I used a set of these and they are noticeably brighter, I mean like a multiple when viewed against my garage door back to back.

https://www.amazon.com/gp/product/B07PFC1Q59/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

I don’t know what flasher my car has, but it still works the same with these bulbs. I’ve read a bunch of posts talking about issues running leds. The first set failed in 00 miles or less and the company sent another one no questions that have held up longer.