No I dont have a specific recommendation but as you know it'd take something stiffer than what is in the chart then work with when it maxes out. point X is the most important (when it starts). it's gonna take alot of trial and error and grinding the tips of the weights to fine tune is an option in addition to springs. the MP/transdapt/mr gasket spring kits only have (1) pair of springs each & they are very light. EDIT I would call Don at FBO & find out if any of the springs in his (3) piece spring kit with the OE light spring or a combo of his springs will give you a point X at 1200 or above for your needs. MORE EDIT I ain't tried this yet (just thinking out loud) but I'm thinking a person could drill the weights & melt in lead to increase the rate. SB & BB weights are different & the SB ones look like a comma at the beginning of a sentence and BB, the ones at the end of a sentence. MORE EDIT the heavy OE spring with the elongated loop on one end, a person could cut/rebend that loop to make a "regular" spring out of it, it is heavy tho