Subscribe to the Free
Newsletter

Nitrous-Fed Big-Block makes 937 hp!

The Mad Adder: The only thing better than a big-inch big-block is one with a big shot of nitrous!

Richard Holdener Apr 28, 2017 0 Comment(s)
View Full Gallery

When it comes to power production, nothing beats a power-adder. Everyone has their favorites, of course, but no matter what you choose, once you sample the power from nitrous or boost it’s dang hard to go back to an NA configuration. If Street Outlaws is any indication, power-adders are alive and well and living under the hood of most every racer out roaming the streets. Power-adders have become so prevalent that many engine builders now offer dedicated crate combinations designed specifically for use with nitrous and/or boost. Heck, both Ford and GM offer crate engines designed specifically for power-adders. Knowing this, you can imagine how excited we were when the good folks over at BluePrint Engines (BPE) let us know that they were adding yet another combination to their extensive lineup of ProSeries crate engines. Not just any engine mind you, but a big-block Chevy version sporting 540 cubic inches!

Even before uncrating the new power-adder ready combination, we knew several things about the BPE big-block. Like all of the BPE crate engines, this 540 had already seen dyno time and included a dyno printout to verify the rated power output. To make the BBC combo power-adder ready several performance upgrades were made to the big Chevy. Starting with their own big-bore, four-bolt block, they added a 4340 forged steel crank, forged H-beam rods, and matching forged aluminum pistons. When combined with the aluminum rectangle port BBC heads (PN PS8013) with 119cc chambers and 2.300/1.880-inch valves, the result was a very power-adder friendly compression ratio of 8.5:1. Finishing off the big-inch bruiser was a healthy solid roller cam that checked in with 0.652/0.652-inch lift, 255/262-degrees duration, and 114-degree LSA.

Knowing customers would be adding their own power-adders to the mix, BPE supplied the 540 in long-block form. To run this big-block on the dyno we had to install a few key components, namely the intake, carb, and distributor. For induction, we chose a Holley 950-cfm Ultra XP carb feeding a Weiand Team G single-plane intake. MSD stepped up with a billet distributor and 6AL ignition box to ensure plenty of spark energy. Though the engine had been run previously on the dyno, we ran it through a series of break-in cycles before establishing our baseline. After dialing in the air/fuel ratio and timing, the 540 responded with peak numbers of 649 hp at 6,100 rpm and 629 lb-ft of torque at 4,500 rpm. By adding cubic inches to your typical 454 or 496, the 540 already offered additional performance, even before the power-adder. We loved the power output and broad torque curve offered by the 540, but even more so because we knew the reduced static compression ratio meant the big-block was primed and ready to gnaw on some nitrous.

First on the list of power-adders for the big-block was nitrous oxide. Though many kits are available for a 4150-style carburetor application, we chose the Zex Perimeter Plate wet system. Designed to be sandwiched between the carburetor and intake, the Perimeter Plate features 12 equally spaced injection points to evenly distribute the fuel and nitrous mixture. The plate also featured inlet (jet) fittings for both the nitrous and fuel. The Zex kit was adjustable from 100-300 hp; we chose jetting to supply a solid 250 hp. The kit also featured a 10-pound bottle, a pair of solenoids, and all the hoses and fittings necessary to install the nitrous system.

Having previously run the 540 big-block to establish our baseline, it was time to get mad with our power-adder. After warming the bottle to ensure sufficient bottle pressure (over 900 psi), we activated the nitrous on the 540. All we can say is wow, as the combination of the Zex system and 540-inch big-block thumped out 937 hp and 891 lb-ft of torque. What was even cooler was the fact that the combination did it on the first hit, without a hint of drama. We love it when a plan comes together, but we were just getting started. We plan on running boost, boost, then more boost after the initial success with our 540 big-block affectionately nicknamed The Mad Adder.

540 Big Block Chevy 2/14

01. Chock full of power-adder goodness, the BluePrint Engines 540 long-block featured lowered compression, aluminum heads, and a healthy solid roller cam. All we needed was the proper induction system and distributor to get it going.

540 Big Block Chevy Power Adders 3/14

02. To establish our baseline numbers before the power-adder, we installed this Weiand Team G single-plane intake.

Nitrous Dyno Test 540 Big Block Chevy 4/14

03. The Team G intake flange was designed to accept a 4150-style carburetor. To ensure plenty of air and fuel flow, we installed a Holley 950-cfm Ultra XP carburetor.

Msd Billet Distributor 5/14

04. Obviously, power production (especially under nitrous) requires plenty of spark so we installed this MSD billet distributor. The distributor was combined with a 6AL ignition controller.

Nitrous Dyno Test 540 Big Block Chevy 6/14

05. Run in naturally aspirated trim, the lower-compression 540 produced 649 hp at 6,100 rpm and 629 lb-ft of torque at 4,500 rpm. Now we were ready for our power-adder.

540 Big Block Chevy Power Adders 7/14

06. Though we plan to test a variety of power-adders, we started our power-adder adventure with a Zex Perimeter Plate nitrous system. We installed longer carb studs to mount the plate and solenoids.

540 Big Block Chevy Perimeter Plate 8/14

07. The Perimeter Plate featured 12 equally spaced injection points and inlets for both the nitrous and fuel.

Zex Kit Nitrous 9/14

08. The Zex kit featured a pair of solenoids to supply nitrous and fuel to the plate.

Zex Perimeter Plate 10/14

09. The power output supplied by the Zex Perimeter Plate kit was adjustable using the supplied nitrous and fuel jets. Our kit was adjustable from 100-300 hp. We set up the system for an extra 250 hp.

Power Output Zex 11/14

10. The Perimeter Plate design ensured even distribution of the fuel and nitrous to maximize safe power production.

Nitrous Dyno Test 540 Big Block Chevy 12/14

11. The square-flange, Perimeter Plate was sandwiched between the intake and the Holley 950-cfm Ultra XP carburetor.

Nitrous Dyno Test 540 Big Block Chevy 13/14

12. Run with 250hp jetting (after heating the bottle), the Mad Adder big-block thumped out 937 hp and 891 lb-ft of torque. With power-adder number one safely in the books, we glanced longingly over at the 8-71 supercharger just begging to be installed.

Nitrous Dyno Test Results 540 Big Block Chevy 14/14

13. Run in naturally aspirated trim, the Mad Adder 540 was no slouch, thumping out peak numbers of 649 hp and 629 lb-ft of torque. After adding the Zex Perimeter Plate nitrous, the peak numbers soared to 937 hp and 891 lb-ft (using 250hp jetting). Note from the power curves that we manually retarded the timing by 10 degrees to ensure safe nitrous use. The loss of timing had a decided effect on the power output prior to activation of the nitrous. We loved how easy it was to exceed 900 hp with this power-adder big-block and can’t wait to run some boost on this baby.

Photography by the Author

Sources

Zex
Memphis, TN 38118
888-817-1008
www.zex.com
Holley
Bowling Green, KY 42101
866-388-5120
www.Holley.com
MSD
El Paso,
915-857-5200
MSDPerformance.com
ARP
Ventura, CA 93003
800-826-3045
www.ARP-BOLTS.COM

MORE PHOTOS

VIEW FULL GALLERY
X

COMMENTS

Connect With Us

Get Latest News and Articles. Newsletter Sign Up

sponsored links

subscribe to the magazine

get digital get print
CLOSE X
BUYER'S GUIDE
SEE THE ALL NEW
NEWS, REVIEWS & SPECS
TO TOP