Atomic 998 GT-A Long Motor – Ford Barra DOHC | Drag Spec | 1500hp Capable | Test Run & Blueprinted

Description:
The Atomic 998 GT-A Long Motor is the next-level evolution of our proven 698 GT-A package — engineered to handle 1500+hp with rock-solid reliability and race-proven durability. Built for serious street and drag applications, the 998 GT-A features a hand-picked 998 block, race-prepped rotating assembly, CNC-ported head, and test-run validation before it leaves our shop.

? Key Features

? Block & Machining

• Ultrasonically tested 998-series Ford block
  • Only ~1 in 10 blocks meet wall thickness & structural integrity requirements

• Fully machined and blueprint-prepped
  • Torque plate honed bores, decked to crank centerline
  • Fine Ra surface finish for MLS gasket compatibility

? Crankshaft Assembly

• Stage 3 race-prepped crankshaft
  • Crack tested, deburred, heat treated, straightened and polished
  • Pre-dowelled for billet flexplate (manual: send in your flywheel)

? Rotating Assembly

• Cosworth F1 forged pistons
  • Dish or flat top options (8.7:1 or 10.8:1 compression)
  • Coated skirts and noise-dampened crown design

• Atomic Superleggera billet rods (722g)
  • CA625 bolts, pressure-fed gudgeons, cylindrically honed tunnels

? Cylinder Head

• Atomic Stage 4 CNC-ported head
  • CNC valve job, hand-finished injector boss tracts

• Oversize stainless valves (35.5mm intake / 32.5mm exhaust)

• Race-spec ovate wire springs & heavy-duty collets

• Optional: titanium retainers, Atomic roller rockers

? Valvetrain & Timing

• Atomic billet camshafts (Stage 4+ or 5+ recommended)

• Anti-pump-up lifters with lash set for high-RPM use

• Heavy-duty timing chain kit
  • Billet crank sprocket, parabolic billet guide, uprated tensioner

? Oil System & Bottom-End Strength

• Atomic billet all-steel oil pump
  • EDM-cut gears, nitrided CRMO backing plate, upgraded spring

• Billet main caps + 10mm billet steel main girdle

• ACL Race bearings with high-flowed #6 and #7 oil paths

• ATI/Atomic SFI-approved harmonic balancer

• Optional: Big Ears high-volume baffled sump

? Assembly & Testing

• Precision blueprint assembly
  • Deck and saddle alignment, final bearing fit, crown clearance

• Fully test-run in engine cell
  • Supplied with printed test report and run-in documentation

?? What’s Included

• Fully assembled long motor

• Powder-coated rocker and timing covers (choice of colour)

• NGK spark plugs, Ford oil filter, 14L of 15W/40 run-in oil

• Spare gaskets, run-in procedure sheet, torque spec manual, Atomic merch

• 12-month conditional warranty

?? Optional Upgrades

• Fire-ring head gasket kit

• Part grout-fill of water jackets

• CNC drill block/head for 14.3mm head studs

• Atomic 14.3mm tool steel stud kit + oversized washers

• Adjustable vernier cam sprockets

• VCT delete spigots and blank-off plates

• Titanium spring retainers

• Torrington thrust bearing upgrade

• -10AN rocker cover breather fittings (welded)

Atomic 998 GT-A

The Atomic 998 is based on our reliable, proven 698 GT-A package that has been mayn customers to 1000hp. The 998 GT-A takes it another leap to push it to 1500hp with big boost. It is a rigorously engineered, high-performance long engine designed for extended high power use with reliability margin for racers who demand the ultimate in power and reliability.

Key Features:

• Optimized and strengthened block:
  • Ultrasonic tested seasoned Ford block, chosen for maximum wall thickness and strength. We estimate 1 in 10 blocks is fit for a 998
  • 698 deburring is completed before additional deburring and porting is done on oil drain back holes, webbing, and coolant passages for enhanced flow after grouting.
• Precision Crankshaft:
  • Stage 3 heat treated and race prepared crankshaft: Crack tested > deburred > heat treated > straightened > polished/chamfered polished and chamfered
  • Crank comes pre-dowelled with included billet flex plate. (Manual - send flywheel to Atomic)
• High-Performance Pistons & Rods:
  • Cosworth F1 Series dish top or flat top pistons with 8.7:1 or 10.8 compression ratio and 4-valve reliefs.
  • Atomic billet Superleggera connecting rods with CA625 bolts as standard, cylindrically ground/honed tunnels, and pressure-fed gudgeons for optimal strength and cooling. Coated side skirts and noise reducing crown to eliminate piston slap at low engine temp and RPM.
• Enhanced Cylinder Head:
  • Fully prepped Atomic Stage 4 cylinder head with CNC machined valve job, hand porting, and streamlined injector boss tracts.
  • Choice of Atomic cams (Stage 3 or 4 suggested, 4+ and 5+ possible)
  • Stainless oversize valves, Ovate Race Spec springs, and H/D collet set for superior valve control.
• Robust Valve Train & Timing:
  • Atomic anti pump-up lifters and preload settings optimized for high RPM.
  • Atomic billet camshafts (Atomic 4+ or 5+ recommended).
  • Atomic heavy-duty timing chain kit with billet steel crank sprocket and parabolic billet guide.
• Strengthened Bottom End:
  • Atomic hi-tensile 10mm billet steel main cap girdle and windage tray for increased block rigidity.
  • ACL Competition bearings with 360-degree thrust bearings as standard
  • Hi-flowed #6 and #7 main bearings.
  • Atomic/ATI Super-Damper ANDRA/SFI approved harmonic balancer and hub assembly.
• Oil System Enhancements:
  • Atomic ALL-STEEL Billet gear oil pump with EDM cut gears, billet steel end plate, and upgraded relief spring.
  • Race spec clearances throughout the engine to suit intended usage.
• Precision Machining & Assembly:
  • Fully machined block: torque plate honed cylinders, decked to crank centerline, main saddle alignment checked.
  • Fine Ra finish on deck surface and chambers relieved.
  • Precision blueprinting and assembly of long motor.
• Tested Before Delivery:
  • Engine is fully test-run in our engine test cell with comprehensive report supplied.

Included:

• New brass Welch plugs.
• Engine paint (choice of color).
• Powder coated rocker cover and timing cover (choice of hundreds of colors).
• Torque specs manual, run-in procedure sheet, spare gaskets, merch.
• 14 liters of run-in 15W/40 oil, Ford oil filter, and NGK spark plugs.
• 12-month conditional warranty.

Optional Upgrades:

• Part grout-filling of coolant passages.
• Fire ring head gasket kit.
• CNC drilled block and head to suit 14.3mm size head studs.
• Atomic M14.3mm Tool Steel Head stud kit with O/S washers.
• Adjustable vernier gear cam sprockets.
• VTC Delete spigots and Blank-off plates.
• Atomic Roller rockers.
• Titanium valve spring retainers.
• Torrington crank thrust bearing upgrade.
• High volume Big Ears sump upgrade.
• Dowelling of crank to flexplate/flywheel.
• -10 AN welded in rocker cover breathers.