We fd owners are familiar with this issue. The solution that we use is the hks twin power.
HKS Twin Power DLI Ignition System Harness SR20DET
http://www.rhdjapan.com/hks-twin-pow...-12353?nflag=1
We get spark blow out at around 350whp. This is the solution to 550+. This is on the fd reliability mod list and most people modifying fd's run these as a standard. Probably translates to sr20's too. But the communities are VERY different, and these units are kinda pricey. AEM makes one too but i'm not confident in their ability to make quality electronics.