Unibody roll cage converted to a double frame rail type

[biglady112]

Rather than weld traditional floor plates like a lot of unitized construction cars, I was thinking of going a more promod/double frame rail route on this car. I am thinking of welding to the existing frame rails and building off of that. Like running tubing the length of the existing frame rails and welding it as long and as far as I can. Rather than having a flat belly pan and floor plates that I would build off of.

Does anyone see this being an issue with rules for inspection? I don?t see how it would be less safe than a floor plate design. The idea stems from promod and 3/4 chassis type drag cars.

Below is a picture of what I am starting with. While I am in here replacing the floors, now is my chance as I would like to start work on this project this week.

This car will be a blown J powered car. So no rocket ship.

[trimmers]

Less safe, more safe.  Opinions don't make any difference when you start deviating from the rule book.  I would suggest you submit your proposal to Kiwi Steve prior to showing up with it on the salt.

Jeff in Boise

[Stainless1]

BL... read the rules for the class you are building for... Comp Coupe allows any frame changes... so build your cage within the rules.... 360 protection if you want to pass tech

[javajoe79]

Last car I did, I did what you are describing. The car was intended for altered and or comp coupe so a completely flat floor from firewall to before the rear axle was considered a step pan and was approved by tech. They told me that the bottom of the factory pinch weld along the bottom of the rockers would be considered the bottom plane of the car. I made 2x4 frame rails along the sides with 1-5/8" round tube bridging them front and back and in the middle for seat mounts. The floor was a piece of 1/4" plate to add weight as low as possible. It bolted on for easy enough access and cleaning during a teardown. I did two main hoops and the seat sits under them both and mostly in the back seat.

[biglady112]

This car will be run in an Altered class.

[Rex Schimmer]

Doing a sub frame and building the cage off of it would be my choice. Building the cage and connecting it to a uni-body car would be my last choice. Mainly because it is fairly easy to "connect" a cage to a unibody car and beare rule book legal but not, in my opinion, safe.

Rex

[biglady112]

I spoke with Steve and was given approval for a tubular floor structure.