400 Horsepower 318 BuildsBelow are the specifications for the infamous "400 HP 318" articles that are often referred to on many Mopar forums.
"A Parts Book 400 HP 318" - Mopar Muscle - September 2004This particular combo from an article in Mopar Muscle Magazine made 400 hp at 6,150 RPM and 382 lb/ft peak torque at 4,900 RPM:
- Block: 1968 Plymouth Barracuda 318 block - zero decked (pistons flush with the block at TDC), line honed
- Crank: Forged 273 crank
- Rods: 73-and-up LA connecting rods with ARP rod-bolts.
- Pistons: Keith Black KB 167 hypereutectic
- Rings: Federal Mogul pre-gapped moly rings
- Windage tray: Factory 318 police car windage tray
- Heads: Magnum heads (59 cc closed chambers, 1.92" intake/1.625" exhaust, 1.6:1 rocker ratio)
- Head gaskets: .040" head gaskets
- Compression: 10:1 compression with Magnum heads, zero-deck short-block and .040" head gaskets.
- Cam: Comp Cams 280H Magnum camshaft, single-pattern, 280* adv. duration, 230* duration @ .050", .512" lift with the 1.6:1 Magnum heads (normally .480" lift with 1.5:1 LA heads).
- Pushrods: Comp Cams #7960 pushrods (7.650"
- Intake: Mopar Performance M1 single-plane for Magnum heads
- Exhaust: TTI 1 5/8" to 1 3/4" step headers
- Ignition: MSD distributor, box and wires
- Carburetor: Mighty Demon 750 CFM
- Carburetor Spacer: Wilson 1-inch tapered spacer
- Engine oil: Royal Purple 10w-30
"Junkyard Jewel: 400 HP 318" - Hot Rod - April 2003This particular combo from a Hot Rod Magazine article made 406 hp at 5,900 RPM and 408 lb/ft peak torque at 4,700 RPM. This engine already had over 220,000 miles on it when the test was done. New rings and bearings were done at 120,000 miles.
- Block: 1984 Dodge Diplomat police car 318 short block with around 220,000 miles. Pistons were 0.058" below deck.
- Crank: Factory stock 318 crank
- Rods: Factory stock 318 connecting rods.
- Pistons: Factory stock 318 police hypereutectic pistons
- Rings: Unknown brand moly rings - redone at 100,000 miles
- Windage tray: Factory 318 police car windage tray
- Heads: 4323302 castings, usually found on 1985 to 1991 318 2-barrel Fifth Avenues, Diplomats, Gran Furys, and Dodge pickups and vans. Stock chamber volume is 59 cc. The following head work was done:
- Milled 0.050" reducing chamber volume to 52cc and raising the compression ratio to just under 10.0:1.
- Machined to add 2.02/1.60 Milodon street valves
- Fully ported, including gasket matching intake port runners to 360 size, and gasket matching exhaust runners to Fel-Pro header gasket size
- Head gaskets: Mopar Performance P4349557 thin head gaskets
- Compression: Slightly under 10:1 compression with milled 302 heads, factory pistons and Mopar Performance P4349557 head gaskets.
- Cam: Comp Cams Xtreme Energy 268 camshaft, 224*/230* .050", 110-degree LSA, .477"/.480" lift
- Pushrods: Unknown
- Intake: Edelbrock 7576 Performer RPM AirGap
- Exhaust: Hooker 5901 1 5/8" 4 into 1 headers
- Ignition: Mopar factory spec electronic ignition
- Carburetor: Holley 650 double-pumper core, ProForm 67100C main body
- Carburetor Spacer: PAW TDP-2084 1-inch open spacer
- Engine oil: Unknown
Related Topic:Notes:- Despite all of the modifications to these engines, the torque figures for both builds were lower than that of a basically stock Dodge Magnum 5.9 (360) engine baseline dyno test done for a Mopar Muscle article (Magnum Muscle: Serious Bolt-On Power For Magnum Mills). The camshaft was the stock factory 5.9 cam used in Dodge trucks. The only modifications to the 5.9 were bolt-ons; a Mopar M1 single plane intake, a Barry Grant Mighty Demon 750 CFM carburetor and TTI headers. The 5.9 produced 345 HP at 4,600 RPM and 426 lb/ft of torque at 3,800 RPM - an average of 1,000 RPM lower than both 318 builds.
Sources:
Author
Topic: Engines: 400 Horsepower 318 Builds (Read 56588 times)
Your Privacy Choices