|
07-31-2013, 03:56 PM
|
|
Senior Member
|
|
Join Date: May 2013
Location: Folsom, CA
Posts: 2,422
Thanks: 45
Thanked 35 Times in 26 Posts
|
|
Quote:
Originally Posted by Chassisworks
Ron,
Our theory with offering the cage in 1-3/4 x .120 wall DOM is that is the requirement for most national road race organizations. If I have heard Chris say this once, it's been 50 times (and I'll paraphrase so I don't get banned for swearing): 'Making these cars handle like race cars without adding adequate protection is stupid, anyone who thinks that they and the car will survive a rollover is on dope.'
Or something to that effect. This is why our gStreet Full Frame comes STANDARD with a six-point, weld-in roll bar.
I'll leave it up to you guys to hash out diameters of tubing. I don't pretend to be a super smart engineer; I just work for one. He let's me touch the computer because I tend to be less abrasive.
|
I've known Chris for over 30 years.
MAN ... did you clean his statement up.
You probably needed industrial strength cleaner & a clean suit ... to get it that "polite."
.
__________________
Ron Sutton Race Technology
|
07-31-2013, 08:23 PM
|
|
Senior Member
|
|
Join Date: Dec 2012
Location: Pacific NW
Posts: 484
Thanks: 0
Thanked 0 Times in 0 Posts
|
|
This is great discussion here... thank you Ron, and the others for sharing your views on safety, and for throwing out practical solutions on how a pro touring type car can be made safer.
I am the guy that has built a pro touring car with high horsepower, and loves to get out on a fast road course and push the car to it's limits (130 mph on the sweeping curves of road-course america )... like lots of the guys on here. After reading this thread I have made the decision to improve the safety of my car.
Right now my car is set up with a welded in DSE 4-point roll bar and G-Force 5 point safety harnesses... I plan to modify my roll bar per the design shown here. I will use 1-5/8" chromoly tubing with welded connections.
Not only will I improve safety... but the chassis will be stiffer... win win.
__________________
" If you wait, all that happens is you get older"
Mario Andretti
69 Camaro-Nutter Racing Engines/427CI LS2 sleeved/LS7 CNC ported heads/Custom cam/T&D 1.8 rockers/Manley crank/Manley H-beam rods/Weisco pistons/NRC Pro Series dry sump/Kooks/NA,92 octane,11.5:1- 672HP @ 6,900RPM, 566TQ @ 5,500RPM
Build Thread- http://ls1tech.com/forums/generation...ine-build.html
|
07-31-2013, 08:39 PM
|
|
Senior Member
|
|
Join Date: May 2013
Location: Folsom, CA
Posts: 2,422
Thanks: 45
Thanked 35 Times in 26 Posts
|
|
Quote:
Originally Posted by DaleTx
This is great discussion here... thank you Ron, and the others for sharing your views on safety, and for throwing out practical solutions on how a pro touring type car can be made safer.
I am the guy that has built a pro touring car with high horsepower, and loves to get out on a fast road course and push the car to it's limits (130 mph on the sweeping curves of road-course america )... like lots of the guys on here. After reading this thread I have made the decision to improve the safety of my car.
Right now my car is set up with a welded in DSE 4-point roll bar and G-Force 5 point safety harnesses... I plan to modify my roll bar per the design shown here. I will use 1-5/8" chromoly tubing with welded connections.
Not only will I improve safety... but the chassis will be stiffer... win win.
|
Yes it will. The more rigid chassis structure makes the car faster, more responsive & tunable.
__________________
Ron Sutton Race Technology
|
07-31-2013, 09:51 PM
|
|
Lateral-g Supporting Member
|
|
Join Date: Apr 2012
Location: Livermore
Posts: 2,445
Thanks: 111
Thanked 83 Times in 61 Posts
|
|
Ron, regarding that "common" drawing from two posts above, what is the point of diminishing return regarding lowering the triangulation from the door entry?
in other words, how low can it go, mostly you want the safety first, but entry dynamics come into play from the pro-touring vs racing side. I've seen alot of them run parallel to the running boards, which only help, i believe, in torsional rigidity, but not rollover protection. Is that part of the cage designed to help keep the main hoop from crushing?
I noticed its at the height of the harness bar, how much lower can it go while still retaining most of its integrity, while still being able to climb in ok (think wifey). 90% of my car is built for street, but track 10% of the time, i dont want to sacrifice safety, but ????? how low can it go?
thanx, Mike
Last edited by glassman; 07-31-2013 at 09:52 PM.
Reason: forgot me name
|
07-31-2013, 11:07 PM
|
|
Moderator
|
|
Join Date: Dec 2010
Location: Pacific Northwet
Posts: 7,896
Thanks: 33
Thanked 87 Times in 36 Posts
|
|
Quote:
Originally Posted by Ron Sutton
|
That would be "PC Gap Spray" around here.
|
08-01-2013, 01:10 AM
|
|
Senior Member
|
|
Join Date: May 2013
Location: Folsom, CA
Posts: 2,422
Thanks: 45
Thanked 35 Times in 26 Posts
|
|
Hey Mike,
Thanks for putting your name in the post. I always feel weird referring to someone's "street name".
Quote:
Originally Posted by glassman
Ron, regarding that "common" drawing from two posts above, what is the point of diminishing return regarding lowering the triangulation from the door entry?
in other words, how low can it go, mostly you want the safety first, but entry dynamics come into play from the pro-touring vs racing side. I've seen alot of them run parallel to the running boards, which only help, i believe, in torsional rigidity, but not rollover protection. Is that part of the cage designed to help keep the main hoop from crushing?
I noticed its at the height of the harness bar, how much lower can it go while still retaining most of its integrity, while still being able to climb in ok (think wifey). 90% of my car is built for street, but track 10% of the time, i dont want to sacrifice safety, but ????? how low can it go?
thanx, Mike
|
Well ... what it was designed for originally ... could be open to interpretation. I can only share with you my experience & points of view from that experience.
For safety purposes, it does two key things, by priority:
1. It is to prevent mean things from coming into the car & killing you. Unfortunately, I know from first hand experience where guys died from side impacts with trees, telephone poles, ends of concrete barriers, other cars, etc. So it needs to come up high enough to protect the driver & passenger's bodies from impacts.
Look at the illustration I attached here ... from the NHRA rule book ... and see where the driver is in relation to that door bar. The door bar acts as a barrier between the driver & passenger's bodies and "stuff." If that door bar is 1-3/4" x .095" Chromoly ... it can take a hard hit & bend a few inches. In faster, harder side impacts .. the object may very well come in much farther, but the tube will help slow the object. This can mean the difference between broken bones & death.
So, to answer your question about how high it needs to be, varies with your seat mounting. The key is to make sure the Chromoly tube is a barrier for the driver & passenger's torsos when they are in the seat. I like to make sure it is protecting the majority of their body, as shown in the illustration. This varies with seat height, angle & placement ... and is usually lower than this drawing.
2. It is the only thing preventing the roll bar from folding in the middle in a hard flip or roll over. It turns a triangle into a double triangle, sort of like making it a truss.
But I don't set the height for this role. I set as outlined in #1.
__________________
Ron Sutton Race Technology
|
08-01-2013, 08:40 PM
|
|
Lateral-g Supporting Member
|
|
Join Date: Apr 2012
Location: Livermore
Posts: 2,445
Thanks: 111
Thanked 83 Times in 61 Posts
|
|
yep makes total sense. its almost as if i will be "tailoring" it to fit. Which, i guess, gave birth to the word "custom"....as one size does not fit all...this is up next on the car once the tuning and clutch are sorted out. I have a "hoop" from Alston, but need the rest of the components.....
|
08-05-2013, 08:47 AM
|
|
Senior Member
|
|
Join Date: May 2013
Location: Folsom, CA
Posts: 2,422
Thanks: 45
Thanked 35 Times in 26 Posts
|
|
Quote:
Originally Posted by glassman
yep makes total sense. its almost as if i will be "tailoring" it to fit. Which, i guess, gave birth to the word "custom"....as one size does not fit all...this is up next on the car once the tuning and clutch are sorted out. I have a "hoop" from Alston, but need the rest of the components.....
|
When you say it's from "Alston" ... is that Chris Alston's Chassisworks or the old Alston Race Car Engineering brand that was bought out when Chris' brother Tom's company went defunct long ago?
I ask, because Chris Alston Chassisworks builds the best roll bars. The use a higher grade of steel, because Chris understands steel. And the roll bars & cages fit tighter to the body which provides more room for people to move around... especially the driver who can get quite busy in the cockpit.
__________________
Ron Sutton Race Technology
|
08-05-2013, 01:09 PM
|
Supporting Vendor
|
|
Join Date: Apr 2012
Location: Sacramento
Posts: 312
Thanks: 0
Thanked 0 Times in 0 Posts
|
|
Regarding the placement of the main hoop: Per NHRA rules the main hoop of a roll BAR must be within 6" of the helmet, vertically and horizontally, but it does NOT have to be that close when you have a roll CAGE. I do not know if this is the case with any other sanctioning bodies (NASA, SCCA, et al.) but thought it worth a mention.
Quote:
Originally Posted by Ron Sutton
When you say it's from "Alston" ... is that Chris Alston's Chassisworks or the old Alston Race Car Engineering brand that was bought out when Chris' brother Tom's company went defunct long ago?
I ask, because Chris Alston Chassisworks builds the best roll bars. The use a higher grade of steel, because Chris understands steel. And the roll bars & cages fit tighter to the body which provides more room for people to move around... especially the driver who can get quite busy in the cockpit.
|
Thanks Ron! There are definitely differences. The old Alston name is still around as 'Alston Race Cars,' mostly selling parts Chris designed in the '70s. Interestingly, it was sold last year and purchased by one of our competitors.
|
08-05-2013, 02:44 PM
|
|
Moderator
|
|
Join Date: Dec 2010
Location: Pacific Northwet
Posts: 7,896
Thanks: 33
Thanked 87 Times in 36 Posts
|
|
Quote:
Originally Posted by Chassisworks
Interestingly, it was sold last year and purchased by one of our competitors.
|
Hope that doesn't create any unnecessary brand maintenance.
|
Thread Tools |
|
Display Modes |
Linear Mode
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -5. The time now is 07:02 PM.
|