Full cage weight

Guys, I guess people here would know better than anyone else in the forum about this....

I have a 6 point in my car, is quite thick, it was made when my car was almost 3700lbs, so it had to. (pic attached)

Since I am in a drastic diet on my car, I am thinking in finishing the cage, and instead of having the diagonal across the door from the main loop to the floor (next to my left foot), I'd like to add the halo and go down next to the A-pillar and also do the doors completely.

I was looking at some pics in CC : http://www.corner-carvers.com/forums/showthread.php?t=44946&highlight=documenting+dissection (pic attached) and I found that the roof has a lot of extra meat that can be cut since having a full cage would make that unnecessary. The question is... is it possible to do what I want and losing more weight from the roof than the added tubing.

I will follow NASA rule book. I expect the car to be very close to 3000 lbs at that point, and the CCR says:
1.500” x 0.120” Seamless Alloy (4130), Seamless mild steel (CDS Mechanical), DOM
1.750” x 0.095” Seamless Alloy (4130), Seamless mild steel (CDS Mechanical), DOM

thanks

Id be curious to see what kind of savings you get if you decide to remove the extra metal. I dont think the savings will net you more than the additional weight of the bars you want to add, but any weight off of the top is a good thing. I'm also building a cage in an SN95, so if you have any questions feel free to message me. Personally, I wouldn't do a halo up top. Seem like it could be more work than its worth. I just did 2 bars down on both sides. I posted a thread with my cage if you'd like some ideas.

I was reading:
https://nasa-assets.s3.amazonaws.com/document/document/282/2017.0.pdf ( Page 44) and I think I'd need some sort of bar across the upper side of the windshield.

I'm not sure what you mean? Are you talking about support since you're removing metal from the roof, or a bar across the windshield as in the roll cage? If you're talking about the roll cage, you do need one. You can either do the halo like you suggested, or you can do the 2 separate bars with a bar in between.

Sorry, I was confused, I misread when you said Ï wouldn't do the halo on top, I didn't read the "on top" part, I was just stating that I need a halo (or any of the other options) .

Ah, no worries. Lots of options out there, just depends what suites you best. Also, just throwing this out there. In the NASA CCR it says interior panels and bodywork may be altered to make clearance for a roll cage. That tells me that altering the roof structure is fine. Just make sure you add support if you remove too much.