Weight difference

Is weight difference a big deal in crate racing? I have a crate car that I run in a limited class local we gotta weigh 2400lb but I also run bigger crate races where you can weigh 2300lb. I run top 5-8 and not far off time wise like say pole is 13.2 I'll be 13.5s but my question is is my extra 100-150lb I'm carrying hurting me in the crate races? Car handles to good to be moving/taking lead off for a race here & there but do plan to make it a full time crate soon

The weight does make a difference. 3 tenths difference? Probably not.
The hardest part about weight in a crate (or any steel block) is being able to get enough rear weight in the car without being overall too heavy.