TCI Automotive - How to Get 674 lb-ft of Torque From a 540ci Big-Block

How To Get More Torque From 540Ci Big Block Block

After wiping down the cylinder walls with a light coat of oil, Twedt then went about stabbing the rod/piston assemblies into the Dart block.

After wiping down the cylinder walls with a light coat of oil, Twedt then went about stabb
Next, he torqued all the ARP rod bolts to the recommended value.
In terms of heads, Dart recommended their 310cc aluminum offerings (PN 19100112, $1,375 each). These rectangular-port heads came with a combustion chamber volume of 119 cc and flowed pretty good right out of the box, but Twedt saw room for improvement. As he recalled, “The Dart heads have a nice heart-shaped combustion chamber that provides good swirl and helps generate good low-mid lift flow numbers. In my experience, the 540 street engines like anywhere from 10.2-10.5:1 compression. With our combination we fell a little short of that, so we milled approximately 0.020-inch off the heads to net us our desired ratio. I also hand-massaged the piston domes and flame-notched them to remove any sharp edges to get us the best flame travel across the piston tops as possible. With this minimal machine work, we ended up with a little better runner/chamber combination, and the 10.5:1 compression we wanted.”

In terms of heads, Dart recommended their 310cc aluminum offerings (PN 19100112, $1,375 ea

The fully assembled Dart Pro 1 heads are made from strong 355-T6 aluminum and feature a big 2.250-inch intake and 1.880-inch exhaust valves. Twedt did do a mild amount of porting to the cross-section and short turn radius. The key was to do just enough to improve flow and cylinder fill, but not slow down the airspeed at low to mid-lift point. He also performed a five-angle radius valve job. The heads were then secured using an ARP stud kit and sealed with a Fel-Pro gasket (PN 1047, $46).

The fully assembled Dart Pro 1 heads are made from strong 355-T6 aluminum and feature a bi
The 540 was internally balanced, so we went with this Rattler Torsional Vibration Absorber from TCI Automotive (PN 870005, $386). The rattler is designed to absorb, rather than just dampen vibrations and is SFI 18.1 certified.

The 540 was internally balanced, so we went with this Rattler Torsional Vibration Absorber
Oil is life, especially in a big-block that may see some lateral g’s. To keep the dead dinosaurs moving, we picked up this high-volume pump from Moroso (PN 22185, $112). This pump is designed for an 8-inch deep pan, and the pickup is fully welded in place.

Oil is life, especially in a big-block that may see some lateral g’s. To keep the dead din

To complement our oil pump, we went with this fully baffled six-quart pan from Moroso (PN 20403, $263). It features a kicked-out sump for improved oil control and an integrated windage tray. We bolted it in place using a Fel-Pro gasket set and stainless fasteners from our ARP accessory bolt kit (PN 535-9601, $139).

To complement our oil pump, we went with this fully baffled six-quart pan from Moroso (PN
Pushrod length is critical, but often overlooked. As Twedt says, “We check every engine we build to make sure that we have the exact valvetrain geometry and pushrod length. I used my adjustable pushrod tool from COMP, set it close to what it should be, and then adjusted it from there until I had the right pattern across the tip of the valve where the roller tip rides.” For this build we ended up needing 7.700-inch and 8.750-inch Lunati 4130 (0.080-inch wall) pushrods ($8.50 each).

Pushrod length is critical, but often overlooked. As Twedt says, “We check every engine we
One key player in our valvetrain were these Lunati roller lifters (PN 72431LUN, $599). They have a vertical bar and are perfect for dropping into blocks designed for flat tappets. Twedt also checked piston-to-valve clearance. It came in at +0.150 inch on both the intake and exhaust. Again, reliability is in the details.

One key player in our valvetrain were these Lunati roller lifters (PN 72431LUN, $599). The

Rounding out our roller valvetrain were these aluminum 1.7:1 ratio rockers from Lunati (PN 85350LUN, $360). CNC-machined from aircraft heat-treated aluminum alloy they are then tumble-polished to reduce stress risers and fitted with needle-bearing trunions.

Rounding out our roller valvetrain were these aluminum 1.7:1 ratio rockers from Lunati (PN
“As far as the top end goes, we selected the Victor Jr. (PN 2902, $250) single plane because it works great with big-inch big-blocks. Some would say a dual plane would make more torque, and they’re probably correct on a 427-502 inch engine, but a 540 is a torque monster anyway, so we didn’t mind giving up a few pound-feet down low for a few more ponies up top,” Twedt says.

“As far as the top end goes, we selected the Victor Jr. (PN 2902, $250) single plane becau
Topping off our Victor Jr. was this Holley 4150 HP (PN 0-80496-1, $740). At 950 cfm it’s more than capable of feeding our 540ci Dart mill and has many of the features, like the fuel bowls of its bigger Dominator cousin.

Topping off our Victor Jr. was this Holley 4150 HP (PN 0-80496-1, $740). At 950 cfm it’s m

To reliably light the fire, we went with this PerTronix Flame-Thrower with Ignitor III electronic ignition module (PN D7100700, $238). CNC-machined from 6061-T6 billet, this distributor has adapted well to maintain peak energy throughout the entire rpm range as well as a built-in rev limiter. For a coil, we picked up their matching 60,000V Flame-Thrower HC E-Core (PN 60103, $64).

To reliably light the fire, we went with this PerTronix Flame-Thrower with Ignitor III ele
Here it is set up and ready to rock the dyno at Westech Performance. To complete the package, we bolted on a set of ceramic thermal-coated Doug’s headers (PN D319, $697). The 2-inch primaries and 3.5-inch collectors will help the 540 breathe properly while the 16-gauge construction and 3/8-inch flange means they will last. Before firing up the Superflow 902 dyno, we dumped a few gallons of 91 octane in the tank.

Here it is set up and ready to rock the dyno at Westech Performance. To complete the packa
After dialing in the timing to 35 degrees and swapping out the jets (76/76), Westech’s Steve Brulé nailed down a best pull of 680 hp at 5,700 rpm and 669 lb-ft of twist at 4,600. More important, though, is how the 540 ci made over 600 lb-ft from the roll in at 3,000 rpm and stayed there almost to 6,000 rpm. The consensus was that we needed slightly stiffer valvesprings on the Dart heads to slow the fall off after 5,700 rpm. Then again as a street engine it will rarely ever need to rev past 6,000 rpm.

After dialing in the timing to 35 degrees and swapping out the jets (76/76), Westech’s Ste

Out of curiosity, we slid a Wilson 1-inch open spacer underneath the Holley carb.
Our reward was a very small gain over most of the torque curve (peak gain of 5 lb-ft) and a slight bump in the horsepower number (peak gain of 5 hp) from 4,500 rpm up. If you have the hood clearance and can score a good deal on a spacer, then there’s no downside to running one in this case. But even without the spacer this 540 ci is guaranteed to provide many smile-inducing street miles.CHP

Our reward was a very small gain over most of the torque curve (peak gain of 5 lb-ft) and

SOURCE
Wiseco Performance Products 7201 Industrial Park Blvd. Mentor OH 44060 440-951-6600 www.wiseco.com	Edelbrock 2700 California St. Torrance CA 90503 310-781-2222 www.edelbrock.com
Pertronix 440 East Arrow Highway San Dimas CA 91773 909-599-5955 www.pertronix.com	Holley 1801 Russellville Road Bowling Green KY 42101 270-781-9741 www.holley.com
Westech Performance 11098 Venture Drive Unit C Mira Loma CA 91752 951-685-4767 www.westechperformance.com	ARP (Automotive Racing Products) 1863 Eastman Avenue Ventura CA 93003 800-826-3045 www.arp-bolts.com
Doug's Headers 440 East Arrow Highway San Dimas 91773 909-599-5955 www.pertronix.com	Lunati 11126 Willow Ridge Drive Olive Branch MS 38654 662-892-1500 www.lunatipower.com
Moroso 80 Carter Drive Guilford CT 06437 203-453-6571 www.moroso.com	Fel-Pro 26555 Northwestern Highway Southfield MI 48033 248-354-7700 www.federal-mogul.com
Dart Machinery 353 Oliver Street Troy MI 48084 248-362-1188 www.dartheads.com	JR Competition Engines 760-745-4540 www.jrcompetition.com
TCI 151 Industrial Drive Ashland MS 38603 888-776-9824 www.tciauto.com

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How to Get 674 lb-ft of Torque From a 540ci Big-Block - Fire In The Hole