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Re: 8.50 Cage Questions [Re: CMcAllister] #3281976 01/10/25 07:43 PM 01/10/25 07:43 PM
Joined: Dec 2003 Posts: 24,047 Here J jcc No soup for you!!!
jcc No soup for you!!! J Joined: Dec 2003 Posts: 24,047 Here	Originally Posted by CMcAllister The "D" bar has to be there when the cage is welded to the floor using plates. Recommended on everything. The rocker bar has to be there if the stock floor and/or firewall have been fooled with, except for a 6 sq.ft. section of removable floor for a trans tunnel. The exception is cars with a frame rail on the outside of the cage structure. i.e. GM G bodies. I much prefer using tubing, rectangle or round, to provide "outriggers" from the frame/frame ties to the inside of the rocker panel, front and rear, sectioned up into the floor, effectively making that structure part of the cage, and visa versa. Do that and use X bars in the doors and the rocker bar can be deleted. It is there for side impacts and situations where the car could get into the air and come down on the wall in that area, folding the floor up into the driver. To additionally clarify IMO a shortcoming I see, there is no triangulation in the main hoop above the "C: bar, that would be useful in a rollover if the either main hoop upper corner makes a hard impact with the pavement, etc. Additionally bars "A" & " E:" in their normal lengths and secured only at their ends. provides little side impact protection both in robustness and the area protected, hence my thinking of extra vertical bars to tie A& E into the added sill bar the OP originally asked about, and continue that thinking also from the sill bar into the SFC. Last edited by jcc; 01/11/25 09:42 PM. I forbid my content here from being learned and used by artificial intelligence systems.

Re: 8.50 Cage Questions [Re: jcc] #3282145 01/11/25 09:17 PM 01/11/25 09:17 PM
Joined: Dec 2005 Posts: 12,824 Fulton County, PA C CMcAllister Mr. Helpful
CMcAllister Mr. Helpful C Joined: Dec 2005 Posts: 12,824 Fulton County, PA	I might note...the diagrams and specs shown in the rulebook are the minimum requirements for a bar or a cage to get you to 10.00/135, depending on your car. It's certainly not everything I would want to see. Beyond that, an appropriate SFI spec kicks in. Triangulation of all of the major parts of the chassis, so everything supports everything else, from front to back, is fundamental. For example the rear "B" bars should be crossed to form an X from the top of the hoop to the framerails or floor. It's more work. But it makes much better use of those bars than individual, parallel bars. If the results don't match the theory, change the theory.

Re: 8.50 Cage Questions [Re: CMcAllister] #3282152 01/11/25 09:38 PM 01/11/25 09:38 PM
Joined: Dec 2003 Posts: 24,047 Here J jcc No soup for you!!!
jcc No soup for you!!! J Joined: Dec 2003 Posts: 24,047 Here	I largely agree, but I can see cases where one diagonal brace is enough of an improvement by itself, but an upgraded x instead is not adequate bang for buck, unless maybe rule book required. I forbid my content here from being learned and used by artificial intelligence systems.

Re: 8.50 Cage Questions [Re: CMcAllister] #3282158 01/11/25 10:36 PM 01/11/25 10:36 PM
Joined: Aug 2003 Posts: 44,135 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 44,135 Bend,OR USA	I don't think roll cages are required until you go quicker than 9.99 ET and or over 135.00 MPH, both in the 1/4 mile Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: 8.50 Cage Questions [Re: Cab_Burge] #3282166 01/11/25 11:41 PM 01/11/25 11:41 PM
Joined: May 2012 Posts: 1,939 South Bend John Brown top fuel
John Brown top fuel Joined: May 2012 Posts: 1,939 South Bend	Originally Posted by Cab_Burge I don't think roll cages are required until you go quicker than 9.99 ET and or over 135.00 MPH, both in the 1/4 mile Newer car, maybe. On older cars, I believe the break is 10.99. July 19th should be "Drive Like Rockford Day". R.I.P. Jimmie.

Re: 8.50 Cage Questions [Re: John Brown] #3282175 01/12/25 01:49 AM 01/12/25 01:49 AM
Joined: Aug 2003 Posts: 44,135 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 44,135 Bend,OR USA	Originally Posted by John Brown Originally Posted by Cab_Burge I don't think roll cages are required until you go quicker than 9.99 ET and or over 135.00 MPH, both in the 1/4 mile Newer car, maybe. On older cars, I believe the break is 10.99. No it is not, my pump gas 1971 Duster had a five point CM roll bar in it and ran 9.990 and 10.00 a bunch of times at many NHRA sanction races here in the northwest. 11.49 and quicker down to 10.000 in the 1/4 mile require a NHRA legal five point roll bar The cut off use to be 11.99 but that was changed for the new muscle HP pony cars that would run in the mid 11s way back some time ago Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: 8.50 Cage Questions [Re: John Brown] #3282197 01/12/25 10:09 AM 01/12/25 10:09 AM
Joined: Jan 2004 Posts: 8,969 fredericksburg,va C cudaman1969 Itch Nutz
cudaman1969 Itch Nutz C Joined: Jan 2004 Posts: 8,969 fredericksburg,va	Originally Posted by John Brown Originally Posted by Cab_Burge I don't think roll cages are required until you go quicker than 9.99 ET and or over 135.00 MPH, both in the 1/4 mile Newer car, maybe. On older cars, I believe the break is 10.99. Book and ‘class racers’ say 9.99 for a cage, then you got to have a net too. 8.50 is when all the Xs come into play, 7.50 is CM only, but remember you’ll have TWO cages, built cage and the car itself, both tied together is a real plus.

Re: 8.50 Cage Questions [Re: cudaman1969] #3282215 01/12/25 11:58 AM 01/12/25 11:58 AM
Joined: Jan 2003 Posts: 19,664 Las Vegas Al_Alguire I Live Here
Al_Alguire I Live Here Joined: Jan 2003 Posts: 19,664 Las Vegas	A lot of incorrect info on here, but the internet is chock full of incorrect info on this subject. For instances you can run mild steel to 7.50, at 7.49 Moly is required. A rollbar is required at 11.49, for a convertible at 13.49. If its a newer stock production car since 2014(think Demon, Hellcat, RTesla Plaid, GT500, ZL1, Z06 etc) they can go 9.00/150 before they are required a cage. Any car from 2008-2013 can run as quick as 10.00 before they are required to run a cage. Provided they are unaltered OEM installed antilock brakes, OEM airbag functions, OEM stock frame\unibody construction, including OEM floors and firewall, as well as all other OEM safety-related systems must be functioning as per manufacturer’s specifications. Tires used may be other than OEM, but they must be DOT-approved As for the engineering what has been shown is the MINIMUM required. If you feel your advanced degree forces you to do more then by all means feel free, but it MUST meet the minimum requirements for the ET(8.50 minimum) being run,.That's why as you go faster and faster the requirements get more and more stringent. Below 8.50 SFI is involved with the specifications and depending on weight and desired minimum ET the requirements vary. But even for a lowly rollbar there are tubing diameter and wall thickness requirements. This stuff is all readily available on NHRA in the form of a rulebook. Until you go faster than 8.50 then the SFI books for chassis cert are available through SFI. And no they are not free. "I am not ashamed to confess I am ignorant of what I do not know." "It's never wrong to do the right thing"

Re: 8.50 Cage Questions [Re: Al_Alguire] #3282247 01/12/25 01:50 PM 01/12/25 01:50 PM
Joined: Dec 2005 Posts: 12,824 Fulton County, PA C CMcAllister Mr. Helpful
CMcAllister Mr. Helpful C Joined: Dec 2005 Posts: 12,824 Fulton County, PA	Originally Posted by Al_Alguire A lot of incorrect info on here, but the internet is chock full of incorrect info on this subject. For instances you can run mild steel to 7.50, at 7.49 Moly is required. A rollbar is required at 11.49, for a convertible at 13.49. If its a newer stock production car since 2014(think Demon, Hellcat, RTesla Plaid, GT500, ZL1, Z06 etc) they can go 9.00/150 before they are required a cage. Any car from 2008-2013 can run as quick as 10.00 before they are required to run a cage. Provided they are unaltered OEM installed antilock brakes, OEM airbag functions, OEM stock frame\unibody construction, including OEM floors and firewall, as well as all other OEM safety-related systems must be functioning as per manufacturer’s specifications. Tires used may be other than OEM, but they must be DOT-approved As for the engineering what has been shown is the MINIMUM required. If you feel your advanced degree forces you to do more then by all means feel free, but it MUST meet the minimum requirements for the ET(8.50 minimum) being run,.That's why as you go faster and faster the requirements get more and more stringent. Below 8.50 SFI is involved with the specifications and depending on weight and desired minimum ET the requirements vary. But even for a lowly rollbar there are tubing diameter and wall thickness requirements. This stuff is all readily available on NHRA in the form of a rulebook. Until you go faster than 8.50 then the SFI books for chassis cert are available through SFI. And no they are not free. All true. I try to talk in generalities and to the stuff most guys will be dealing with - older cars, hardtops and sedans, likely unibodies. This stuff was all based strictly on ET breaks, until it became easy to buy a car off the showroom that would go into the 10s or even the 9s. Safety features and not wanting to turn them away at the local tracks caused them to make requirements year make and model dependent. A "bar" is what would typically be called a 6 or 8 point, lacking the halo and A pillar bars in the roof, to the windshield, the dash and down to the floor. A "cage" is all of that and everything else needed as ETs go down and speeds go up. Different requirements for each. Rulebooks are $10. Want to run quicker than 8.50, sfifoundation.com for the spec on your application. Keep one in the top of your tool box. A typical, backhalf, Super Stock style car with original floors and firewall in front of the rear seat would go to a 25.5 spec to go 8.50 to 7.50. Plenty of cars built to the 7.50 spec even if they aren't planning on going that quick. Safety and resale value are two big reasons. Last edited by CMcAllister; 01/12/25 01:56 PM. If the results don't match the theory, change the theory.

Re: 8.50 Cage Questions [Re: Al_Alguire] #3282262 01/12/25 02:21 PM 01/12/25 02:21 PM
Joined: Dec 2003 Posts: 24,047 Here J jcc No soup for you!!!
jcc No soup for you!!! J Joined: Dec 2003 Posts: 24,047 Here	"As for the engineering what has been shown is the MINIMUM required." I may be wrong here, but it seems to me, the evolution of the rulebook over decades is mostly a reactive one, seldom proactive, and we should not categorically dismiss reasoned and valid suggested easy/quick/cheap improvements that the rulebook has yet to address, A lot of pain/injuries/etc could have been avoided had these current rules been in place many decades ago had those in charge had the foresight or racers had not only sought the minimums required. But it's a free country, choose wisely is still the game. I forbid my content here from being learned and used by artificial intelligence systems.

Re: 8.50 Cage Questions [Re: Al_Alguire] #3282280 01/12/25 04:51 PM 01/12/25 04:51 PM
Joined: Jan 2004 Posts: 8,969 fredericksburg,va C cudaman1969 Itch Nutz
cudaman1969 Itch Nutz C Joined: Jan 2004 Posts: 8,969 fredericksburg,va	Originally Posted by Al_Alguire A lot of incorrect info on here, but the internet is chock full of incorrect info on this subject. For instances you can run mild steel to 7.50, at 7.49 Moly is required. A rollbar is required at 11.49, for a convertible at 13.49. If its a newer stock production car since 2014(think Demon, Hellcat, RTesla Plaid, GT500, ZL1, Z06 etc) they can go 9.00/150 before they are required a cage. Any car from 2008-2013 can run as quick as 10.00 before they are required to run a cage. Provided they are unaltered OEM installed antilock brakes, OEM airbag functions, OEM stock frame\unibody construction, including OEM floors and firewall, as well as all other OEM safety-related systems must be functioning as per manufacturer’s specifications. Tires used may be other than OEM, but they must be DOT-approved As for the engineering what has been shown is the MINIMUM required. If you feel your advanced degree forces you to do more then by all means feel free, but it MUST meet the minimum requirements for the ET(8.50 minimum) being run,.That's why as you go faster and faster the requirements get more and more stringent. Below 8.50 SFI is involved with the specifications and depending on weight and desired minimum ET the requirements vary. But even for a lowly rollbar there are tubing diameter and wall thickness requirements. This stuff is all readily available on NHRA in the form of a rulebook. Until you go faster than 8.50 then the SFI books for chassis cert are available through SFI. And no they are not free. Yep a lot of ignorant sh it on here.

Re: 8.50 Cage Questions [Re: cudaman1969] #3282455 01/13/25 12:21 PM 01/13/25 12:21 PM
Joined: Jan 2003 Posts: 19,664 Las Vegas Al_Alguire I Live Here
Al_Alguire I Live Here Joined: Jan 2003 Posts: 19,664 Las Vegas	FWIW an SFI book is $38..You will need a different one for each SFI spec you are chasing. Again weight and ET dependent. One other tidbit the correlation from 1/8 to 1/4 mile ET's does not really line up well, especailly for advanced ET stuff... "I am not ashamed to confess I am ignorant of what I do not know." "It's never wrong to do the right thing"

Re: 8.50 Cage Questions [Re: Al_Alguire] #3282596 01/14/25 08:58 AM 01/14/25 08:58 AM
Joined: Jan 2003 Posts: 5,782 Hot Rod Ridge FastmOp master
FastmOp master Joined: Jan 2003 Posts: 5,782 Hot Rod Ridge	Put a Procharger on that Hemi

Re: 8.50 Cage Questions [Re: FastmOp] #3282610 01/14/25 10:25 AM 01/14/25 10:25 AM
Joined: Aug 2003 Posts: 4,787 On the parachute mount N n20mstr master
n20mstr master N Joined: Aug 2003 Posts: 4,787 On the parachute mount	asking on here you going to get 100 different answers. IT IS ALWAYS a better fit going through the dash, Cant go wrong with going by the SFI book. Whenin doubt, ask the guy that is going to cert it, he is the one with the final say. However IF you follow the SFI book, you cant go wrong. I would ge the 25.5 SFI book and go by that becasue you have stock firewall and floor. Obviously you dont need the funny car cage, BUT it can be added later and the car will be worth more at resale time whith this type of cage in it Last edited by n20mstr; 01/14/25 10:26 AM. ....BAD A$$ STREET CAR.....

Re: 8.50 Cage Questions [Re: n20mstr] #3282625 01/14/25 11:37 AM 01/14/25 11:37 AM
Joined: Mar 2006 Posts: 10,155 MI, usa dvw I Live Here
dvw I Live Here Joined: Mar 2006 Posts: 10,155 MI, usa	I contacted the Division 3 Tech Director several times during construction. If you do it by E mail then there is a record of what they told you. Doug

Re: 8.50 Cage Questions [Re: n20mstr] #3282639 01/14/25 12:57 PM 01/14/25 12:57 PM
Joined: Dec 2005 Posts: 12,824 Fulton County, PA C CMcAllister Mr. Helpful
CMcAllister Mr. Helpful C Joined: Dec 2005 Posts: 12,824 Fulton County, PA	Originally Posted by n20mstr asking on here you going to get 100 different answers. IT IS ALWAYS a better fit going through the dash, Cant go wrong with going by the SFI book. Whenin doubt, ask the guy that is going to cert it, he is the one with the final say. However IF you follow the SFI book, you cant go wrong. I would ge the 25.5 SFI book and go by that becasue you have stock firewall and floor. Obviously you dont need the funny car cage, BUT it can be added later and the car will be worth more at resale time whith this type of cage in it There are additional bars required in the chassis to meet this spec. Not just a funny car cage. Always easier to build it that way to begin with rather than try to add on later. Also usually easier to take the roof off, rather than try to get all that tubing in there with it on the car.. Especially for a tall driver. If the results don't match the theory, change the theory.

Re: 8.50 Cage Questions [Re: CMcAllister] #3282649 01/14/25 01:55 PM 01/14/25 01:55 PM
Joined: May 2004 Posts: 12,548 Taxes & Virus's R-US, NY Dragula OP I Live Here
Dragula OP I Live Here Joined: May 2004 Posts: 12,548 Taxes & Virus's R-US, NY	I had to cancel my chassis upgrade appointment due to cash flow concerns. My daughter died this past Friday, and its been absolutely devastating. Beyond the emotional distress, there is a financial obligation as well. So with that said, I probably won't be on here as much as I deal with this somehow....Sorry to post this but its been super difficult lately. https://my.gather.app/remember/kelsey-kudla '70 Cuda,...605 EFI Hemi Street Car (6.20 best pass, 1.33 60ft) https://www.youtube.com/watch?v=WYw6RA-k5Bk (6.25 at 108.75mph from inside car) https://www.youtube.com/watch?v=3zQEb9uxFng (6.25 at 108mph from outside car) https://www.youtube.com/watch?v=JCvfzsC4NgM (9.9) '66 Barracuda AWB Stretched nose Blown 440 Car in build stage '71 Duster Drag Car 400 Low Deck 512 best 6.002 at 115.44mph https://www.youtube.com/watch?v=Znuo3jMUXTk

Re: 8.50 Cage Questions [Re: Dragula] #3282650 01/14/25 02:06 PM 01/14/25 02:06 PM
Joined: May 2019 Posts: 185 W. Pa U usp4u member
usp4u member U Joined: May 2019 Posts: 185 W. Pa	I am terribly sorry to hear of your loss. Prayers sent to you and your family.

Re: 8.50 Cage Questions [Re: Dragula] #3282651 01/14/25 02:07 PM 01/14/25 02:07 PM
Joined: Feb 2003 Posts: 1,134 Massillon, Ohio C cudatom super stock
cudatom super stock C Joined: Feb 2003 Posts: 1,134 Massillon, Ohio	Sorry for your loss. As someone that's lost a child I fully understand what you are going through. God Bless Ok

Re: 8.50 Cage Questions [Re: Dragula] #3282681 01/14/25 05:05 PM 01/14/25 05:05 PM
Joined: Dec 2003 Posts: 24,047 Here J jcc No soup for you!!!
jcc No soup for you!!! J Joined: Dec 2003 Posts: 24,047 Here	I can't begin to imagine the heartbreak you must feel. We will be here whatever the need, whenever the time is right for you. Focus on what is important. I forbid my content here from being learned and used by artificial intelligence systems.

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