• erdero
  • Rookie Driver
  • Offline
  • From: Worcester, MA
  • Registered: 2010-06-22
  • Posts: 14

Topic: Chicago tech questions

We've got a few things we want some, shall we say, more knowledgeable people to look over before we head out to Chicago for our first race, so we can make changes if we have to.

First is the mounting for the belt harnesses.  We found that the angle the belt goes through the seat hole lines up perfectly with where the seat mounts to its bracket, so we're hoping to be able to mount the harness with the same hole and bolt as the seat, like so:

http://i388.photobucket.com/albums/oo327/erdero/24%20Hours%20of%20Lemons/20101017-IMG_0554.jpg

(Sub-question on seat mounting: we're using the OEM seat mounting holes, which are metric.  Grade 8 stuff only comes in standard, but there's metric Class 8.8 which is comparable to Grade 8, so is that also acceptable?)

It's not all the way tight, so the washers in there are hanging down a bit.  But it's grade 8 stuff, so is that legal to do, or do we have to get some plates and go through the floor?

Next is the way we relocated the battery to the back.  We've got a battery box (with a cover) that mounts through the trunk floor with these rods and wing nuts.

http://i388.photobucket.com/albums/oo327/erdero/24%20Hours%20of%20Lemons/IMG_0511.jpg

http://i388.photobucket.com/albums/oo327/erdero/24%20Hours%20of%20Lemons/20101017-IMG_0557.jpg

We're going to add a third rod on one of the sides to stop it from sliding side-to-side, but we're wondering if that's enough, and if it's legal.  We couldn't find anything in the rules about battery relocation aside from using a dedicated battery box, which it is.  It's also kinda rusty on the bottom side, if you didn't notice.

Lastly, we're fairly certain that this is fine but figured there's no harm in asking.  The rules state the metal fire extinguisher mount has to be through-bolted into the car, but is welding okay?

http://i388.photobucket.com/albums/oo327/erdero/24%20Hours%20of%20Lemons/20101017-IMG_0559.jpg

I should point out we're planning on replacing the tire polish with an extinguisher shortly.

Thanks so much for all the help.

Pushing The Nimitz: 1995 Cadillac STS
2010 Chicago: "Most From The Least" Award Winner
http://twitter.com/PushinTheNimitz

erdero's Website

  • From: Wheaton IL
  • Registered: 2009-05-01
  • Posts: 408

Re: Chicago tech questions

The only thing that I think would be a problem is the harness mounting location.  I don't know if it would fail tech, but I wouldn't drive a car that had the seat, and belt mounted at the same position.

You are only entitled to the space you occupy.
  • Registered: 2010-02-14
  • Posts: 577

Re: Chicago tech questions

+1 on the belt/seat anchor.

That bracket will hold a 2.5lb extinguisher? That 1lb polish looks a good fit for that bracket

  • sergio
  • Lemons Staff Stalker
  • Offline
  • Registered: 2009-04-30
  • Posts: 1,185

Re: Chicago tech questions

We used the stock seatbelt lap mounting locations and they made us mount the belts to the floor with a backing plate.

About the battery location. That is way too far to the rear for proper weight distribution. You want the battery over the rear axle. Or as close as you can.

  • From: Wheaton IL
  • Registered: 2009-05-01
  • Posts: 408

Re: Chicago tech questions

Actually you want the battery, and all weight for that matter as close to the yaw center as possible.  That being said, the chances of anybody noticing an extra 30 lbs of weight in ANY position on one of the pieces of shit that show up to these races is zero.

You are only entitled to the space you occupy.
  • JThw8
  • JThw8
  • Administrator
  • Offline
  • From: Mullica Hill, NJ
  • Registered: 2009-06-10
  • Posts: 1,781

Re: Chicago tech questions

+whatever on the seat belt mount.

Also Im pretty sure metric grade 10.(something) is the metric equivalent to grade 8.  Metric 8.8 is the equivalent to grade 5

http://wartburg.misfittoysracing.com
OTTER: "I think that this situation absolutely requires a really futile and stupid gesture be done on somebody's part."
BLUTO: "We're just the guys to do it."

JThw8's Website

  • Registered: 2010-02-14
  • Posts: 577

Re: Chicago tech questions

yup - metric 8.8 equals near enough imperial grade 5

8 Reply by bottlingguy (edited by bottlingguy 2010-10-17 03:51 PM)

  • From: Petaluma, CA
  • Registered: 2010-09-26
  • Posts: 333

Re: Chicago tech questions

I think it is metric 12.9 = our grade 8
My Ace hardware has the best selection of metric bolts (way better than lowes/homedepot).  I did not find any hex head stuff in 12.9 it was all allen wrench stuff

1967 Volvo 122s IOE and C class winner with the transplanted heart of the 1800
1971 Volvo 1800 IOE winner! Killed by a k wall
1984 Volvo 245  Angela Lansbury *sold
Established 2011
  • From: San Diego, CA
  • Registered: 2009-04-30
  • Posts: 1,640

Re: Chicago tech questions

What they said. Our battery and fire extinguisher are mounted the same way yours are and have passed tech several times.

The Homer: Powerful like a gorilla, yet soft and yielding like a Nerf ball.
  • Serj
  • Serj
  • Lemons Staff Stalker
  • Offline
  • From: Cincinnati, OH
  • Registered: 2009-05-02
  • Posts: 1,601

Re: Chicago tech questions

Grade 8 SAE = 10.9 Metric

http://i228.photobucket.com/albums/ee80/JBWood05TJ/Miscellaneous%20Stuff/Metric20vsSAE20strength20grades.gif

  • Registered: 2009-05-01
  • Posts: 526

Re: Chicago tech questions

Seat belts must be mounted to the cage or to the floor.
Mounting them to the seat brackets will cause the driver and seat to go flying in a roll-over situation.
We used some 3"x3" backer plates welded to the floor with grade 8 bolts nuts and washers.
Welding the bracket for the fire extinguisher is perfectly fine.
The battery mounting looks good, double washers is a really good idea, I like that.

Good luck at the race!

Team: V-Ram/Altamont Team: Knights of the Round Track/Reno/Buttonwillow/Thunderhill Team: Death Mobile/Sears 2010/Thunderhill/ChumpCar  Spokane/ MSR Houston/Buttonwillow/Sears. MRolla Project /Reno
http://stickfigureracing.blogspot.com/
  • From: Romeoville, IL
  • Registered: 2009-12-12
  • Posts: 1,117

Re: Chicago tech questions

Ditto on the seat bolt. Don't know what seat you guys have, but most have a threaded square insert that is held on by spot welds. It will tear right out  in a crash. It also transfers the load to the seat rail, which can  cause a failure there unless it was designed from the factory to do so.

The Charnal House Geo MetSHO: Turning less laps than a regular Metro, the hard way!

1969 Subaru 360

Crab Spirits's Website

  • erdero
  • Rookie Driver
  • Offline
  • From: Worcester, MA
  • Registered: 2010-06-22
  • Posts: 14

Re: Chicago tech questions

We'll pick up some 10.9 or 12.9 for the seat mounting.  Thanks.

Here's our seat mounting bracket thing:

http://img203.imageshack.us/img203/2295/20101016img0532.jpg

I assume that since the belts have to mount to the car or the cage, we couldn't just drill an additional hole under the rear seat mounting holes for the seat?  And for the fifth belt, are we going to have to take it off that bracket and go through the floor as well?

Thanks for all the help everyone, it's been great.

Pushing The Nimitz: 1995 Cadillac STS
2010 Chicago: "Most From The Least" Award Winner
http://twitter.com/PushinTheNimitz

erdero's Website

14 Reply by Bender/StickFigureRacing (edited by Bender/StickFigureRacing 2010-10-18 06:28 AM)

  • Registered: 2009-05-01
  • Posts: 526

Re: Chicago tech questions

erdero wrote:

I assume that since the belts have to mount to the car or the cage, we couldn't just drill an additional hole under the rear seat mounting holes for the seat?  And for the fifth belt, are we going to have to take it off that bracket and go through the floor as well?

You can drill a hole directly through the floor under the rear mount seat holes. It must have a backer plate or 3" washer to keep it from tearing through the floor in a collision. You will want to make sure that your belt attachment ring moves freely where it is bolted to the floor. If the belt is pinched or rubs on steel it will not pass. The sub belt can be mounted in the same way if you would like. The way your sub belt is mounted right now, will fail... You cannot attach any part of the seat belt to the seat/brace/or slider.

Sorry I don't have any pics but if you email me offline I can sketch you a diagram that may help.

Team: V-Ram/Altamont Team: Knights of the Round Track/Reno/Buttonwillow/Thunderhill Team: Death Mobile/Sears 2010/Thunderhill/ChumpCar  Spokane/ MSR Houston/Buttonwillow/Sears. MRolla Project /Reno
http://stickfigureracing.blogspot.com/
  • From: Davis, Ca
  • Registered: 2009-04-30
  • Posts: 1,843

Re: Chicago tech questions

You cannot mount the belts to the seat mounting bolts. And the Sub belts should also be mounted to the chassis and not the sliding member the seat is mounted to.

Gosh, my business card says 'Tech Tyrant'
  • From: Wheaton IL
  • Registered: 2009-05-01
  • Posts: 408

Re: Chicago tech questions

Think about this.  If you crash your car, do you want to be attached to the car, or the seat?

You are only entitled to the space you occupy.
  • Registered: 2009-05-01
  • Posts: 526

Re: Chicago tech questions

Trevor57 wrote:

Think about this.  If you crash your car, do you want to be attached to the car, or the seat?

Ha! I am wondering if it would be the first Lemony Ejection seat.:D

Team: V-Ram/Altamont Team: Knights of the Round Track/Reno/Buttonwillow/Thunderhill Team: Death Mobile/Sears 2010/Thunderhill/ChumpCar  Spokane/ MSR Houston/Buttonwillow/Sears. MRolla Project /Reno
http://stickfigureracing.blogspot.com/