I've learned through the years that this problem is caused by too little clearance between the throttle shaft and bore through the base. The symptom is exactly as you described. Adding more spring pressure to return the throttle makes the car difficult to drive.
There needs to be .003" clearance between the bore and the shaft. Buy a long 8 mm drill. 8 mm is .315", which gives you .003" clearance with the .3125" (5/16") throttle shaft.
I've been through this problem many times, so, believe me, more clearance is the answer.
__________________
BONESTOCK GOATS
'64 GTO Tripower Hardtop (Wife's Car)
'64 GTO Tripower Post Coupe (My Car)
'99 Bonneville SE Sedan
|