Radials don't work well on stick cars. I tried radials on the car in my in my sig to match the radial fronts. It either spun, or hooked and hopped BAD!
Couldn't get out of the 12's all over the place, et wise.
Put the bias on, and never looked back. Last time out, all runs were within a tenth. (11.39, 11.40 and another run in the 11.40's, can't remember off the top of my head.
I don't drive it enough on the street to see any problem with radial/bias mix. I'm more worried about getting caught in the rain, they're basically treadless.
'87, 105,000 mile stk short, SN89 Paxton 5 LBS, X303 Hds, E303, Cobra Int, 70 mm TB, 30# injrs, 1 5/8 full leng, no cats, 2 1/2 w/dumps, A5, 3.73, ET R's, Frnt Drag Eibach sprngs, Baseline Relocated upprs, HPM lwr arms, stk rear sprngs 1 coil cut, adj. struts shocks, 3150 w/dr. 1.60 11.39 118.