks with a Vortec 350. The ECM must be tuned and headers are needed to get the potential out of this engine.
- Horsepower: 315 hp
- Torque: 400 lb/ft
- Seasoned OE 4 bolt main 1pc seal 1996-2000
- Bore/Stroke: 4.040" x 3.480"
- Displacement: 350ci
- Crankshaft: OE Reground 1 piece seal crank
- Balance: External rear, internal front
- Rods: OE powder metal 5.7"
- Compression Ratio: 9.3:1
- Pistons: Hypereutectic
- Rings: Moly
- Camshaft: Hydraulic roller
- Cam Duration @ .050": Intake 198 / Exhaust 210
- Cam Lift: Intake .435" / Exhaust .462"
- Lobe Separation Angle: 114lsa
- Timing Chain: Single roller
Cylinder Head Information:
- Cylinder Heads: Vortec cast iron
- Combustion Chamber: 64cc
- Valve Size: 1.94" Intake / 1.50" Exhaust
- Rocker Arms: Stamped steel 1.5
Oil Pan Information:
- Oil Pan: Rear sump 5qt (not for Chevelles with steering behind crossmember, some Corvettes, and 1962-1967 Chevy II's
- Oil Pump: Melling standard volume
- Short Block
- Timing Set
- Cylinder Heads
- Valve Covers
- Timing Cover
- Oil Pan
- Oil Pump & Pickup Tube
- Exhaust: 1-5/8" Headers
- Firing Order: 18436572
- Octane: 91+
- Oil: 10W30 (Conventional / Non Synthetic)
- Oil Filter: Wix or K&N
- Spark Plug Gap: .035"
- Stall Converter: Stock
- Timing: 34-36 Degrees
- Tuning: ECM MUST BE TUNED TO RUN PROPERLY. WITHOUT DOING SO THE ENGINE CAN BE DAMAGED
- Balancer: Internal balance 8"
- Distributor: Stock (iron gear)
- Flexplate/Flywheel: External balance 168 tooth 1987-Up
- Intake Manifold: Edelbrock Performer RPM #350-7116
- Fuel Pump: Stock
- Spark Plugs: Autotile #417-605
- Spark Plug Wires: Stock
- Water Pump: Stock
Disclaimer: The parts listed are ATK's recommendations of parts to be used to obtain the power figures listed. Power figures can vary based on parts used by the end user. Some modifications to the vehicle may be required using these and or other aftermarket parts.
Engine Break-In Procedure
Use or break-in oil or conventional (non-synthetic) 10w30 oil with zinc additive for the first 500 miles of operation. Do not drive for long periods at any single speed, always vary your speed. Do not tow a trailer or put other heavy loads on the vehicle. It is best to avoid long periods of idling during this period. Check the engine oil and coolant levels daily.
Engines with flat tappet hydraulic cams only - Run the engine between 2,000 and 2,500 RPM's, with no-load on the engine for the first 30 minutes. Let the engine cool down completely and repeat process 2-3 more times. Do not idle the engine for any extended period at this time, this is critical to break in the camshaft.
At 500 Miles change the engine oil and filter using conventional (non-synthetic) oil with a zinc additive. Check fuel and ignition settings, adjust valves (where applicable). Drive the next 500 miles normally, without high RPM's (below 5000 RPM), hard use, or extended periods of high loading or long periods of idling.
Change the oil and oil filter again at 1,000 miles. Continue using conventional (non-synthetic) oils and zinc additive, until about 4,000 miles. At that point, you may run a quality 10w30 synthetic oil if you choose. Use of oil with zinc or a zinc additive for the life of your engine is recommended.
Will this engine fit in place of a 454 in a 1997 Chevy Silverado K3500 dually crew cab?? If not please recommend what engines will that are available? I’m waiting on the 454 but ready to put a 350 or anything that fits in stock??
what headers would be the best fit for my 96 k2500
What should be used to tune the ECM?
I have a 2000 Chevy K2500 4wd. Will this be a good replacement for my stock 350? It is now tired with 200k miles?
I have a 88 Suburban and am looking to do a motor swap and run a Holly Stealth TBI. Is this even an option with this motor? Thanks for your help.
1999 Chevy Tahoe LT 4x4 350- You all stated I need headers, do you offer any headers that will fit my application ?
Hello would this engine fit in a 1994 K1500 Silverado 5.7 L and what would I need to do that ? Please
I have a 1996 Chevy Silverado I have the stock 5.7 still can I use some parts off of the stock motor and put them on this one
WARNING: Motor vehicles contain fuel, oils and fluids, battery posts, terminals and related accessories which contain lead and lead compounds and other chemicals known to the State of California to cause cancer, birth defects and other reproductive harm. These chemicals are found in vehicles, vehicle parts and accessories, both new and as replacements. When being serviced, these vehicles generate used oil, waste fluids, grease, fumes and particulates, all known to the State of California to cause cancer, birth defects, and reproductive harm.
WARNING: Some dust created by power sanding, sawing, grinding, drilling, and other construction activities contains chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Some examples of these chemicals are: lead from lead-based paints, crystalline silica from bricks and cement and other masonry products, and arsenic and chromium from chemically treated lumber. Your risk from exposure to these chemicals varies, depending on how often you do this type of work. To reduce your exposure, work in a well-ventilated area and with approved safety equipment, such as dust masks that are specially designed to filter out microscopic particles.
WARNING: The wires of these products contain chemicals known to the State of California to cause cancer and birth defects or other reproductive harm. Wash hands after handling.