FYI. Typically most drag cars make 64% of your 1/4 mile ET in the first 1/8 mile (660 ft).
Therefore, you just multiply your 1/4 mile ET by .64 and that will give you the approximate 1/8 mile ET.
For example; 10.00 1/4 mile car (10.00 x .64) would be around 6.4 in the 1/8 mile.
WD