Mid Dress Engine
ATK Core Return Process
JEGS and ATK appreciate your business and want to ensure that your core return is as smooth as possible.
- Core return can be any Small Block Chevy 350ci engine, except 1992-1997 LT1 style engines
- Horsepower: 330
- Torque: 380
- Block: 1987-2000 OE block 4-bolt main 1-piece seal
- Bore/Stroke: 4.040 x 3.480
- Displacement: 350
- Crankshaft: OE Reground external balance rear of crank/internal balance front of the crank
- Rods: OE powder metal 5.700 in.
- Pistons: Hypereutectic 9.1:1 compression
- Rings: Moly
- Camshaft: Hyd. flat tappet
- Cam Specs: 224/234 @ 50 .465 in/.488 ex 112 LSA
- Timing Chain: Double roller
- Cylinder Heads: ATK cast iron 76cc/165cc 1.94/1.50
- Rocker Arms: Stamped steel 1.5 ratio
- Oil Pan: Rear sump 5qt (not for Chevelles with steering behind crossmember, some Corvettes and 1962-1967 Chevy II’s)
- Oil Pump: Melling high volume
- Balancer: PowerBond internal balance 8 in. #PB1046-N
- Flexplate/Flywheel: Pioneer #FRA-159 external balance 168 tooth
- Intake Manifold: ATK dual plane intake
- Distributor: HEI (Iron gear)
- Water Pump: OE long pump
- Carburetor: Quick Fuel 680 CFM vacuum secondary’s with electric choke #HR-680
- Fuel Pump: Holley mechanical 110 GPH #12-327-11
- Spark Plugs: Champion #RV12C
- Spark Plug Wires: 8 mm
- Oil: Conventional / Non-Synthetic 10W30 with Comp Cam zinc additive #159 for first 3000 miles
- Oil Filter: Wix or K&N per application
- Timing: 34-36 Degrees
- Spark Plug Gap: .035 in.
- Firing Order: 18436572
- Octane: 91+
- Stall Converter: 2200-2500
- Exhaust: 1 5/8 in. Headers
Disclaimer: The parts listed are ATK’s recommendations of parts to be used to obtain our power figures listed. Power figures can vary based on parts used by the end-user. It is the customer’s responsibility to verify components will work in their application. Some modifications to the vehicle may be required using these and or other aftermarket parts. . ATK reserves the right to substitute parts used in engines if necessary.
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 work in a 75 Corvette?
Can you run a small shot of nitrous on this engine
Can you run a small shot of nitrous on this engine?
Can I take the TBI off the original 350 engine in my 1995 Chevy Tahoe and run it on this engine or is it carb only? Thanks in advance!
Can it run on 87 octane if needed? Non-alcohol 87 is available here too.
Let me clarify earlier question so I had a set of long headers on previous SBC looking for a good stainless steel mid set for this motor on my 1986 k10 Silverado. Thanks in advance
What type of headers do you recommend for a '86 C10 four-wheel drive application with this motor?
Given I am looking to have a carbureted motor in my 95 S-10 opting out of the computer injector system currently have a V-6 vortec engine, will this motor marry up transmission wise with this V-8? the current tranny already has shift kits and overdrive
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