Racer Suspension

SSDiv6 · 05-18-2013, 02:40 PM

[QUOTE=Greenlight;381934]Sammy, the OEM seat belts (~1.8" -2.0" wide) have a minimum break requirement of 6000 lbs. and must retain at least 60% of that strength (3600 lbs.) after long term exposure to radiation (i.e. 20 years), etc. (see FMVSS # 209). For a 220 lb. driver (95% percentile), the 20 year old seat belt can withstand about 17g (maybe a 60 mph crash in a modern car).

The attachments (metal portions) each must withstand at least 2500 lbs. (during a crash the seat belt takes the entire load, while the load is distributed to several hardware points.
Generally speaking, the hardware maintains its strength for more than 20 years. That's why you could pick up the 20 year old car by the seat belt.

Racing seat belts are wider and the racer is exposed to more seat belt area (3" wide, 5 pt.), which is very good in distributing the load to the driver during an impact (maybe a 60g impact). The problem, as I see it, is the SFI spec. indicates that the common material used in "racing" seat belts (Dupont Nylon 6-6) maintains only 60% of its strength after 1 years exposure to radiation, and may only retain 10% of their strength after only 2 years of exposure to the elements. This is what I find unbelievable.

http://www.sfifoundation.com/seatbelt.html

If the SFI spec. required manufacturers to use OEM type material (probably slightly more expensive) the seat belt recertification time could be extended, but the manufacturers would make less $$$ (you always have to follow the $$ trail).QUOTE]

About 10 years ago, I had a discussion with SFI on this subject with enough criteria for extending the expiration requirements for Sportsman racers. I provided actual testing results on seat belts performed under the DOT standards with additional analysis that was extrapolated to expected motorsports and racing forces during a crash and additional studies based on published SAE papers. Guess what? They did not care.

If SFI changed the belt material specifications, it will not increase the cost of the belts. You can procure 660 feet of belt webbing that exceeds both the DOT and SFI requirements for around $150.00. The cost of the belt is in the fabrication and manufacturing.

sammy pizzolato · 05-18-2013, 02:55 PM

so glad to hear the truth about L.S. that is how untrue facts start.i still say that lee was a true racer and would hate to know that he was making a run without belts.RIP LEE. so we can finaly put that story to rest!! thanks to his wife.

boster · 05-18-2013, 08:10 PM

NHRA has the right to confiscate any part on your race car or whole car at the track . When I got suspended at Indy in 2008 they took my crank and I never got it back and it was their right to do so .

I got a year off for that incident and it cost me over 20k when all was said and done

NHRA also has the right to search your truck or trailer when you are on their property and we all agree to it when we get our membership , register for a national event or get a tech card.

If NHRA tech ask's for something you are better off to give it to them and not give them a bunch of BS .

It appears that NHRA tech is not going to tollerate any BS from any racer"s concerning safety or conduct at the track

Sorry to hear that MR Dennis got hit so hard but he is not the first or the last

SS Engine Guy · 05-18-2013, 11:29 PM

And there are racers that have been through tech with the same crank you got tossed for and went through without a second look. Same as all the worked over combustion chambers that went through for 3 years or so until the rule got changed. Lack of consistency is the problem. If a belt is bogus you don't pass tech. End of story.

Carl Weisinger · 05-19-2013, 03:11 AM

The two year seat belt rule is probably the most irritating rule to racers.

Those with big bucks invested in purpose built race cars, huge motor homes,
stacker trailers, spare engines, the best in tools, etc. don't see it as a big
expense. But, the not-so-high-dollar class racer or local bracket guy notices
it when the track tech guy shows him a perfectly good set of belts that have
a tag on them that is over two years old and tells him he needs to purchase
or recertify the belts. The racer many times hears "blah-blah-blah-blah seat
belts, spend more money".

There would have been nothing wrong with having Bob Dennis put a different
set of belts in his car, taking pictures of all the elements of the belts thought to
have a counterfeit S.F.I. tag and allowing Bob to take up the issue of the S.F.I.
tag with whomever he bought them from. Hell, it could have been the only thing wrong with the belts WAS the tag.

PS. I'm predicting Bob Dennis will quit before he pays $5,000 to NHRA over this.

05-18-2013, 02:40 PM	#1
SSDiv6 VIP Member Join Date: Feb 2003 Location: Glendale, Arizona Posts: 3,044 Likes: 712 Liked 1,583 Times in 582 Posts	Re: Racer Suspension [QUOTE=Greenlight;381934]Sammy, the OEM seat belts (~1.8" -2.0" wide) have a minimum break requirement of 6000 lbs. and must retain at least 60% of that strength (3600 lbs.) after long term exposure to radiation (i.e. 20 years), etc. (see FMVSS # 209). For a 220 lb. driver (95% percentile), the 20 year old seat belt can withstand about 17g (maybe a 60 mph crash in a modern car). The attachments (metal portions) each must withstand at least 2500 lbs. (during a crash the seat belt takes the entire load, while the load is distributed to several hardware points. Generally speaking, the hardware maintains its strength for more than 20 years. That's why you could pick up the 20 year old car by the seat belt. Racing seat belts are wider and the racer is exposed to more seat belt area (3" wide, 5 pt.), which is very good in distributing the load to the driver during an impact (maybe a 60g impact). The problem, as I see it, is the SFI spec. indicates that the common material used in "racing" seat belts (Dupont Nylon 6-6) maintains only 60% of its strength after 1 years exposure to radiation, and may only retain 10% of their strength after only 2 years of exposure to the elements. This is what I find unbelievable. http://www.sfifoundation.com/seatbelt.html If the SFI spec. required manufacturers to use OEM type material (probably slightly more expensive) the seat belt recertification time could be extended, but the manufacturers would make less $$$ (you always have to follow the $$ trail).QUOTE] About 10 years ago, I had a discussion with SFI on this subject with enough criteria for extending the expiration requirements for Sportsman racers. I provided actual testing results on seat belts performed under the DOT standards with additional analysis that was extrapolated to expected motorsports and racing forces during a crash and additional studies based on published SAE papers. Guess what? They did not care. If SFI changed the belt material specifications, it will not increase the cost of the belts. You can procure 660 feet of belt webbing that exceeds both the DOT and SFI requirements for around $150.00. The cost of the belt is in the fabrication and manufacturing.

05-18-2013, 02:55 PM	#2
sammy pizzolato Member Join Date: Mar 2011 Location: houma louisiana Posts: 432 Likes: 52 Liked 56 Times in 13 Posts	Re: Racer Suspension so glad to hear the truth about L.S. that is how untrue facts start.i still say that lee was a true racer and would hate to know that he was making a run without belts.RIP LEE. so we can finaly put that story to rest!! thanks to his wife.

05-18-2013, 08:10 PM	#3
boster Senior Member Join Date: Oct 2003 Location: usa Posts: 958 Likes: 0 Liked 0 Times in 0 Posts	Re: Racer Suspension NHRA has the right to confiscate any part on your race car or whole car at the track . When I got suspended at Indy in 2008 they took my crank and I never got it back and it was their right to do so . I got a year off for that incident and it cost me over 20k when all was said and done NHRA also has the right to search your truck or trailer when you are on their property and we all agree to it when we get our membership , register for a national event or get a tech card. If NHRA tech ask's for something you are better off to give it to them and not give them a bunch of BS . It appears that NHRA tech is not going to tollerate any BS from any racer"s concerning safety or conduct at the track Sorry to hear that MR Dennis got hit so hard but he is not the first or the last __________________ Bo Kenney

05-18-2013, 11:29 PM	#4
SS Engine Guy Member Join Date: Sep 2003 Location: usa Posts: 256 Likes: 1 Liked 1 Time in 1 Post	Re: Racer Suspension And there are racers that have been through tech with the same crank you got tossed for and went through without a second look. Same as all the worked over combustion chambers that went through for 3 years or so until the rule got changed. Lack of consistency is the problem. If a belt is bogus you don't pass tech. End of story.

05-19-2013, 03:11 AM	#5
Carl Weisinger Member Join Date: May 2002 Location: Orlando, FL Posts: 98 Likes: 5 Liked 12 Times in 5 Posts	Re: Racer Suspension The two year seat belt rule is probably the most irritating rule to racers. Those with big bucks invested in purpose built race cars, huge motor homes, stacker trailers, spare engines, the best in tools, etc. don't see it as a big expense. But, the not-so-high-dollar class racer or local bracket guy notices it when the track tech guy shows him a perfectly good set of belts that have a tag on them that is over two years old and tells him he needs to purchase or recertify the belts. The racer many times hears "blah-blah-blah-blah seat belts, spend more money". There would have been nothing wrong with having Bob Dennis put a different set of belts in his car, taking pictures of all the elements of the belts thought to have a counterfeit S.F.I. tag and allowing Bob to take up the issue of the S.F.I. tag with whomever he bought them from. Hell, it could have been the only thing wrong with the belts WAS the tag. PS. I'm predicting Bob Dennis will quit before he pays $5,000 to NHRA over this.