Ford FE: 390 vs 428 vs 427 — What to Know Before You Build
The FE is the most misordered engine family we handle. Three reasons: people confuse FE with 385-series (429/460), they confuse 390 parts with 428 parts because "they look the same," and they treat the 427 as if it's a bigger 390. It's not. The FE is a platform family built on one bore spacing (4.630") and one bellhousing, with critical differences in block casting, main caps, oiling, head configuration, and balance.
If you're building or buying any of these three, here's what has to be on your checklist before parts go in the cart.
390 — The Volume FE
The 390 is the core that walks in the door. 4.050" bore, 3.780" stroke, 10.170" deck, 2-bolt mains. Years 1961-71 passenger car, through 1976 in F-series and E-series.
Variants matter:
- Base 390 — smaller-port heads (C5AE-E, C8AE), lower compression, mild cam. Typical rebuild core.
- 390 GT / S-code — 1966-70 Mustang GT, Fairlane GT, Comet GT. Same block, C6AE-R heads, bigger carb, hotter cam. 335 hp rated.
- 390 Police Interceptor — Galaxie / LTD fleet variant, heavier-duty rotating assembly.
- 360 truck FE — different displacement (4.050" bore × 3.500" stroke), low-flow truck heads. Don't cross-list 360 heads with 390.
Build goal for a 390: reliable street cruiser. Pair with Edelbrock Performer RPM FE heads (#60069) or a stock C6AE-R rebuild with hardened seats, Edelbrock Performer RPM dual-plane, mild hydraulic flat-tappet or retrofit roller cam, 600-650 CFM Holley. 380-425 hp pump-gas is honest.
428 — The Cobra Jet and Super Cobra Jet
The 428 is externally balanced and uses a different counterweight package than the 390. That one fact is the source of most 428 rebuild disasters. 4.130" bore, 3.984" stroke, same 10.170" deck.
Three critical 428 variants:
- 428 (base / Police Interceptor) — 1966-70 big-car cruiser, lower compression. PI bottom end is better than base but not as strong as CJ.
- 428 Cobra Jet (CJ) — April 1968-1970. Q-code Mustang, Torino, Cougar. 4.130" bore, 427 Low-Riser heads (C8OE) — the one place 428 and 427 share a head casting. Factory rated 335 hp, honestly 410+ hp.
- 428 Super Cobra Jet (SCJ) — 1969-70. CJ block + LeMans forged rods + forged crank + external oil cooler. Different balance weight than the base 428 CJ — the SCJ uses heavier counterweights on the flex-plate/damper to match the LeMans rods.
The balance rule you cannot break: a 428 CJ damper will not balance a 428 SCJ rotating assembly, and a 390 damper will NOT work on any 428. The weights are different. Every 428 build needs the damper and the flexplate/flywheel specified to match the crank and rod combination — stock 428 CJ, stock 428 SCJ, or zero-balance with an aftermarket internally-balanced stroker crank. Installing a 428 CJ flexplate on an SCJ or vice versa will vibrate a thrust bearing out in under a thousand miles.
Head note: 428 CJ uses the C8OE casting, which is the same basic casting as the 427 Low-Riser — big-valve (2.09"/1.66"), oval-port, designed for the Cobra Jet build. A rebuild kit that lists "428" without specifying CJ vs non-CJ heads is a potential mismatch. Call out chamber volume and casting number on every rebuild.
427 — Side Oiler and Top Oiler, and the Counterfeit Problem
The 427 is a factory race engine. 4.232" bore, 3.780" stroke, cross-bolted main caps on the Side Oiler, and a specialized oil gallery layout. Original NASCAR / drag / GT40 heritage. Prices reflect scarcity — a verified 427 Side Oiler block is a five-figure piece before you spend a dollar on machining.
Four common 427 variants:
- 427 Top Oiler (1963-64) — cross-bolted, but oil reaches mains last in the gallery — weakness at sustained high RPM.
- 427 Side Oiler (1965-67) — redesigned block with a dedicated gallery feeding mains first, then cam/lifters. C5AE-D / C7AE-A castings.
- Low / Medium / High Riser — refers to intake port height, not the block. Low Riser 1963-64, Medium Riser 1965-67, High Riser 1964 (drag-specific). Intakes do not interchange between riser families.
- 427 SOHC "Cammer" — museum piece, not a build platform.
Counterfeit warning: restamped 390 blocks passed off as Side Oilers is documented fraud. Verify by casting number (C5AE-D, C7AE-A), pad code, and physical inspection of the side oil gallery before accepting the block. Third-party authentication is worth the money.
Intake Manifold Compatibility Matrix
The FE intake bolts DOWN onto the heads, covering the lifter valley — the intake gasket doubles as the valley pan. Port height (riser) and port shape have to match the head exactly or the intake doesn't seal and the ports don't line up.
| Head type | Compatible intakes |
|---|---|
| Low Riser (1963-64 427, most 390 stock, 428 CJ C8OE) | Low Riser single 4V, dual 4V, 3x2 tri-power |
| Medium Riser (1965-67 427) | Medium Riser 4V, MR dual 4V — NOT Low Riser |
| High Riser (1964 427 drag) | High Riser 4V, HR dual 4V — specialized hood, NOT street |
| SCJ (1969-70 428 SCJ) | SCJ-specific intake, NOT Low Riser |
| Tunnel Port (rare 427 variant) | Tunnel Port only — completely different port geometry |
Edelbrock Performer RPM FE heads (confirm the correct part number for your bore) and Blue Thunder replicas follow the 428 CJ / Low Riser layout. CHI heads have their own intake family — CHI sells matched intakes for their 3V and High Port heads because nothing else fits.
Heads — CJ, Non-CJ, and Aftermarket
- CJ / 427 LR C8OE casting — big valve, oval port. The factory performance head. Rebuild with hardened seats for unleaded fuel, 2.09"/1.66" valves, port-match bowl work. Stock-and-port is honest on a 428 CJ or a 390 performance build.
- Non-CJ factory (C5AE-E, C8AE) — smaller port and valve. Fine for a truck 390 or a base Galaxie. Not appropriate for any serious build — the head caps the engine.
- Edelbrock Performer RPM FE — aluminum, 72cc chamber, 170cc intake runner. Bolt-on power, weight savings. Pair with Performer RPM FE intake for a matched combo.
- Blue Thunder — aluminum replicas of factory SCJ, Medium Riser, Tunnel Port. Resto-biased but strong flow for the money.
- CHI 3V / High Port / Tunnel Port — the serious-build FE head. Australian casting, CNC-ported, flows past what stock castings can touch. 450-600+ hp NA territory. Requires matched CHI intake.
The Mandatory Attach — ARP Hardened Oil Pump Driveshaft
The single FE upsell you do not skip.
The FE oil pump is driven by an intermediate shaft running from the pump up through a support into the distributor. Two failure modes kill engines:
- The stock shaft twists or spins off at the pump connection under high oil pressure with cold oil — pressure drops to zero in seconds, spins a main bearing, and the rotating assembly is done.
- The stock support bushing wears — shaft wobbles, accelerates the first failure.
Fix: ARP hardened oil pump driveshaft, FE-specific, paired with a Melling intermediate hex drive (confirm the current part number) or a Precision Oil Pumps pinned-driveshaft conversion for serious builds. Every FE rebuild kit on the invoice needs a matching ARP shaft. Non-negotiable.
Which Engine for Which Build
- Street cruiser, 400 hp, pump gas, tow occasionally — 390 with Edelbrock Performer RPM FE heads and a hydraulic roller. Cheapest path, honest performance, parts availability.
- Resto Mustang 428 CJ / Torino CJ / Shelby GT500 — genuine 428 CJ short block with LeMans rods (or SCJ if genuine), C8OE heads, period-correct iron intake OR Edelbrock Performer RPM FE for more power. External balance everything.
- 427 Side Oiler resto or road race — verified SO block only, cross-bolt ARP 2000 kit, period-correct or CHI heads depending on build intent, Medium Riser intake. Budget the build at resto-market numbers; this is not a volume play.
What to Do Next
- Verify the block — casting number, pad code, main cap style — before ordering parts
- Match damper and flexplate to the rotating assembly, not the block
- Check intake riser family against the heads at the SKU filter before ordering the intake
- Add the ARP hardened oil pump driveshaft to every FE rebuild — zero exceptions