reading the regulations it calls for 1 3/4 OD x .118 mild steel tubing and also the .083" 4130 chromoly but i have access to a unlimited supply of I have 1 7/8 osd 1 1/2 isd sch10 would that be ok? Thanks for any help

 

Has to be Dom tubing.

 

Ok thanks guess I did not read that part.. That will have to be ordered

 

do it right the first time and go with chromoly. you wont be disappointed in the long run

 

Ya I was debating on mild steel or chromoly ..

 

I have this concern also, why Chromoly over mild steal? what are the benefits, advantages and ease of installation, weight etc. ?

 

I have heard it's harder to weld, but I didn't experience anything that made it harder necessarily. But I was welding it on my bench with a super easy position, ect. But the weight is much less with Chromoly.

 

Lighter and more rigid. Drag racers prefer this as it adds less weight and also (when done properly) provides a more rigid chassis structure overall. This is good for torsional stiffness but NOT as ideal for impact attenuation (ability to absorb impact during a crash).
Chromoly can be downright dangerous when not fabricated and welded properly. Gaps must be done right, joints chamfered, and of course the weld makes all the difference.
Chromoly being more rigid does make it more prone to cracking and breaking under load or impact. During a crash it is so rigid that bars deform less which means they will transfer more energy to the driver during an impact.
Mild steel is heavier to a degree but it is also more forgiving during fabrication. It also has a longer shelf life in a car based on it's flexibility. It is cheaper and well, it BENDS. Most people tend to think that is not a good thing, but in a wreck it is the very best thing. Look at ALL OEM car manufacturers safety tests and provisions. They all use crumple zones and those contrivances are designed to absorb impact. They slow the vehicle speed and G forces before they reach the driver. Mild steel acts in a similar manner and is why most ROAD RACERS use mild steel.
This does not mean either of them are bad choices, you just have to choose what is right for you. When I weigh the pro's and con's the ONLY thing I think Chromoly has over mild steel is weight savings, and when I factor in the cost for that savings and consider mild steel being the potentially safer material I choose mild steel.
That is my $1.00 worth of info. on the subject.

 

and that is the answer I am looking for, I don't care about weight reduction, I want something that will protect me during a rollover, and does not cost an arm and leg, 30lbs less weight is not worth 100% more the cost, I weigh 240lbs as a driver. a mild steel cage weighs 130lbs I don't think thats too much weight. I use a mild steel in my EG last year.

I am interested in the rear down bars requirements, I am building a del sol and I am wondering if I am required to go to the trunk with the rear bars.

 

beings steel cages can be mig welded and chromoly has to be tig welded, some will say its harder to weld if they do not know how to tig weld.

in our shop, its 50/50 chromoly to steel cages from what it seems like

NASCAR uses DOM due to what hduced said about chromoly being more ridgid and prone to cracking. Hence why all the nitro cars cannot paint/powdercoat their chassis in order to check for cracks periodically.

 

Thanks for everybody's help I see I'm reading a lot of great information.. one more question does the main hoop have to be one piece? or can it be welded sections? Ty

 

One piece

 

Ok thanks again I'm sure I'll be posting more questions throughout my build

 

From what I can remember, please don't quote me... But with del sols you can have a bend in the rear down bars to accommodate them going into the trunk...

Look at post number 12 on this thread... and you will see what I'm talking about... maybe talk to this guy and ask about rules with them he seems to know what the heck hes doing...

https://honda-tech.com/forums/drag-racing-36/something-little-different-62mm-del-sol-build-2013-a-3115397/

 

steel cage here. ill just try and loss the extra weight somewhere else. I think I have already lost enough though.

 

yeah I think I'm going to go with a steel cage I mean it's already a VX with no power steering ac manual rack the dash is completely gutted and so is the back so its pretty light