sytyguy
Moderated User
Should have put this up a LONG time ago, but it slipped my mind. Anyhow, here's the breakdown on the autocross and it's classes.
SAFETY TECH - We are performing our own tech since we're running the show, so we'll be lenient to an extent. The main concerns are that you wear a seat belt (driver and passenger), wear a helmet (we'll have spares), remove any loose items from the vehicle, keep your arms inside while running (driver and passenger - windows down is fine), and pass a general safety tech that will cover things such as battery hold down, tire check, suspension check, and brake check. Essentially, if you drove it to Nats, you're probably okay. :tup:
PAX TECH - At the same time as safety tech, we'll observe your mods and assign you a PAX index. I realize that we don't have definitive testing to support a verified or relavent improvement of certain mods, but since we're not handing out money, I figured y'all would be okay with us guesstimating. I'll break down the mods below, but at PAX tech, you'll be give a number followed by a PAX assignment (e.g. 07A or 11C). The PAX assignment is for internal use.
Here's the way it works. A stock truck starts out with a PAX of .850 and what that means is that if you run a 40.000 second run, your actual time will be 34.000 seconds. With each mod (listed below) you add on, your PAX index gets higher (closer to 1.000) resulting in less of a difference between actual time and PAX time. For instance, a fully modded truck with 295/315 race tires, rear bar, upgraded brakes, a big turbo, built engine, coilovers, etc... could come in at a PAX of .980, meaning that a 40.000 second run will be a 39.200 second run after PAX index is applied (keep in mind that a modded truck should have a much faster raw time). Make sense?
Stock Truck: .850
MODS
.010 - Rear sway bar.
.015 - Upgraded front discs (C5, C6, CTS-V, etc...). Rear discs are no penalty.
.015 - Any tire exceeding 255mm in width.
.020 - Any tire with a treadwear of 140 to 200.
.040 - Autocross/Track tires (regardless of width).
.025 - Coilover suspension (of any manufacturer). Includes coilovers with stock A-Arms.
.020 - Rear coilover suspension or 3-Link or Watts Link setup.
.005 - 20G turbo.
.010 - Turbo between 52MM and 66MM.
.015 - Turbo greater than 66MM.
.005 - Vortec heads.
.010 - Race heads (Brodix, Pontiac, etc...)
.020 - Extreme weight savings (visual inpection only)*
* This is reserved for those trucks that are estimated to be 3200lbs or less. Since we can't enforce weight penalties without a set of scales, we'll have to rely on visual inspection only, but it'll be obvious.
So, let's say you have a truck with larger street tires, a rear sway bar, a 60MM turbo, and vortec heads. You would get a PAX of .890. That means that if a stock truck runs a 40.000 raw time and the aforementioned modded truck runs a 38.300 raw time, the stock truck would actually win as it PAXs at a 34.000 (vs the modded truck's 34.087).
I know that this list isn't perfect, but it's a starting point for us and something I'll develop over the coming years (some things added, some changed) until we have a proven list of modifiers for autocrossing our trucks. This list will also help those wanting to mod to see what to mod (and how important handling is instead of power).
SHOWDOWN - One of our attendees has graciously donated his rental car as the showdown car. Essentially, this is a neutralizer where the best driver wins. Same car, same course....it's up to you. Want to enter, LMK.
SAFETY TECH - We are performing our own tech since we're running the show, so we'll be lenient to an extent. The main concerns are that you wear a seat belt (driver and passenger), wear a helmet (we'll have spares), remove any loose items from the vehicle, keep your arms inside while running (driver and passenger - windows down is fine), and pass a general safety tech that will cover things such as battery hold down, tire check, suspension check, and brake check. Essentially, if you drove it to Nats, you're probably okay. :tup:
PAX TECH - At the same time as safety tech, we'll observe your mods and assign you a PAX index. I realize that we don't have definitive testing to support a verified or relavent improvement of certain mods, but since we're not handing out money, I figured y'all would be okay with us guesstimating. I'll break down the mods below, but at PAX tech, you'll be give a number followed by a PAX assignment (e.g. 07A or 11C). The PAX assignment is for internal use.
Here's the way it works. A stock truck starts out with a PAX of .850 and what that means is that if you run a 40.000 second run, your actual time will be 34.000 seconds. With each mod (listed below) you add on, your PAX index gets higher (closer to 1.000) resulting in less of a difference between actual time and PAX time. For instance, a fully modded truck with 295/315 race tires, rear bar, upgraded brakes, a big turbo, built engine, coilovers, etc... could come in at a PAX of .980, meaning that a 40.000 second run will be a 39.200 second run after PAX index is applied (keep in mind that a modded truck should have a much faster raw time). Make sense?
Stock Truck: .850
MODS
.010 - Rear sway bar.
.015 - Upgraded front discs (C5, C6, CTS-V, etc...). Rear discs are no penalty.
.015 - Any tire exceeding 255mm in width.
.020 - Any tire with a treadwear of 140 to 200.
.040 - Autocross/Track tires (regardless of width).
.025 - Coilover suspension (of any manufacturer). Includes coilovers with stock A-Arms.
.020 - Rear coilover suspension or 3-Link or Watts Link setup.
.005 - 20G turbo.
.010 - Turbo between 52MM and 66MM.
.015 - Turbo greater than 66MM.
.005 - Vortec heads.
.010 - Race heads (Brodix, Pontiac, etc...)
.020 - Extreme weight savings (visual inpection only)*
* This is reserved for those trucks that are estimated to be 3200lbs or less. Since we can't enforce weight penalties without a set of scales, we'll have to rely on visual inspection only, but it'll be obvious.
So, let's say you have a truck with larger street tires, a rear sway bar, a 60MM turbo, and vortec heads. You would get a PAX of .890. That means that if a stock truck runs a 40.000 raw time and the aforementioned modded truck runs a 38.300 raw time, the stock truck would actually win as it PAXs at a 34.000 (vs the modded truck's 34.087).
I know that this list isn't perfect, but it's a starting point for us and something I'll develop over the coming years (some things added, some changed) until we have a proven list of modifiers for autocrossing our trucks. This list will also help those wanting to mod to see what to mod (and how important handling is instead of power).
SHOWDOWN - One of our attendees has graciously donated his rental car as the showdown car. Essentially, this is a neutralizer where the best driver wins. Same car, same course....it's up to you. Want to enter, LMK.
