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Sparco EVO2 Seat and Seat Rail Installation Instructions

Sparco EVO2 seats are designed for people heavier than 200lbs. These seats are a little wider than the Sparco EVO seats.

I chose to use the HardBar seat mounts, as the Sparco mounts don't work in the C5. The C5 mounting points are not centered with the seat. This requires a modified part. HardBar makes a complete assembly for race seat installation.

(603) 682-8073 or (603) 472-7164

Included in the kit from Hardbar are the following parts:

  • 2 Rails
  • 4 uprights screws
  • 4 M8x20 Button Head Cap
  • 2 M10x25mm Socket Head Cap Screws
  • 6 M10x30mm Socket Head Cap Screws
  • 8 M10x25mm Button Head Cap Screws
  • 4 steel cylindrical "gender bender" nuts
  • 8 M8 fender washers
  • 20 M10 flat washers
  • 12 M10 Nylock nuts

The following tools are required:

  • 6mm hex key
  • 8mm hex key
  • 10mm hex key
  • 15mm wrench or socket
  • 17mm wrench

[NOTE: Click the thumbnail pictures to view a higher resolution version. Use your browser's "Back" button to return here]

This photo is of the mounting brackets and hardware from Gary at Hardbar. This is one set. I purchased two sets, one for the driver's side and one for the passanger side. (2000 and newer C5 Corvettes with Active Handling require a modified version. Be sure to clarify the year and model of your Corvette when you order).

This photo is of the interior of my 97 C5 coupe.
I will be installing the Sparco EVO2 seat in the drivers position.

Do the Job


  1. Remove seat nut covers by extracting the plastic pin on the front seat nut covers and then pulling cover towards the front of car. Remove the 4 seat nuts with the 15mm wrench (or socket). NOTE: Picutre shown is with seat removed
  2. After removing the stock seat, including disconnecting the electrical connector, you will also need to remove the cover between the side rail and the seat belt cover. After removing the seat belt cover, remove the stock set belt using a star socket.
  3. Thread the 10mm plain nut a few turns on the 10mm screw and screw assembly into a gender bender nut (about 3-4 turns). This is creating a "jam nut" to be used as a wrenching tool to tighten the gender bender. Using the 8mm hex key and the 17mm wrench, hold the hex key and tighten nut against the gender bender. The gender bender needs to be tight but not excessively so (23 Ft.-Lbs.). Now tighten the gender bender nut using the 17mm wrench on the nut. Remove 10mm nut, and screw from gender bender nut by holding 8mm hex and loosening the nut. Thread "gender bender" nuts over seat studs and hand tighten. (4 places) Repeat for all other gender bender nuts.
  4. Assemble one rail and vertical seat brackets to the outside of the rail then to the seat. Install assembled bracket to inside or right side of the seat. Use the M10x25 button head cap screws, nuts and washers (under nut) for the uprights. (You must tighten the inside or right side hardware before installing seat. There is NO easy way to tighten the hardware on the inside of the seat after seat is installed, not enough room). Use the M8x20 Button Head Cap (Longer screws will make installation easier) to mount the HardBar assembled bracket to the seat. Be sure to add 4 finder washers. This will take up the space between the vertical bracket and the seat!
  5. Install each side to seat using the M8 screws, small washers and fender washers. Use 1 small washer under the screw head and 4 washers on the seat side. Again, do not tighten outer or left side seat assembly yet!
  6. Install in car using the M10x30 for the sub belt cross bar and M10x25 for the other end with 2 small and 1 large washer under each screw head (the large washer goes towards the aluminum slots). For 5-point harness, install cross bar in back and use the M10x30 screws (shown below the M10x25 screws are for the front in this case). For 6-point harness, use cross bar in front with appropriate screws. Check seat position for comfort and adjust as desired. This may take several tries before you have the correct seat position. Use additional finder washers if hardware bottoms out in gender bender. If you are using a Sparco EV02, EVO3 or similar seat that is much wider than the standard EVO, you can use the uprights on the outside of the rails as shown below. Seat must be tight and must not move!
  7. Remove assembly and tighten all screws.
  8. Install lap belt to unused holes in rail using M10 screws, nuts and washers.
  9. Install sub belt to Front cross bar.

The finished product!

Make sure to check all fasteners for tightness after first 1.5 hours of use.
Now go win your event!

This page was last updated on October 1, 2001 by Matt Graham


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