Unported head quickness?

I’ll add one to the list.

Nothing trick at all.....

68 Satellite(those are A bodies..... right?)
3580 lbs, 4.10’s, 29.5” slicks, SS springs, lil red converter with weight removed
Re-ringed 68 440 short block
346 heads with NAPA store valve job
Crower springs and retainers
Crower 271hdp cam
Stock rockers, shafts, and pushrods
Regular Performer, Holley 780VS
1-3/4 headers
Shifted at 5000

12.40’s@110 like clock work

Swapped to an underdrive pulley, cut the oil pressure relief spring down to get the pressure down from about 100 to 55psi...... and the biggie was to swap the Performer to an original Torker.
12-teens at 111-112, best of 12.12.

That would have been in 90/91.