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SPWEX8100 - UltraPower 8.1L Extreme Magnum Spark Plug Wires

On SALE! SPWEX8100 - UltraPower 8.1L Extreme Magnum Spark Plug Wires

Made in America

Verified to have been manufactured in the USA


Order Shipment Notice: 

Most orders are shipped within 24 hours from the order date. Orders placed on the weekend or after cutoff on Friday, and orders placed on select holidays are processed on the next business day. Please see our shipping terms for more information.

Part# SPWEX8100 UltraPower 8.1L Extreme Magnum Workhorse Spark Plug Wires


These are the mack-daddy of all spark plug wires! Never burn another wire again!

UltraPower Extreme 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. You do not use the factory metal heat shields with these wires.


  • 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.
  • Wires are sleeved from top to bottom with high temperature fiberglass/acrylic socks that will withstand up to 1500º F & 1000º F continuously.
  • Eliminates the need for the metal boot shield.
  • These wires were engine dyno tested for 2500 hours under wide open throttle conditions and were the only wires that could hold up to those conditions. Even ceramic wires wouldn't last.
  • 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!


  • Workhorse chassis with 8.1L (2001-2011)
  • Workhorse chassis with 6.0L (2004-2006)
  • All GM vehicles with 8.1L (Silverado, Sierra, Avalanche, Yukon XL)
  • Industrial applications with 8.1L (Generators, Forklifts, Pumps, Compressors, etc)

Comparison and installation video by one of our customers:

Would the 41-101 Iridium Spark Plugs be the correct plugs to use in a 2001 Chevrolet 2500HD with a 8.1L Vortec Engine? If so what should the gap be? ( Ken Schenk, 07/20/2023 )
Yes, this would be correct. If using our Magnum wires you would just leave them at the factory gap of .060. ( Support )
Are these plug wires (SPWEX8100 - UltraPower 8.1L Extreme Magnum Spark Plug Wires) the best option for my 2001 Chevrolet 2500HD with 8.1L Vortec engine? ( Kenton Schenk, 07/20/2023 )
If you want the maximum heat protection then these would be it. The pickups don't generally burn wires like the RV's do so you probably only need the regular SPW8100 though, same wires just without the high temp heat socks. ( Support )
I ordered the extreme magnum plug wires for my 2006 w22 chassis 8.1
. I notice they mention metal plug wire protectors are not required . Is this due to not fitting over plug boot or can I use as additional protection ?
I have a 2006 Tiffin allegro bay ..
Obviously came with factory metal shields with delco wires .
( Michael, 06/14/2022 )
We don't recommend using the metal heat shields with the Extreme Magnum Plug wires . ( Support )
What spark plugs would you recommend with these wires? (2007 W-22 Chassis with 8.1L engine on Fleetwood motorhome) ( J. Ruiz, 08/10/2021 )

41-101 - Iridium Spark Plug For 8.1L & 7.4L

( Support )
Are theses for my motorhome ? ( Richard E. Carroll, 09/15/2019 )
Yes, these are correct. They will fit any 8.1L in any application.  ( Support )

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 The state of California requires that this warning be posted for people purchasing products that reside in California.

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

VIN Verification Service Item

This product allows for a VIN verification service.

  • VIN part verificaion is a service that we provide free of charge when a part is purchased.
  • When you provide your VIN below we will personally verify your part selection by your VIN before shipment of your order.
  • This helps ensure that this is the correct part for your vehicle.
  • This is not an automatic VIN check, it is done by a parts specialist once order is placed.
  • We can only VIN verify vehicles back to model year 1996, if older we can help but can't guarantee fitment.
  • If you would like to have your part selection verified before purchase please call or email us.

Shipping Insurance Notice

NOTICE: For orders outside of United States

If you are placing an order to ship outside the United States, Shipping Insurance will be required and added automatically at checkout.


  • Views: 76344
  • Brand: UltraPower
  • Product Code: SPWEX8100
  • Availability: 14
  • $371.25
  • $275.00

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