with a 6inch lift in my 91 fullsize blazer will the angle of the driveshaft with the lift affect it at all and also is there a place that sells more heavy duty diveshafts?

 

i ran 6inch lifts for many years on fullsize trucks... i dont really know what you mean by affect it but it does change the angle a bit.. the rear blocks or springs should have wedges that will tip the axle up. i ran 38s with a 6inch lift on fullsize trucks for like 9 years and never broke a u joint. probably cause it was just a stock engine