The V8 Owners Forum -

Slapper bars are easy to make to bolt under leaf springs. I just had to buy slightly longer U bolts
This is a vid from back in the day. But you can see the slapper bar on the passenger side doing its stuff.

That's impressive launching hard like that !!

If my 60 foot is around 2.5secs, if I got that down to 1.5secs does that make much difference on et and trap speed?