I have 50/50 drag shocks on the rear and I want to put the best strut on the front so which should I buy? 70/30's or 90/10's.
What is the difference? How much worse would it be on the street. Any insight?

Thanks

No matter which one you choose your car will handle worse on the street, it just depends on what you want to do with your car. If you drive your car much on the street especially on the highway I would go with the 70/30 struts. Thats what I have on my car and they work well, a good compromise between dragstrip traction and street drivablilty. If you car is race only and you don't care at all how it handles on the street go with the 90/10 struts.

I ran my 87 on the street with the 90/10 struts, 50/50 shocks, no front sway bar, etc all set up for drag only duty. Car still handled very predictably and was still fun to toss into a turn. Being that I've had this car since new and put 200k on the original power train and had replaced the struts and shock a couple times during this time; I'd think I'd know the difference between the characteristics of both packages. Just keep a good set of street radials on it during street use and swap to your race tires for drag use.