
- Description
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
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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
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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
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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
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Atomic Stage 4 CNC-ported head
• CNC valve job, hand-finished injector boss tracts -
Oversize stainless valves (35.5mm intake / 32.5mm exhaust)
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Race-spec ovate wire springs & heavy-duty collets
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Optional: titanium retainers, Atomic roller rockers
✅ Valvetrain & Timing
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Atomic billet camshafts (Stage 4+ or 5+ recommended)
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Anti-pump-up lifters with lash set for high-RPM use
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Heavy-duty timing chain kit
• Billet crank sprocket, parabolic billet guide, uprated tensioner
✅ Oil System & Bottom-End Strength
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Atomic billet all-steel oil pump
• EDM-cut gears, nitrided CRMO backing plate, upgraded spring -
Billet main caps + 10mm billet steel main girdle
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ACL Race bearings with high-flowed #6 and #7 oil paths
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ATI/Atomic SFI-approved harmonic balancer
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Optional: Big Ears high-volume baffled sump
✅ Assembly & Testing
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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
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Fully assembled long motor
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Powder-coated rocker and timing covers (choice of colour)
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NGK spark plugs, Ford oil filter, 14L of 15W/40 run-in oil
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Spare gaskets, run-in procedure sheet, torque spec manual, Atomic merch
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12-month conditional warranty
🔧 Optional Upgrades
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Fire-ring head gasket kit
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Part grout-fill of water jackets
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CNC drill block/head for 14.3mm head studs
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Atomic 14.3mm tool steel stud kit + oversized washers
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Adjustable vernier cam sprockets
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VCT delete spigots and blank-off plates
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Titanium spring retainers
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Torrington thrust bearing upgrade
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-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:
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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.
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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)
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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.
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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.
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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.
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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.
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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.
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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.
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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.