351c timing issue

[Kwiksilver]

The 351 cleveland in my shop truck is coming together finally but I have an issue... I put a bracket master II cam in it with big valve closed chamber heads, full mallory ignition, mighty demon carb and switched from a c6 to a top loader 4speed. The problem is... with the c6 and the 3000-ish stall It didn't matter that I didn't have the vacuum advance cause of the stall, but, now I have the 4 speed and it pings pretty bad at low rpm's when I have the timing at 36-38 where it like to be. Is there a box that will retard the timing before the rpm's get up that will sort of simulate what the vacuum advance does when the vacuum drops? in other words... what do you do when you run a 4speed with only the springs in the dist.? the springs in the dist kick in at about 3k rpm's now