As stated in Part I, HPP was introduced to this project by a phone call from Jim Taylor who had just finished running the potent engine on the Bitner Automotive Inc. dyno to seek out its power limits. As a result, our two-part story includes the tear down, in Part I, which illustrated the wear created during the flogging and now we will discuss the components, machining and massaging required to produce 509 horsepower. View it as a reverse buildup if you will, as the photos will depict the motor coming apart rather than the usual bolting together.

This engine is tailor-made for the portly option-laden Second-Gen. T/A, which can tip the scales at nearly 4,000 pounds and has a carb height requirement due to the shaker hood scoop. The single-plane Holley Street Dominator intake manifold, which was employed on this engine, can be worked to produce the power levels seen in this story at the desired rpm while fitting under the hood. Whereas the Edelbrock Performer intake, another aluminum aftermarket piece that is known to fit under a shaker setup without a problem, will begin to drop off in power due to its dual-plane design, right in the rpm range where the Street Dominator thrives. Bear in mind that the Street Dominator for a Pontiac is no longer sold by Holley and will have to be found at swap meets or in classified ads.

Jim also related that the 850 Holley carb used in this buildup is his engine break-in carb and possibly a 750 carb would increase velocity further and may make more torque. This prospect opens the door for the Q-jet, which could be tried on this engine and would ensure that no mods whatsoever would be needed to the air cleaner base to fit the carb, as may be the case with the Holley.

The option to retain the stock valve covers is also important to Second-Gen. T/A owners because taller units often interfere with the stock brake booster and A/C brackets. This engine will allow the use of the stock valve covers.

Another enticement is that a 428 crank was fitted to the 400 block, making possible 440 cubes in an engine, which from all outward appearances is a 400. It's a sneaky way to be a street hero, when your 400 seemingly produces ungodly amounts of power for its perceived displacement.

The crank installation was accomplished by turning down the mains to 3.00 inches from 3.25. But that's not all that is required. The process has been mired in controversy for years with engine builders taking a stand on either side of the issue from a reliability standpoint. Turning down the crank is no big deal for this rpm range, but the method by which the width difference between the thrust bearings for the 400 and 428 is corrected is. Taylor explained, "The issue of the thrust bearing width difference between the 400 and 428 is commonly addressed by welding up the 428 crank's thrust face. I don't weld cranks. We use a heavily modified Olds V8 thrust bearing. Thrust is set at .008."

According to Taylor, "This engine combination works because the small ports combined with roller cam and the 4-inch stroke provide great torque and throttle response at all rpm points. With the chosen valvetrain components, stock valve covers can be retained and the height of the Street Dominator intake allows a shaker scoop to be reinstalled. Customers report that a 3.08 or 3.23 rear gear is all that is needed for peak performance. The only drawback is the 11.5:1 compression ratio, which requires 108 octane fuel."

Taylor reports that he can build a similar combination with 6X heads and 9.5:1 compression, and a slightly different cam, which will produce 25 less horsepower but retains the same torque figures and runs on pump gas. The cost for the 11.5:1 or the 9.5:1 engine is approximately $8,500 and requires no core from you. Read on to learn more.

Dyno Test with 1/2-inch Carb Spacer
On the Bitner Automotive Inc. dyno, the 440 produced 509.8 hp at 6016 rpm and 536.2 lbs.-ft. of torque at 4422 rpm and showed over 500 lbs.-ft. of torque all the way to 5200 rpm. This pull was performed with a 1/2-inch open spacer under the carb and it will still fit under the shaker scoop. With the carb bolted directly to the manifold about 5 hp was lost.

RPM HP TORQUE
4419 450.4 535.3
4422 451.5 536.2
4429 451.8 535.8
4435 452.8 536.2
4438 452.4 535.3
4446 453.7 536.0
4449 453.8 535.7
4451 453.8 535.4
4452 454.4 536.0
4459 454.7 535.6
4463 455.2 535.7
4470 455.4 535.1
4474 456.5 535.9
4481 456.5 535.1
4486 457.1 535.1
4501 457.7 534.1
4601 466.4 532.4
4716 474.2 528.1
4801 479.3 524.1
4916 484.8 518.0
5012 489.0 512.4
5126 495.5 507.3
5212 499.2 603.1
5302 503.9 499.2
5404 507.3 493.0
5500 509.6 406.6
5617 508.5 475.5
5706 508.2 467.8
5802 506.7 460.4
5900 509.0 453.1
6016 509.8 445.0
6111 508.2 436.7

Dyno Test with 2-inch Carb Spacer
With a 1-inch 4-hole spacer installed on top of an open 1-inch spacer, the 440 produced a whopping 513.8 hp at 6004 rpm with a maximum torque figure of 534.5 lbs.-ft. at 4406 rpm. Once again over 500 lbs.-ft. of torque was produced from the start of the run through 5200 rpm. This set up won't fit under a shaker but will work well in other models.

RPM HP TORQUE
4406 446.4 534.5
4405 447.7 533.6
4408 447.0 532.6
4412 447.8 533.1
4411 447.8 533.2
4417 447.8 532.4
4424 448.1 531.9
4428 448.1 531.5
4436 448.8 531.4
4440 449.0 531.2
4445 450.0 531.7
4449 450.5 531.8
4452 450.6 531.6
4454 451.1 531.9
4453 450.7 531.6
4503 455.0 530.8
4604 463.1 528.3
4700 470.4 525.6
4812 477.4 521.1
4904 462.6 516.9
5004 488.5 512.8
5117 494.8 507.9
5217 499.7 503.1
5310 503.1 497.6
5415 504.9 489.7
5512 507.4 483.4
5608 509.0 477.4
5710 510.2 469.2
5802 510.9 462.5
5911 513.0 455.8
6004 513.8 449.4
6105 513.7 441.9
440 Cubic-Inch Pontiac Engine Buildup Worksheet
Engine displacement:440 ci.
Bore/stroke: 4.188-in bore x 4.00-in. stroke
Block/crank combo: '68 400 block/'69 428 crank
Bore/stroke ratio: 1.05:1
Rod/stroke ratio: 1.66:1

Bottom End
 
Block description: Std. '68 400 with 2-bolt mains
Deck height: 10.230 in.
Formula to determine piston to deck height:
(1/2 stroke + rod C to C + pin hgt.=10.215 in.)
Piston to deck height: Piston is - .015 at TDC
Crank, brand, type, year: '69 428, set stroke at 4.00-in.
Balancer, brand: BHJ
Type: SFI approved steel-rubber
Rods brand, type: Crower Sportsman forged withfull-floating pin
Rod length: Stock 6.625-in.
Preparation: Measure pin and big end, visual inspection, wash
Bearings, brand, type: Michigan Clevite 77
Preparation: Measure, visual inspection
Pistons, brand, type: SRP Pontiac 428, 2 valve reliefs (5cc)
Preparation: Visually inspect, measure
Piston pins, brand, type: SRP full-floating
Retain piston pins in pistons: Double spiral locks
Rings, brand, type: Total Seal TS1 with 14 lb. tension oil ring
Preparation: Inspect, file fit end gaps, wash
Rod bolts/head bolts, brand: Crower rod bolts, ARP head bolts, ARP studs on front and rear mains


Oiling System
 
Windage tray brand, type: Pontiac full-length, oil holesenlarged
Crank scraper, brand, type: Jim Taylor Engine Service
Oil pan, brand, type: Moroso 8 qt. or modified GM
Oil pump. brand, type: Sealed Power


Heads
 
Casting number: #16
Chamber open/closed: Open
Head mods: Improve intake air flow to 240 cfm, port match
Blend bottom cut to bowl, shape up short turn radius
Combustion chamber volume: 66ccs.
Compression ratio: 11.5:1
Valves, brand, type: Nunzi high-flow 5.200 long
Intake size: Stock 2.11-in.
Exhaust size: Stock 1.77-in.
Retainers: Comp. Products Chrome-moly 10*
Keepers: Comp. Cams 10* with lash caps
Valve guides, brand, type: K-line liners, bronze
Valve seals, brand, type: Comp. Products Viton intakeand exhaust
Rocker arms, brand, stamped/roller: Crower full-roller
Rocker arm ratio: 1.5:1
Pushrods, brand: Smith Brothers, Chrome-moly .083 wall.
Diameter: 5/16-in
Length: 9.150 inches


Cam
 
Brand: TFX
Roller or flat tappet/hyd. or solid: Solid roller
Duration at .050: 250*/ 256*
Lift: .360-in lobe x 1.5 rocker = .540-in gross lift at
.020 lash = .520-in. net
Centerline: 110*
Lobe separation angle: 112*
Installed position: 110*
Lifters brand: Crower
Roller/hyd/solid: Solid roller
Valve springs, brand: Crower
Type: Dual w/damper
Seat pressure: 180 lbs.
Open pressure: 410 lbs.
Timing chain, brand: Hamburger Rollmaster
Type: 250-in. seamless double-roller


Induction
 
Carb, brand: Holley 4781-6 Double-Pumper
Size cfm: 850
Mods: Change power valve to 4.5


Jets
 
Primary: #80
Secondary: #78
Fuel pump: Carter mechanical 120 gph.
Fuel regulator: None with Carter mechanical pump
Fuel line size: 3/8-in.
Intake manifold, brand: Holley Street Dominator
Single/dual-plane: Single


Ignition
 
Distributor, brand, type: MSD Pro-Billet
Amplifier, brand: MSD
Coil, brand: MSD
Wires, brand, type: ACCEL 300+
Total timing: 36*
Initial advance: 14*
Mechanical advance: 22*
Vacuum advance: None


Exhaust
 
Headers, brand: Hooker Super Competition, coated
Primary tube diameter: 1 3/4-in.
Primary tube length: Aver. 28-in.
Collector size: 3-in.


Gaskets
 
Brand, type: Fel-Pro full engine set with #1016 head gaskets,
Mr. Gasket #502 intake, #550 exhaust
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