NHRA regulations thread

This comes up often enough. I'll start out with this quick reference chart Angry posted.

http://promod.nhra.com/userfiles/file/Tech/2019%20ET%20Quick%20Reference%20Charts.pdf

Relevant stuff for Challenge cars I've been accumulating. I'll add to it as I have the time.

Relocated battery

• Relocated = anywhere other than stock location.
• Must be in a vented container or separate compartment from driver.
• Must have cut-off switch accessible and labeled from outside rear of car.
• 3/8" bolts to secure it.

Roll bar rules

• All convertibles faster than 13.50
• All fixed roof faster than 11.50

Can't bend roll bar tube? Buy one on Amazon for under $50! Punch the P/N into Summit's website for the full measurements to make sure it fits. Other sizes also available.

Driveshaft/Axle Hoops

• All cars with slicks, no matter how slow
• All cars faster than 10.00
• Beefy 2"x1/4" full loop flat bar (heavy)

Nitrous

• Tank must have DOT certification. It's like 5 or 10 years. You can get this done as a hydro-test facility (think fire extinguisher servicers) for under $20
• Bottles inside passenger compartment must have blow-down tube that exits the compartment
• Must have safety burst disk
• Driver must have SFI flame suit.

Tires

• 11.99 and quicker: any tubeless tires must have metal screw-in valve stems
• All street tires minimum 1/16" tread depth

Good resources I've been accumulating:

Guide to passing Tech

SFI guide on seating and belts

So no mother bottle in the back of my wagon. Got it.

Found this link. It has some good reading. 

http://dragsite.tripod.com/id5.htm

Excellent information. Thank you for posting this. 

Solid info.. Thanks for taking the time to make it easier to find!

Finding a copy of the NHRA rule book has been difficult in the past.  I found a link to the 2020 rule book today.

https://nationaldragster.s3.amazonaws.com/Rulebooks/2020_NHRA_Rulebook_11_01/pubData/source/2020_NHRA_Rulebook_11_01.pdf

From the link address I wonder if it's a misconfigured AWS account.  Download while you can.

Relocated battery

• Relocated = anywhere other than stock location.

That is an odd one, as the intent is right, but if your battery is mounted in front of the firewall and stays in front it is not considered "relocated."

Probably worth another blurb on jackets, even if you are slow, if you are 13.99 to 10.0 and non OEM turbo or SC you need a 3.2a/1 jacket. Easy to forget it.

Stampie (FS) said:

Finding a copy of the NHRA rule book has been difficult in the past. 

2020 was the first year NHRA published their rulebook online. Finding it now is as simple as typing "NHRA rules" into a search bar; glorious!

Here is 2021
https://nationaldragster.s3.amazonaws.com/Rulebooks/2021%20NHRA%20Rulebook_21_01_28.pdf

Relevant sections for the Challenge are 21 & 22. Some additional language and clarifications about how and when certain regulations apply can be found in section 4A.

In reply to gumby (Forum Supporter) :

Just make sure you measure your ride height with the driver.  Thanks for sending me on my search with our conversation yesterday.

In reply to Stampie (FS) :

Ride height?  I've been surfing through the NHRA rule book and haven't found ride height restrictions yet. What am I missing? My Harbor Freight jack won't go under the sides of the car though.

DeadSkunk (Warren) said:

In reply to Stampie (FS) :

Ride height?  I've been surfing through the NHRA rule book and haven't found ride height restrictions yet. What am I missing? My Harbor Freight jack won't go under the sides of the car though.

I think they are worried about this section:

It is in the frame section so slightly unclear to me if the rule is referencing the frame only or if it also includes the 'body' as well. 

There sure don't look like 3 inches under that bumper to me. 

In reply to Robbie (Forum Supporter) :

Thanks Robbie. If that 's the applicable section then I meet it by a little bit.

In reply to DeadSkunk (Warren) :

I noticed that Gumby was setting his ride height at 3 inches.  Told him I’d have go go lower than my planned 3.5 inches. That’s what got me looking. Think I’ll just beat him anyway at 3.5 inches. 

Stampie (FS) said:

Think I’ll just beat him anyway at 3.5 inches. 

I thought this thread was for information about NHRA regulations, not smack talk! When are you going to finish gathering parts and start building?

3" is the regs but feel free to stage with the front spoiler, it's just extra ET. You won't get flagged and not allowed to run for it.

gumby (Forum Supporter) said:

Stampie (FS) said:

Think I’ll just beat him anyway at 3.5 inches. 

I thought this thread was for information about NHRA regulations, not smack talk! When are you going to finish gathering parts and start building?

Which happens first - Stampie starts or Angry finishes?

Paul_VR6 (Forum Supporter) said:

3" is the regs but feel free to stage with the front spoiler, it's just extra ET. You won't get flagged and not allowed to run for it.

Why is it extra ET? The start beam and finish beam should be the same height right?

In reply to Robbie (Forum Supporter) :

I’m thinking weight transfer lifts the spoiler to clear the beam.  Now I’m coming up of some way to cheat the system more.

3" is damn low folks.... unless it's all spoiler/fascia. Any "street" car/truck set that low is garbage at the track.

Now I'm going to fab a "pecker extender" and beat you all.

Stampie (FS) said:

In reply to Robbie (Forum Supporter) :

 

I’m thinking weight transfer lifts the spoiler to clear the beam.  Now I’m coming up of some way to cheat the system more.

 

But the light is at 3". You would have to attempt to double stage before the other guy lights the first bulb or auto start is going to light you up red.

You stage on the spoiler instead of the tire but the down track  beams are on the body and you have now added 12+" to the length of the track. The good part is if you do this you are only shooting yourself in the foot.

google beam tripper and enjoy the read for more stupid drag racing "secrets"

What's the reason behind requiring metal valve stems on cars running under 12 seconds?

In reply to thatsnowinnebago (Forum Supporter) :

Old hold over from when the tires sucked and to get forward thrust was to do a wheelie. Plus most of the stock and super stockers are running 50psi in the front tire if not more.

Ranger50 said:

3" is damn low folks.... unless it's all spoiler/fascia. Any "street" car/truck set that low is garbage at the track.

Now I'm going to fab a "pecker extender" and beat you all.

Patent pending beam tripulator.  Pivot is at the bumper.  Blue is an actuator.  Actuator is operated by clutch switch in my case with a manual override for staging.  Clutch in tripulator is down.  Clutch out actuator pushes down and raises the tripulator.