I was just wandering how much of a drop in e.t. i could acheive going from 18x9.5 C6 Z06's with 275/35/18 nitto 555's upfront and 285/35/18 nitto drag's outback compared to 15x8 Weld Prostars and 15x4 Weld Alumastars with Mickey Thompson 275/50/15 ET street radials and M.T. Sportsman front runners. Assuming I have traction with both. Thanks.

 

2 to 3 tenths just from reducing the rotating mass.

 

I'm not so sure I would quantify 2-3 full tenths, but there would certainly be a significant improvement not only due to much less rotating mass, but also in the ability to hook up under less than ideal conditions and probably they will help you become more consistent on reaction times as well.

If you do not have a driveshaft loop you will want to install one to provide a little more safety as you hook up better.

What's up with the significant difference between your 1/8 mile ET and 1/4 mile ET? To my mind, if I take the 8.16 and use the standard 1.55 conversion (generic and not vehicle specific) you should be in the 12.6 range... However the mph looks too low for that ET?

Did you get the 1/8 and 1/4 times from different tracks under significantly different weather conditions? Or... Quite possibly... The 18s really hurt your mph and you may actually pick up three tenths... Hmmmm.

 

Sweet thanks

about my times, that was just one pass but ive been having problems with my transmission since i can remember now. The 2-3 shift is extremley delayed, i use to have the rev limiter set to 6200 and every now and then it would bounce the limiter. i just got lucky that pass so, i figure i would pick up a tenth and 1 - 2 mph when its fixed (if i can ever figure out what it is. dang 4L60e). My car has a lot of giddup and go (check the 60') but not to much top end or more like stock. Could be that the tranny doesnt hold very well in third, not sure though.

 

The reason that I said that was that a local buddy just did this swap and weighed all of the components. There was a 100+ pounds difference and that's all rotating mass. Back when I went skinnies on the front it cut 34 pounds and that cut a solid tenth off my ET verified over the whole season.