1997lt2ss

my camaro (1997 camaro ss) cranks between 10-20 seconds on first start now if you turn the car of right after it fires up it starts right away at first i thought the cranking issue was charging related so i replaced the alternator starter with a lt4 starter and a red top optima battery still the same takes along time to start first time then starts fine unless you let it sit say 8 hours at work then the issue starts again
some background on the car its a 1997 camaro ss with a lt4 hot cam 6 speed 73,000 miles on the clock always run 93 fuel never used any fuel treatment i have noticed the temp sender on the drivers head i cracked from the header install ( but to my understanding all that does is send a temp reading to the guage on the cluster so i cant see that being a issue,after the car does start it idles at 900-950
tryed to include as much info as i could think would be helpful if i missed something please let me know and i will post the info
thanks for any help