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Roll cage question for a Coupe #1400415 03/10/13 06:51 PM 03/10/13 06:51 PM
Joined: Jan 2003 Posts: 7,490 Minnesota Hemi_Joel OP master
Hemi_Joel OP master Joined: Jan 2003 Posts: 7,490 Minnesota	Is there a way to build a NHRA legal (8.50 and slower) cage for a coupe like this without the rear down bars poking thru the rear of the body? Are the angled rear down bars required, or what is the alternative? I'm toying with the idea of building this '31 Plymouth for the Drag Week Hot Rod Class. Thanks, Joel [img]http://i.imgur.com/boeexFms.jpg[/img] 31 Plymouth Coupe, 392 Hemi, T56 magnum RS23J71 RS27J77 RP23J71 RO23J71 WM21J8A I don't regret the things I've done. I only regret the things I didn't do. "Wise men talk because they have something to say; fools because they have to say something. ~ Plato"

Re: Roll cage question for a Coupe [Re: Hemi_Joel] #1400416 03/10/13 09:21 PM 03/10/13 09:21 PM
Joined: Nov 2004 Posts: 4,330 Lynchburg, VA Leon441 master
Leon441 master Joined: Nov 2004 Posts: 4,330 Lynchburg, VA	I ran into this with a truck I was doing for a customer. Yes, basic cage has to have the down bars per NHRA. If you go to a funny car spec type cage you do not have to have them. My recommendation is.. You fit the hoop right behind the doors. Build a hooped seat bar that goes behind your seats. Then bend the rear suport bars to curve behind your head and seat down to the seat bar. From the seat bar you can go through the trunk firewall to the frame. You could get creative with this and do just the rear portion of a funny car cage. The NHRA rulebook has some pictures of roadster cages. They are similar in shape to what I have in mind. Just remember the reason for these rear bars is to keep the cage from flipping out of the car with a rollover and hard roof impact. Such as sliding down the track 100 MPH and hitting something stationary. Leon Career best 8.02 @ 169 at 3050# and 10" tires small block power.

Re: Roll cage question for a Coupe [Re: Hemi_Joel] #1400417 03/10/13 09:33 PM 03/10/13 09:33 PM
Joined: Aug 2003 Posts: 43,180 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,180 Bend,OR USA	I love the early Chysler hemi My first real half fast hotrod had a 1955 Chrysler 331 C.I. out of a New Yorker in it. It was in a 1933 Ford Pickup with a three inch chopped top, it had been channeled four inhces over the frame so it was a little tight inside with me and missus in it I didn't realize that the 1931 Plymouth cuope had standard opening doors I was offered a 1934 Dodge cuope for free from a couple who where going through a divorce but I turned it down because I thought it had suicide doors on it like the 1932-34 Plymouth and Fords had I found out later after it was to late that it didn't either Have fun and enjoy that rascal Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: Roll cage question for a Coupe [Re: Cab_Burge] #1400418 03/10/13 11:53 PM 03/10/13 11:53 PM
Joined: Jan 2003 Posts: 3,103 Phila Pa S scatpacktom master
scatpacktom master S Joined: Jan 2003 Posts: 3,103 Phila Pa	How bout you get that Hemi back together first

Re: Roll cage question for a Coupe [Re: Leon441] #1400419 03/11/13 12:12 AM 03/11/13 12:12 AM
Joined: Nov 2008 Posts: 833 MN hemidup super stock
hemidup super stock Joined: Nov 2008 Posts: 833 MN	Quote: I ran into this with a truck I was doing for a customer. Yes, basic cage has to have the down bars per NHRA. If you go to a funny car spec type cage you do not have to have them. My recommendation is.. You fit the hoop right behind the doors. Build a hooped seat bar that goes behind your seats. Then bend the rear suport bars to curve behind your head and seat down to the seat bar. From the seat bar you can go through the trunk firewall to the frame. You could get creative with this and do just the rear portion of a funny car cage. The NHRA rulebook has some pictures of roadster cages. They are similar in shape to what I have in mind. Just remember the reason for these rear bars is to keep the cage from flipping out of the car with a rollover and hard roof impact. Such as sliding down the track 100 MPH and hitting something stationary. Leon The funny thing about NHRA rules is its "all or nothing" attitude. I race my daily driver 2005 Hemi Ram pickup. Comes in a tad over 5200lbs and will run a high 10 on a good day. I planned on installing a 5 pt roll bar so my wife could climb in and out the passenger side with ease, but being a regular cab truck I would need the rear bars to exit out the back window. So then I talk to NHRA and asked them if I kept my e.t's in the 11.80 zone and put in a 4 point cage without rear bars would that be fine? They told me I need to have a funny car cage installed if I didn't want the rear bars. They told me if I showed up at the track with a 4pt roll bar without rear bars, even if my truck ran a 16 flat, they wouldn't allow me make a pass. I questioned them and said a 16 sec vehicle doesn't require a roll bar. They told me it was all or nothing. I told them I'd feel more comfortable with some protection vs none. Sooooo, hopefully my factory seat belts, shoulder strap and factory engineered designed cab will keep me safe if I end up on the roof at a 100mph plus at the beg end. Jerry Williams.

Re: Roll cage question for a Coupe [Re: hemidup] #1400420 03/11/13 09:39 AM 03/11/13 09:39 AM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	Build a funny car style cage [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Roll cage question for a Coupe [Re: B G Racing] #1400421 03/11/13 12:02 PM 03/11/13 12:02 PM
Joined: Jan 2003 Posts: 7,490 Minnesota Hemi_Joel OP master
Hemi_Joel OP master Joined: Jan 2003 Posts: 7,490 Minnesota	Thanks for the replys! THis would be a street car, I am concerned that a funny car cage would make it no fun as a street car. I need something more like a normal roll cage, like what you put in when you hit 9.99 ET. [img]http://i.imgur.com/boeexFms.jpg[/img] 31 Plymouth Coupe, 392 Hemi, T56 magnum RS23J71 RS27J77 RP23J71 RO23J71 WM21J8A I don't regret the things I've done. I only regret the things I didn't do. "Wise men talk because they have something to say; fools because they have to say something. ~ Plato"

Re: Roll cage question for a Coupe [Re: Hemi_Joel] #1400422 03/11/13 01:57 PM 03/11/13 01:57 PM
Joined: Mar 2006 Posts: 9,910 Eighty Four, PA B G Racing master
B G Racing master Joined: Mar 2006 Posts: 9,910 Eighty Four, PA	Quote: Thanks for the replys! THis would be a street car, I am concerned that a funny car cage would make it no fun as a street car. I need something more like a normal roll cage, like what you put in when you hit 9.99 ET. You dont have to build it like a typical Funny car cage,just put the main hoop forward the driver and the cross bar behind the seats and curve the bars back from the main hoop to the cross bar.You must support the cross bar at or near where you attach the two rearward Funny car syle hoops to the frame. [IMG]http://i430.photobucket.com/albums/qq21/ajcasini/max_zpsdppwd9km.jpg[/IMG]

Re: Roll cage question for a Coupe [Re: B G Racing] #1400423 03/13/13 04:56 PM 03/13/13 04:56 PM
Joined: Oct 2008 Posts: 411 Harleysville, PA USA T Tommy D mopar
Tommy D mopar T Joined: Oct 2008 Posts: 411 Harleysville, PA USA	Joel, Have you looked at the NHRA rules for a "Street Roadster"? They are convertible, left hand drive. I can't seem to find my rule book, and it's a few years old at least, but I seem to remember the roll-bar configuration to be less than FC, but more than a typical cage. BTW, I love the coupe. It looks like a nice car, and more of a traditional car. I know you build fast stuff, but will this thing go faster than 10.0??? If not a bar will suffice with no halo or dash-bar. Good luck either way.

Re: Roll cage question for a Coupe [Re: Tommy D] #1400424 03/13/13 10:16 PM 03/13/13 10:16 PM
Joined: Nov 2004 Posts: 4,330 Lynchburg, VA Leon441 master
Leon441 master Joined: Nov 2004 Posts: 4,330 Lynchburg, VA	We are not talking a full funny car cage. Not even a helmet bar. But, the main hoop will be over your head instead of behind it.. This means instead of coming off the level top portion of the hoop with two rear support bars not less than 30 degrees or whatever the book states you do something else. What we are suggesting is bending the seat back brace bar. If you took a yardstick and stood it up against your rear window the seat bar would be just inside the stick. Then you build your rear support brace to curve around the back of your helmet and but into the seat back brace. Then you follow on the other side down to your frame. Then another bar to the rear from the same joint over the seat back brace. This does not constitute a funny car cage but the shape of the bars you use are the same as some used in a funny car cage. Leon Career best 8.02 @ 169 at 3050# and 10" tires small block power.

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