thinking about buying the blox type b cams and dual valve springs combo kit and come titanium retainers, my question is do i have to upgrade my valves too or will my stock b16a valves work fine?

 

You should not upgrade valves unless you are going for oversized valves and a full port job. Some people will argue to buy Stainless steel or even upgrade to Type-R valves but in all honesty you will pay big money for no advantage.
For those who are reading the Factory type-R valves (ITR/CTR) have a tapered design that some say will increase flow. The real reason was to cut back on the valvetrain weight for better high rpm's. This actually had no benefit and was nothing more than over-engineering as proven by numerous engine dynos done by Endyn.
For everyday application or race, the factory valves are best. A valve job can be a good idea so long as it is preformed by an actual reputable shop.
Now the factory valves can fail but only if you have a bad tune or high mileage. Also there are the stainless steel flat faced valves that increase compression but it is not much.

 

Agreed no point in getting new valves, unless your stock ones do not seat correctly or a burnt.

 

It makes sense to replace the valves for sake of durability.