I think my tubes are slowing me down
I went from tubeless to tubes and lost almost a tenth

I know my tubes cost me one tenth-but air pressure stays
more stable in the staging lanes on a hot day if your racing
alone. Plus MT recomends tubes.

Strange, my car ran about the same with or without...but it has been a while since I ran tubes...memory might be fading.

It was almost no change for me... but with the tubes
I got a lot more life out of the tires... worth
about 50 passes more(on certain brand slicks)

Without tubes my tires always rubbed. With tubes the tires never rub. The ET difference may have to do with the way a tube will stiffen the sidewall and change the contact patch more than anything.

Depends on weight of car, how fast it runs, how hard it hits the tire. We run Mickey Thompsons and according to their website we were on the boarder to run tubes or not. Harlow's at Norwalk recommended tubes. It adds weight but our 60 ft's dropped .03-.035, e.t. dropped by almost .1 and we haven't lost any mph despite the added weight of the tubes. 60 fts have been more consistent with our car with the tubes. Talk to a qualified tire specialist like Harlow's. Biggest advantage is not having to pump your tires up all the time.

I run new slicks without tubes till the side walls start leaking bad enough to be a pain , then put in the tubes, I don't think there was a tenth difference. Tires do last longer.