Starter Problems...

I need some help here! I had some mods done to my c5, to include headers. I've read here at DC that other members have had starter problems due to header heat. The car would not start, it sounded like it would not engage with the flywheel all the way. I checked the flywheel for damage, but it looked fine. I replaced the starter and it worked!! Only lasted me 2.5 days. :surprised Today I went to start it, my battery was low and when it tried to start, it wouldn't. Immediatley after that, when I tried starting it for the second time, it sounded like the starter would just spin freely, without engaging. Is this problem really related to the heat from headers, or was it caused due to dead battery.

Thanx in advance!!