J, A few things to consider on this:
Is what dies does your friend have for bending?
The weight difference is pretty substantial, approx. 2.133 lbs per foot for 1 5/8 versus
1.425 lbs per foot for 1 1/2
figuring 85-90 feet of tubing in a cage and you've added about 58-63 lbs, a lot of it up high, not where you want it.
also it sounds silly but bigger tubing will fill up a cockpit pretty quik, meaning less room for you.
Build it right... build it once!!
Also the last cage someone brought me from Jegs was mild steel not D.O.M. it had a seam inside of it, Not legal... he was a drag racer so it didn't matter for SCCA.
Try checking out stockcarsteel.com if you are going to build it yourself, real reasonable prices
YMMV
Chris Leone
318i going STL!!!
E36 ITS underconstruction(sold)
84 944 ITS (sold)
71 240z more than half way there/now GT2 bound!!
ChrisLeonemotorsports.com
Roll cages and fabrication
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