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Workhorse W20-W22 01-03 Performance Package Stage 1

Workhorse W20-W22 01-03 Performance Package Stage 1


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Kit Contents:

Ultrapower GM / Workhorse 8.1L Custom Tuning


Part # UPGM



UltraPower Custom Programming for the GM 8.1L 496cu has long been the ultimate performance modification you can make to your Workhorse/Chevrolet RV or truck with the highest power gains on the market, at the best price. Thousands of satisfied customers have reported fuel economy increases along with the addition of the extra pulling power when tackling steep grades. Also, less downshifting will occur as a result of the increased power. UltraPower Custom Tuning works very well on both stock engines and ones that have been upgraded with Banks Power Systems. Banks even admits their handheld AutoMind only changes one parameter within the computer, whereas UltraPower changes approximately 400 parameters. That is the difference between cookie-cutter and custom.

We are now offering Allison Transmission tuning on model years 2001-2004 W-Series. The main change you will notice is the transmission will shift into overdrive below 50 MPH when under light throttle. We also demand more load before it will downshift when pulling hills which means less downshifting. Increased line pressures also helps prolong the life of the transmission and optimizes the shift points. If you select this option you will pay an additional $350, however, if you return your original TCM we will credit you $250 back.


·         GM/Workhorse 8.1L Engine

·         GM Trucks with 8.1L Engine

·         Workhorse Motor Home Chassis from 2001-2010

·         Kodiak Chassis with 8.1L


·         Gains of 60-70 HP and 70-80 lb-ft TQ

·         Gains of 1/2 - 1.5 MPG

·         Downshifts less approaching hills



SPW8100 - UltraPower 8.1L Magnum Spark Plug Wires


Part# SPW8100 - UltraPower 8.1L Magnum Workhorse Spark Plug Wires


UltraPower Magnum Spark Plug Wires are patent protected because of the unique method of producing these wires which have extremely low resistance while maintaining very high noise suppression. The benefit of this invention is that full electrical energy from the ignition source is transmitted to the spark plug. The end result of the application of this method is increased horsepower, torque, fuel economy and a smoother running engine.



·         Patented Solid Stainless Steel Core Spark Plug Wires with RF Eliminator

·         The technology in these wires come straight from Nascar and is not available on the open market. They are made out of a patented zero OHM, solid core stainless steel wire wrapped by silver plated copper conductor wire and are outfitted with an RFI eliminator collar that guarantees no interference with radios.

·         These wires must be installed with GM factory heat shields which may be reused off your old wires.

·         High temperature silicone boots, 8mm jacket with fiberglass-reinforced braid that resists temperatures up to 500°F.

·         Increase power to the spark plug up to 400% over stock!

·         Adds up to 15HP on Big Block GM engines.

·         True Life-Time Lasting Wires, Life-Time Warranty!


41-101 - Set of 8 - Iridium Spark Plug For 8.1L


Part# 41-101 - Iridium Spark Plug for 8.1L

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WARNING: Products may contain one or more chemicals known in the State of California to cause cancer and/or birth defects or other reproductive harm. For more information, visit www.P65Warnings.ca.gov

  • Views: 10453
  • Product Code: KIT-WH22-1PERF-01-03
  • Availability: In Stock
  • $744.99

Please fill in Qty of each part desired

ID Image Product Name Model Qty Price
1 UltraPower GM / Workhorse 8.1L Custom Tuning (ECM Only) UltraPower GM / Workhorse 8.1L Custom Tuning (ECM Only) UP81 $595.00
3 SPW8100 - UltraPower 8.1L Magnum Spark Plug Wires SPW8100 - UltraPower 8.1L Magnum Spark Plug Wires SPW8100 $149.99