[OneMoreTime]

Does anyone have the information on what NHRA is currently specing for roll cage and chassis tubing..??

I need to make up a steel order for my chassis and I would like to meet spec should I take this car out to the strip..

The car will probably fall into a gas altered classification something like old style BG/A or BG/SR..Might even get stuck into the pro-street class..

Thanks guys..this site has brought back a lot of good memories..

OMT

[willys36@aol.com]

http://www.nhra.com/contacts/tech_faq.html

[OneMoreTime]

I checked that page out and sent off an e-mail for clarification of the spec..they did not say DOM or if the DREW was what they wanted..Does make a difference..

Soon as I hear from those guys I will post that info..

Thanks

OMT

[bracketeer]

If I understand correctly. You are asking about fuel altered class. It no longer exists as it was deemed too dangerous.

The roll cage of any vehicle running 9.99 or quicker, or 135 mph or faster, must also be certified by NHRA every 3 years, and have a serialized sticker affixed prior to participation.

Pro-street roll cage pictured with tubing specs attached or can be found at http://www.nhra.com/contacts/tech_faq.html

[OneMoreTime]

Now forgive me if my memory fails me here..I the early 60's we had four divisions of Nhra..stock, gas, altered and rail.

Gassers could run with a maximum of 10% engine setback as measured from the center of the front axle to the #1 spark plug hole..Altereds were allowed up to 25% engine setback..any more setback that 25% and the car was a rail..

Classifications were by engine displacement/weight break and I canot remember just what the weight breaks were..basically a big block in a lite car went into A..a small block in a lite car went into B and a heavier car would wind up being in C and so on..

There was also blown and ublown divisions and fuel and gas..A blown car had a sub designate of A and if the car ran fuel there was an F in the designation..

So we had the AA/FA blown big block alterd on fuel..and things like BG/A and so forth..that was before brackets and all the new rules..

Any way as far as the tibing order on the mild steel I need to get it figured out if NHRA has to have the DOM tubing (seamless drawn) or the rolled and welded ERW type..big difference in cost between the two and having dealt with tech in the past I do not think it woudl be good to be sent home because I somehow got the wrong tubing specification..

Thanks

OMT

[bracketeer]

I just grabbed that tidbit off the net. My rule book is out in the car. Will check on it. You can also email NHRA at tech@nhra.com

[willys36@aol.com]

The gas classes were unique in that they were the only ones to differentiate supercharged from normally aspirated or injected. Thus A/GS was the top supercharged class while A/G was the equivalent non-supercharged entry. Don't know about the other classes but the weight breaks for gas classes changed up and down several times over the years.

[bracketeer]

I can't remember them all, but there is pro, super pro, sportsman, super gas, super street, prostock, stock eliminator, and comp eliminator.

[OneMoreTime]

I have not kept up with all the variations myself over the years but I do know that keeping up with the rules and staying competitive got to be a real hassle for a lot of fellows..that accounts for a lot of the former race cars setting in someones barn somewhere..

OMT

[OneMoreTime]

Well guys I am going with the HREW tube..that is the stuff that has a welded seam..Apparently it is legal as Art Morrison is using it for his cage kits in the 0.134 wall thickness..

Since this is more for me than for anyone else thsi is the way to go..the HREW is much cheaper as well than the DOM and 4130..well bottomless checkbok is needed for that..

Thanks for the Input guys..

OMT

[BillyShope]

Originally posted by willys36@aol.com
... Don't know about the other classes but the weight breaks for gas classes changed up and down several times over the years.

And the altered classes. The original Ramchargers will go to their graves resenting the NHRA's change in the weight break for C/A after the car was barred from competition by the crankshaft height rule. This was interpreted as a rather obvious NHRA move to allow Chevy powered cars to regain the records that had been set with the hemi.

[OneMoreTime]

Now there is a subject that can keep us going for a long while..arcane little rules that can be used to DQ someone..

having to completely rebuild a car from season to season to stay competitive and somewhere near to being in the rule book..

All that sort of thing has done more damge to racing than any other thing that I can think of..

OMT

[willys36@aol.com]

Originally posted by BillyShope
And the altered classes. The original Ramchargers will go to their graves resenting the NHRA's change in the weight break for C/A after the car was barred from competition by the crankshaft height rule. This was interpreted as a rather obvious NHRA move to allow Chevy powered cars to regain the records that had been set with the hemi.

Yes, they messed with the rules a lot to nuke individual racers. Like when Ronnie Nunes knocked an unbelievable 1/2 second off the B/GS record in '65 with his 327" Olds powered '41 Willys @ 9.94 sec. That's equivalent to Bob Beamon's 29'7" long jump, Maury Wills' 104 stolen bases, Roger Maris' non-steroid 61 homers, etc., - unbelievable! No one could come close enough to that record to qualify for the finals so they threw out his record and artificially set it back to 10.44.

[OneMoreTime]

Nhra returend my message and it appears that one can use either HREW or DOM even 4130 if one desires..but then the rule requires 0.120 wall 1 3/4 for roll bar..and 0.120 wall 15/8 for roll cage..

Does not make a lot of sense to me as those are three way different specs for the same tube in the same roll cage....but oh well..Does not have to make sense to me..

OMT

[willowbilly3]

Originally Posted by willys36@aol.com

Yes, they messed with the rules a lot to nuke individual racers. Like when Ronnie Nunes knocked an unbelievable 1/2 second off the B/GS record in '65 with his 327" Olds powered '41 Willys @ 9.94 sec. That's equivalent to Bob Beamon's 29'7" long jump, Maury Wills' 104 stolen bases, Roger Maris' non-steroid 61 homers, etc., - unbelievable! No one could come close enough to that record to qualify for the finals so they threw out his record and artificially set it back to 10.44.

Is it just me or do those sort of rule changes tend to favor Chevys? It seems like in Nascar they do. If Ford goes out and wind a couple races 1-2-3 then Nascar takes some spoiler away or something to slow them down. Chevy can win 1-2-3 all year and they don't jump on them.