Author Topic: SFI chassis specs  (Read 6725 times)

Offline samotorsport

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SFI chassis specs
« on: December 09, 2022, 03:44:41 PM »
Hey guys , I am looking for the latest SFI chassis rules , anybody has the full booklet as a PDF and willing to share with me ?
Thanks in advance
Sam

Offline Paul New

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Re: SFI chassis specs
« Reply #1 on: December 10, 2022, 08:40:11 AM »
They are $38 at https://sfifoundation.com/drag-racing-chassis/

And there are many to choose from
DRAGSTERS
SFI Spec 2.1C Rear Engine Dragster (Top Alcohol/Methanol) – 5.99 Seconds & Quicker
Effective Date: December 3, 2021
SFI Spec 2.2D Front Engine Dragster – 5.99 Seconds & Quicker
Effective Date: December 3, 2021
SFI Spec 2.3U Rear Engine Dragster (Top Fuel) – 4.99 Seconds & Quicker
Effective Date: May 7, 2021
SFI Spec 2.4D Front Engine Dragster – 6.00 to 7.49 Seconds
Effective Date: December 3, 2021
SFI Spec 2.5E Rear Engine Dragster – 6.00 to 7.49 Seconds
Effective Date: December 3, 2021
SFI Spec 2.6C Front Engine Dragster – 7.50 Seconds & Slower
Effective Date: December 3, 2021
SFI Spec 2.7E Rear Engine Dragster – 7.50 Seconds & Slower
Effective Date: December 3, 2021

FUNNY CARS, ALTEREDS AND ROADSTERS
SFI Spec 10.1G Funny Car Roll Cage (Alcohol, Advanced ET, Nostalgia, etc.)
Effective Date: December 3, 2021
SFI Spec 10.2A Altered Car Roll Cage – 6.00 to 7.49 Seconds
Effective Date: December 3, 2021
SFI Spec 10.3B Altered and Funny Car Roll Cage – 7.50 Seconds & Slower
Effective Date: December 3, 2021
SFI Spec 10.4B Side Steer Roadster Roll Cage – 7.50 Seconds & Slower
Effective Date: December 3, 2021
SFI Spec 10.5A Nitro Fuel Funny Car Chassis – 4.99 Seconds & Quicker
Effective Date: October 31, 2013 (edited Oct. 1, 2014)

FULL BODIED CARS
SFI Spec 25.1K Full Bodied Car Tube Chassis – 7.49 Seconds & Quicker; 2,800 lbs. Maximum
Effective Date: July 2, 2021
SFI Spec 25.2E Full Bodied Car Tube Chassis – 6.00 to 7.49 Seconds ET; 3,200 lbs. Maximum
Effective Date: July 2, 2021
SFI Spec 25.3D Full Bodied Car with Aftermarket Body Shell and Tube Frame, OEM Body Shell and OEM Frame with OEM or Modified Floorpan and Firewall, or Uni-Body with OEM or
Modified Floorpan and Firewall Roll Cage – 6.50 to 7.49 Seconds ET; 3,600 lbs. Maximum
Effective Date: July 2, 2021
SFI Spec 25.4D Full Bodied Car Tube Chassis – 7.50 to 8.49 Seconds; 3,600 lbs. Maximum
Effective Date: July 2, 2021
SFI Spec 25.5E Full Bodied Car Stock or Modified/OEM Floorpan and Firewall with OEM Frame or Uni-Body Construction – 7.50 to 8.49 Seconds; 3,600 lbs. Maximum
Effective Date: July 2, 2021
SFI Spec 25.6A Full Bodied Car Stock / Truck or Modified/OEM Floorpan and Firewall with OEM Frame or Uni-Body Construction – 7.99 to 8.49 Seconds; 5,000 lbs. Maximum
Effective Date: July 2, 2021

Offline samotorsport

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Re: SFI chassis specs
« Reply #2 on: December 10, 2022, 09:29:14 AM »
Ah , thanks a lot, i didn t know this .
So I will go and order them there.
I will also check if there is a specific one for jr dragsters.

Thank you very much.
Best regards
Sam

Offline Finnish Fireball

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Re: SFI chassis specs
« Reply #3 on: July 18, 2023, 09:00:59 AM »
Has any of you guys recerted your chassis this year? I was told there's a new amendment in SFI 2.6C forcing to change this cage center bar to oval pipe??? Doesn't make any sence to me if it's true. Cutting off the old one and welding in a thinner piece will only weaken the structure in my opinion. Not to mention how the previous welds have hardened the pipe.

I'm fast. I can make five mistakes while others think.

Offline gordon

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Re: SFI chassis specs
« Reply #4 on: July 20, 2023, 08:14:10 AM »
Just got mine recerted for (6.00 and slower) not sure of that change, as mine has always been the oval/aero cross section.

Offline tcoupekyle

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Re: SFI chassis specs
« Reply #5 on: July 21, 2023, 01:00:39 PM »
I got a 6.0 cert this year and there was no mention of needing oval tube.

Offline THE FRENCHTOWN FLYER

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Re: SFI chassis specs
« Reply #6 on: July 21, 2023, 09:03:10 PM »
maybe its merely a proposed change?

Offline denverflatheader

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Re: SFI chassis specs
« Reply #7 on: July 22, 2023, 08:36:09 AM »
I checked the SFI website and the last revision shown for Spec. 2.6c was done in December 2021.  The only mention of Oval Tubing in that revision was related to the minimum acceptable wall thickness for mild steel round and oval tubing is 0.118 inches.

Per the SFI website, SFI reviews exiting specifications on a periodic basis to ensure the specs remain current to changing conditions.  SFI has in the past held their review meeting at the Performance Racing Industry Trade Show (PRI) usually held around the first week in December.  When it is closer to the meeting date, they will probably post a meeting agenda on their website of the topics and potential revisions to discuss.  You could check the agenda when posted in December to see any discussions related to Spec 2.6c.

Just click on the SFI website link posted above by Paul, go to the top menu line-item Tech & Safety to see the last Chassis Spec Tech Advisories and Updates currently listed.

 

Offline Finnish Fireball

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Re: SFI chassis specs
« Reply #8 on: July 22, 2023, 09:05:39 PM »
This is the latest, see line #2 second hoop center bar spec and tell me what do you think this major/minor axis means actually?
Maybe I'm just a dumb foreigner but I don't get it.



« Last Edit: July 22, 2023, 09:08:24 PM by Finnish Fireball »
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Offline denverflatheader

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Re: SFI chassis specs
« Reply #9 on: July 23, 2023, 08:41:46 AM »
Yes, I see that Number 2 Rear Hoop Center Brace.  See lll.1.f. and the Table to the right showing If Roll Cage Height 18 inches or less or exceeds 18 inches. 

The Table shows the same Specs for either 6 point Roll Cage Height.  I think I'm seeing 1. major axis x .049 or .857 minor axis x .049. 

Yes, you are not confused. That translates to an ellipse (oval) from my understanding as well, with 1.0 inch being the longer dimension of the ellipse and 0.857 inch being the shorter dimension of the ellipse.

If those are the dimension of the ellipse, right away I would think it would be too small for the top center brace you are questioning.  1 inch tubing in the helmet area of the roll cage is usually for the helmet bar. 

When Number 2 item mentions See lll.1.f. - what information is that?  Perhaps it will help answer the question if it shows a diagram.

Offline Finnish Fireball

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Re: SFI chassis specs
« Reply #10 on: July 23, 2023, 09:12:25 PM »
Thanks Denver, picture lll.1.f shows the chassis bars numbered, and #2 is that center bar this spec sheet refers to. I totally agree 1" bar there oval or not is stupid. This can't be right.
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Offline Oldboy

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Re: SFI chassis specs
« Reply #11 on: July 24, 2023, 04:11:57 AM »
Maybe the important point is that all sizes mentioned in SFI specs. are 'minimum acceptable' sizes.
I guess that if the 1" dimension was 1.625" and the 0.857" was also 1.625" (i.e. round) that would be acceptable, or is that too simple?
I agree, all rather too complicated.

Offline Finnish Fireball

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Re: SFI chassis specs
« Reply #12 on: September 07, 2023, 11:11:21 PM »
Oldboy got it right, it's just the minimum requirement and the current bigger tube is just fine. Case closed.
I'm fast. I can make five mistakes while others think.