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Land Shark!
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I posted this in the coupe forum a while ago, copied from the NHRA rule book. This is good down to 10.99, below that all hell breaks loose as far as safety equipment...

General regulations for Roll Bar:

All roll bars must be within 6 inches of the rear or side of the drivers head, extend in height at least 3 inches above the drivers helmet and be at least as wide as the drivers shoulders or within 1 inch of the drivers door. Roll bar must be adequately supported or cross braced to prevent forward or lateral collapse. Rear braces must be of same diameter and thickness as the roll bar and intersect with the roll bar at a point not more than 5 inches from the top of the roll bar. Sidebar must be included on drivers side and must pass the driver at a point midway between the shoulder and elbow. Swing-out sidebar permitted. All roll bars must have a cross bar for seat bracing and as the shoulder harness attachment point. Cross bar must be installed no more than 4 inches below, and not above, the drivers shoulders or to side bar. All vehicles with OEM frame (does this apply to us????) must have roll bar welded or bolted to frame.
 

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I build roll bars/cages. If you can show me some good pics of a spec racer bar with the body off, I can tell you if it's legal or not.
 

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Ok, that pic def helps. Here's my thoughts...

The first issue is tubing. How thick is the roll bar tubing on the spec racer? To be NHRA legal to 10.00 you need a minimun of a 5 point roll bar (the pass side is not actually required), and it has to be 1 3/4 tubing. If it's smaller (1 1/2, 1 5/8) it's NOT legal.

Now back to the design. As mentioned, you just need a 5 point to be legal to 10.00. Nobody does just a 5, so we'll just say a 6 point. The side bars must pass the driver between the shoulder and elbow. Now many cars don't exactly pass there, it's up to the tech inspector to make a decision. Basically the idea of the side bar is will it keep you in the car if the door opens during a crash. The main hoop technicially needs to be at least 3 inches above the drivers head, but in reality most cars with roofs don't allow that. On the main hoop, the tech guy just wants to see that the hoop is higher then the helmet with the driver in seating position. The rear bars kind of concern me a bit, where they attach to the main hoop. You can go down 6 inches from the top, and it's hard to tell from the pic how far down it is. As for how the bar is attached to the frame, there really should be no issues there, since the bar is directly attached to the frame at every point.

My suggestion is this.. Make sure the main hoop is higher then your head when you sit in the car. Lower the seat if you have to. Make sure the side bars look like the will keep you in the car. Since this car has no roof (or any structural body for that matter), the tech inspector is going to pay special attention to this roll bar. It's the only thing protecting you if you flip. I also strongly suggest bringing the picture with you that Larry posted above. If the tech guy has any doubts or can't see how the bar is attached, that will show him that the roll bar is part of the frame assy.

Now keep in mind, that everything I've said is for full bodied cars and unibody cars. The FFR is neither of them. It technically falls into the roadster/altered catagory, so if you get a tech guy that REALLY is by the book, forget about passing tech. To be truely 100% legal, this kind of car need an NHRA roadster cage.

As for the rest of the car being NHRA legal, that's up to you.


[ July 19, 2004, 02:32 PM: Message edited by: Power Surge ]
 

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Quick-1 has a neat bolt in cage and he runs under 10 sec. I bet a search would turn it up.
 

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Hope this works........


Don't know why that didn't work, but the picture is in Quik 1's gallery.

[ July 19, 2004, 02:47 PM: Message edited by: Mike Noyes ]
 

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I just checked out that picture of his setup. It's definitely NOT NHRA legal BUT, from a safety standpoint, it's a smart design. I can see tech guys at local tracks letting that go, because logically it would keep him safe. He'd just not likely get away with it at a national event.
 

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Steve Pass did a 10.4 quarter here in a SB Ford:


Not seen him posting lately...maybe the roll bar failed techs?

His setup:
1. FFR with a 4 link;
2. 8.8 rear end;
3. with Autowelds;
4. spring rate at 250# in the rear;
5. Tires are 28X10 ET Drag slicks;
6. Tremec TKO II transmission;
7. 3.55 rear end ratio
================================================
QUIK 1 Roll Bar:

Brian's removable roll bar

Presto, and back to this:

1. FFR MK 1 with a 4 link
2. 9" Moser rear end
3. adjustable uppers w/ 2'- pinion angle
4. spring rate at 200# in the rear
5. Tires are 26X10 ET Drag slicks
6. Tremec TKO II transmission w mid/shift kit
7. 4.10's Detroit locker 31 spline Moser axles

Best times so far:
1/4 = 10.74 @123
1/8 = 6.75 @ 101
60' = 1.45 leaving @6500 rpm

Goal for 2003 is 10.50's "

Brian aka Qwik1
 
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