SOLD Butler Crate Engine 400 Block 467 cu. in. Turn Key EFI

560 horsepower, 589 lb-ft — pump gas, naturally aspirated

A Butler Performance in-house build: 467 cubic inches with CNC-ported round port heads, self-tuning Holley EFI and Doug's round port headers. Assembled and blueprinted here in Lawrenceburg, run and tuned on our own engine dyno, and the numbers below are what it actually made — corrected, in our cell, on the day.

Why that plateau matters

Peak horsepower is a single instant. What you feel through a gear is the area under the curve. An engine that holds 558–560 HP across 700 rpm keeps pulling through the top of every gear instead of signing off the moment it reaches its headline number.

Underneath it, torque is over 500 lb-ft from 3,500 to 5,800 rpm and peaks at 589 at 4600. Broad underneath, flat on top — that is a street engine that behaves like a much bigger one.

Round port heads and matched induction

The heads are Butler 87cc Edelbrock round port castings, CNC ported to 325+ CFM, supplied complete. Round port flows more than a D-port, and it is the reason the power curve stays flat past 5,000 rpm rather than falling over.

The Edelbrock Torker II intake is port matched to those specific heads rather than bolted on out of the box, and the engine breathes out through Doug's 1 7/8" round port headers with 3 1/2" collectors — sized for the port, not for whatever was on the shelf. Matching the induction to the head is the difference between a set of good castings and a good engine.

Built to be leaned on

The 400 block was converted to four-bolt mains with Butler steel caps and ARP studs, rebored with a torque plate, square decked, align bored across three billet caps and sonic tested. The rotating assembly is a Scat 4340 forged crank with straight-shot oiling on Scat 6.800" H-beam rods with ARP 2000 bolts and bushed pins, carrying Butler forged flat tops and Total Seal file-fit rings, balanced as a complete assembly.

Oiling is a Butler PRO 80 psi pump feeding a Canton road race / drag race pan — not a stock replacement. That is a deliberate choice for an engine expected to see sustained rpm and cornering load.

Self-tuning EFI, ready to run

Fuel is Holley Sniper 2 self-tuning EFI with the handheld monitor and a matched fuel line kit and regulator, paired with a full Holley HyperSpark ignition package — distributor, CD box and coil — so timing is under EFI control rather than fighting it. It was dyno tuned here before it shipped.

Specification — as built

Built the Butler way

Butler has been building Pontiac engines since 1974. Every engine that leaves here is assembled and blueprinted in our own shop and run on our own dyno before it ships — we don't ship an engine we haven't heard run. The dyno sheet goes with it.

If you want this combination in a different displacement, with a carburettor instead of EFI, or set up for a different car, talk to our tech department — that is what we do all day.