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Bolt-On Performance Parts Guide - Make Gains

Ways To Make Your Car Go Faster, Stop Shorter & Handle Better

Sean Haggai Apr 1, 2009
0904chp_01_z Chevy_vehicle_on_dyno Dyno_run 2/14

These days it has become easier than ever to generate good reliable horsepower. And if you're looking to crest the 500hp marker, then there really isn't a need to tear an engine down to the bare bones. That is, unless you are searching for something far grander and are prepared to lay down some hefty cash. First, what's a bolt-on? It's subjective. While many will argue that anything can be considered a bolt-on, we say the true defining feature of a bolt-on is it lets you get in and get out. This minimizes downtime and gets you out on the road and track faster with the added benefits of positive results. Moreover, when you take into account the bang-for-the-buck factor and the install-in-no-time attitude, it makes sense to consider a simple bolt-on.

Much like you, we're always in the mood for finding out what works. Besides, when you are guaranteed to pick up some power or some extra points on the skid pad with these bolt-on items, they are a shoe-in. We've done our homework and are presenting to you some of the finer bolt-on items that will increase power, won't break the bank, and will satiate your performance appetite. We compiled a list of the more popular and available off-the-shelf, bolt-on components that most anyone can handle and covered the gamut on everything from carburetor spacers to brakes to cylinder head swaps. Not only do we include the before and after numbers, but we also detail the price and where to pick one up for yourself. Basically, we did all the hard work for you, so you don't have to. If nothing else, our guide will give you an idea of what gains you can expect. Read on. You may find something you can bolt on this weekend and enjoy the same day.

Quick Notes
What we did

Generated a list of the more popular bolt-on items

Bottom line
Spent a couple days on the dyno to show you that the proof is in the numbers

Cost (Approx)
Starts at $88

0904chp_02_z Comp_cams_hooker_headers Comp_cams_gold_roller_rockers_and_hooker_super_competition_headers 3/14

Comp Cams Gold 1.6:1 Roller Rockers With 1 3/4-Inch Hooker Super Competition Headers

The Test
We threw out the old stamped steel rockers and replaced them with a set of Comp gold roller rockers. This would allow the 350 with the Weiand supercharger to take full advantage of all that extra air. We also swapped out the old 15/8-inch headers for 13/4-inch headers and threw it on Vaca Performance's chassis dyno for the results.

Max power: 327 hp @ 4,900
Max torque: 349 lb-ft @ 4,350
Average power: 237 hp
Average torque: 316 lb-ft

Max power: 342 hp @ 5,200
Max torque: 375 lb-ft @ 4,200
Average power: 252 hp
Average torque: 327 lb-ft
Difference: +30 hp; 26 lb-ft

Price: $950

Comp Cams

0904chp_03_z 1_inch_carburetor_spacer Hvh_4_hole_carburetor_spacer 4/14

1-Inch HVH 4-Hole Carburetor Spacer

The Test
More often than not, a spacer will do the trick and add power-and we proved it. The 9.8:1 iron-headed 396 big-block was topped off with a performer Edelbrock intake and a Holley 650-cfm carburetor. It made good, reliable power in almost stock trim on the engine dyno but made more with the spacer added.

Max power: 381 hp @ 5,000
Max torque: 442 lb-ft @ 3,100
Average power: 328 hp
Average torque: 427 lb-ft

Max power: 391 hp @ 5,000
Max torque: 451 lb-ft @ 4,200
Average power: 338 hp
Average torque: 439 lb-ft
Difference: +10 hp; +9 lb-ft

Price: $88


0904chp_04_z Holley_carburetor Holley_1050_hp_carburetor 5/14

Holley 1050 HP Carburetor

The Test
Swapped out Holley's 850-cfm carburetor for a heavier-breathing 1,050-cfm on (both HP series) on a 378ci race small-block. It was obvious that the increased cfm and added availability of fuel bumped up power and also increased torque across the board on the Superflow engine dyno.

Max power: 694 hp @ 7,900
Max torque: 485 lb-ft @ 6,500
Average power: 640 hp
Average torque: 478 lb-ft

Max power: 705 hp @ 7,800
Average power: 494 lb-ft @ 6,500
Max torque: 652 hp
Average torque: 486 lb-ft
Difference: +11 hp; + 9 lb-ft

Price: $800


0904chp_05_z Tuning_software Hp_tuners_vcm_software 6/14

HP Tuner's VCM Suite, Version 2.1

The Test
Z06 Corvette with FAST intake manifold, cold air intake, and throttle body with stock headers and exhaust. We hooked up HP Tuner's newest software to correct fuel and air mapping and ran the car on Westech Performance's chassis dyno.

Max power: 442 hp @ 6,024
Max torque: 478 lb-ft @ 4,298
Average power: 352 hp
Average torque: 412 lb-ft

Max power: 460 hp @ 6,330
Max torque: 484 lb-ft @ 4,423
Average power: 379 hp
Average torque: 419 lb-ft
Difference: +18 hp; +6 lb-ft

Price: $350 & Up

HP Tuner

0904chp_06_z Chevy_cylinder_heads Airflow_research_cylinder_heads 7/14

Airflow Research Cylinder Heads

The Test
A 355 ci test mule shortblock with GM Vortec heads making around 10.1:1 compression was swapped for AFR's 195 Eliminator Street heads. The new lungs paired with a Thumpr' cam dramatically improved air flow which is where the dramatic increase in power came from.

Max power: 396 @ 5,900
Max torque: 418 lb-ft @ 4,200
Average power: hp
Average torque: lb-ft

Max power: 453 hp @ 6,200
Max torque: 435 lb-ft @ 4,300
Average power: hp
Average torque: lb-ft
Difference: +57 hp; +17 lb-ft

Price: $1,400


0904chp_07_z Comp_cams_camshaft Comp_cams_hydraulic_roller 8/14

Comp Cams Hydraulic Roller XR294 (Nitrous Grind) 242/248, 540/562 With 110 Lobe Separation

The Test
We swapped out nitrous cams for a more aggressive 'stick from Comp. The new cam entered the 400ci Dart short-block with Dart 215 Pro 1 heads, a Dart single-plane manifold, and a Holley 830-cfm carburetor on top. During the run, a 125 shot of nitrous was sprayed on Westech's engine dyno.

Max power: 624 hp @ 5,500
Max torque: 630 lb-ft @ 5,100
Average power: 416 hp
Average torque: 500 lb-ft

Max power: 702 hp @ 5,900
Max torque: 684 lb-ft @ 5,200
Average power: 467 hp
Average torque: 529 lb-ft
Difference: +78 hp; +54 lb-ft

Price: $303

Comp Cams

0904chp_08_z Hooker_headers Hooker_super_comp_headers 9/14

Hooker Super Comp 2-Inch Headers With 18-Inch Collectors

The Test
Most often, a larger set of headers will increase flow and scavenge the exhaust more efficiently. The 540ci 10.5:1 big-block tested went from 13/4-inch headers with an 18-inch collector to a 2-inch Hooker Super Comp header with the same 18-inch collector. With a more "open" exhaust, power increased.

Max power: 667 hp @ 5,900
Max torque: 686 lb-ft @ 4,400
Average power: 564 hp
Average torque: 628 lb-ft

Max power: 702 hp @ 6,000
Max torque: 696 lb-ft @ 4,700
Average power: 574 hp
Average torque: 642 lb-ft
Difference: +35 hp; + 10 lb-ft

Price: $740

Hooker Headers

0904chp_09_z Demon_850_carburetor Demon_carburetion 10/14

Speed Demon 850

The Test
Using Westech's engine dyno, we swapped out a Road Demon 525 for a larger Speed Demon 825 on a mild 305 small-block with Vortec iron heads, Crane 1.5:1 roller rockers, and an Edelbrock Performer RPM air gap intake manifold.

Max power: 345 hp @ 6,000
Max torque: 341 lb-ft @ 4,400
Average power: 265 hp
Average torque: 320 lb-ft

Max power: 360 hp @ 6,000
Max torque: 341 lb-ft @ 4,100
Average power: 268
Average torque: 318
Difference: +15 hp; +0 lb-ft

Price: $450 & up

Demon Carburetion

0904chp_10_z Fast_fuel_injection Fast_fuel_injection_with_90mm_throttle Body 11/14

Fast Fuel Injection With 90mm Throttle Body

The Test
We swapped the carbureted setup on this LS1 with SLP cylinder heads and stock rockers to a more efficient FAST system. We also threw an MSD ignition on top with a 90mm throttle body and 55 lb/hr injectors.

Max power: 564 hp @ 6,500
Max torque: 504 lb-ft @ 5,200
Average power: 469 hp
Average torque: 488 lb-ft

Max power: 586 hp @ 6,400
Max torque: 518 lb-ft @ 5,000
Average power: 460 hp
Average torque: 484 lb-ft
Difference: +22 hp; +14 lb-ft

Price: $1,355


0904chp_11_z Big_brake_kit Classic_performance_sos_big_brake_kit 12/14

Classic Performance Products Sos Big Brake Kit

The Test
A '69 Chevy Nova was outfitted with CPP's Big Brake Kit. Out went the four-way drums in favor of a four-wheel disc set, including 13-inch discs in the front with 12-inch discs in the rear. The calipers were also swapped with new lines.

60-0 mph with OEM brakes: 188 feet
Peak deceleration force with OEM brakes: 0.89 g

60-0 mph with CPP kit: 128 ft
Peak deceleration force with CPP kit: 1.12 g's
Difference: -60 feet; +0.23 g

Price: $1,400

Classic Performance Parts

0904chp_12_z Ls1_intake_manifold Edelbrock_ls1_intake_manifold 13/14

Edelbrock Pro-Flo XT Intake For LS1

The Test
Edelbrock's been at it on the dyno with there new intake manifold and 90mm throttle body for the LS1. Compared with the stock LS6 intake on the company's 5.7L LS1 Corvette Z06 engine, the Edelbrock combo allowed massive amounts of air with the larger plenums and fuel with the throttle body to enter the engine.

Max power: 447 hp @ 6,500
Max torque: 428 lb-ft @ 4,500
Average power: 341 hp
Average torque: 396 lb-ft

Max power: 483 hp @ 6,498
Max torque: 431 lb-ft @ 4,993
Average power: 347 hp
Average torque: 400 lb-ft
Difference : +36 hp; +3 lb-ft

Price: $835

Edelbrock Corp.

0904chp_13_z Suspension_upgrade_kit Hotchkis_tvs_suspension_kit 14/14

Hotchkis TVS

The Test
A '69 El Camino with stock suspension was thrown through the slaloms, skidpad, and a barking test. Once the baseline was complete, Hotchkis's Extreme TVS kit was installed and gains were seen across the board. We added 1-inch Lowered Sport Coils, heavy-duty tie rod sleeves, a 13/8-inch front sway bar, a 15/16-inch adjustable rear sway bar, an adjustable rear trailing arm package, bushings, and hardware.

400-ft slalom: 40.6 mph
200-ft skidpad: 0.69 g
Braking: 185 ft

(With 17-inch wheels)
400-ft slalom: 44.1 mph
200-ft skidpad: 0.85 g
Braking: 177 ft
Difference: +3.5 mph; +0.16 g; -8 ft

Price: $1,853



Westech Performance Group
Mira Loma, CA



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