Your
oil temp is quite reasonable. I run a smallblock and would consider 100C high for water, but maybe in a big block on a 112 degree day thats not so bad. I have hit that in traffic on hot days here in the northeast.
I did wonder before I got my carb tuned up right about whether heat was a problem for me, so I installed a Holley heatshield, and I wrapped my fuel line from the pump. Yeah, I am using stainless lines all over the place and I agree totally with MobileNuke that that is a source of heat transfer, which is why I wrapped it, along with the fuel log.
I am also wondering (as the others did) if heat really is your problem. Sounds more like a carb adjustment issue. You have a bog, could be an accelerator pump issue, possibly the size of the nozzles being too small and not pumping enough fuel to cover the transition from idle to main circuit. I would do the spacer, maybe the Holley heatshield kit like I got, and wrap up those lines. Then, see if it still happens (my guess is it probably will). Then attack it as a carb adjustment problem.