Bracket Talk
2 x 3 chassis cert

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https://drr.infopop.cc/eve/forums/a/tpc/f/75460652/m/4597061796

October 09, 2021, 06:44 AM
Holytown
2 x 3 chassis cert
I’ve been searching the internet and can’t find what I’m looking for. Probably because it is so uncommon these days. Does anyone know the minimum ET cert that a 2 x 3 main frame all moly tube chassis door car with FC cage can certify to? I’m assuming 7.50 is minimum as long as wall thicknesses are correct. 99% sure 6.00 requires Round tube everywhere.
October 09, 2021, 07:32 AM
green1
My old car is 2x3 frame and was told at one time a funny car cage, steel floor on drivers side and steel firewall would get it to 7.50. Been a while so I may be remembering details a little wrong.
October 09, 2021, 10:07 AM
maliciousintent
Check the rule book.
October 09, 2021, 11:56 AM
David Covey
quote:
Originally posted by Holytown:
I’ve been searching the internet and can’t find what I’m looking for. Probably because it is so uncommon these days. Does anyone know the minimum ET cert that a 2 x 3 main frame all moly tube chassis door car with FC cage can certify to? I’m assuming 7.50 is minimum as long as wall thicknesses are correct. 99% sure 6.00 requires Round tube everywhere.


SFI 25.1 and 25.2 (25.1 covers up to 2800 lbs and 25.2 covers up to 3200 lbs)
Neither shows the use of 2x3 tubing.Even if it is chrome moly. So it will need to be 1 5/8 or 1 1/2 round tube depending on build configuration.

7.50 is quickest your chassis will certify and the 2x3 needs to be .083 CM or MS.

Hope this helps

Dave


"It is usually futile to try to talk facts and analysis to people who are enjoying a sense of moral superiority in their ignorance." -Thomas Sowell
October 09, 2021, 02:11 PM
Holytown
Appreciate you looking into it Dave. Thanks!
October 09, 2021, 03:59 PM
J Olejniczak
I have a 91 Dodge Daytona with CM Chassis and FC cage and the rail from the front of the 4 link brackets to the front is a 2x3 rail. It is certified 25.4 to 7:50.
October 10, 2021, 01:11 PM
David Covey
quote:
Originally posted by J Olejniczak:
I have a 91 Dodge Daytona with CM Chassis and FC cage and the rail from the front of the 4 link brackets to the front is a 2x3 rail. It is certified 25.4 to 7:50.


you are welcome Holytown..

J Olejniczak..

Right

Dave


"It is usually futile to try to talk facts and analysis to people who are enjoying a sense of moral superiority in their ignorance." -Thomas Sowell
October 11, 2021, 08:12 AM
Holytown
quote:
Originally posted by J Olejniczak:
I have a 91 Dodge Daytona with CM Chassis and FC cage and the rail from the front of the 4 link brackets to the front is a 2x3 rail. It is certified 25.4 to 7:50.


Thanks J
October 12, 2021, 12:31 PM
J Olejniczak
Holytown: Do yourself a favor and get a SFI book. It will save you trouble making sure you meet specifications. I had the book and 2 different inspectors looked at things differently and had to go back twice to pass. I do have a X support under the transmission and extra tubing in the seat area now as well. Trans pulls out inside the car now.
October 12, 2021, 12:53 PM
David Covey
quote:
Originally posted by J Olejniczak:
Holytown: I had the book and 2 different inspectors looked at things differently


As most here know I do chassis certs for IHRA. I too have ran into this issue. I rebuilt a friends S/G roadster after he tore up the front end. I then certified the car. He goes to Houston to race a divisional and had to get a NHRA cert. I get called that the car would not pass. The side bays had diagonals 3/4" diameter. The inspector wanted 5/8" X bracing. Even though the SFI stated either would work.
He had the SFI and even got the senior tech over to look at the car. He was told that it was whatever the guy doing the inspection wanted and would not over rule him.

So he brings the car back to me after missing the race and spends what it take to make the dumbass who could not read happy..

My policy (and I have been backed up by Frank and Baker) is show me where I'm wrong and I will have no issue certifying the car.
We all have opinions but some have better reading skills than others. I have no issues with being proven wrong, I am willing to learn.

Dave


"It is usually futile to try to talk facts and analysis to people who are enjoying a sense of moral superiority in their ignorance." -Thomas Sowell
October 12, 2021, 05:51 PM
inferno camaro
2x3 here 7.50 cert. I didn't think they even made cm 2x3 tube. I just googled it and sure enough there it is. I was told by an nhra inspector years ago that my frame rails couldn't be cm because there wasn't cm square tubing.