Yup, I would start working on the suspension...my car is going 1.43's now on that same Hoosier drag radial tire with 18-19 psi and repeats like a broken record.

67 Barracuda street car, 408, e85, 1.38 60', 6.44 @105.9 in the 1/8 mile, 10.19 @130.5 in the 1/4...so far....