Oh speak of the devil. My C head swap project for motivation.
If you run tumble port heads on a B head shortblock, you will be rocking a 9:1 compression. Stock correct cobra compression is 9.85:1. Tumbleports are 99-01 heads specifically, and the only years of the 54cc combustion chamber. The 99-01 cobras have different pistons, I've confirmed this physically myself when building my mish mash of a motor. A correctly built C head motor with close to 10:1 compression, heads, ported TB, Maf, injectors, Aluminum flywheel, and a good tune can get pass 300rwhp very easily. It's been done. Especially with good cams it helps greatly. I'm running 99 intake cams which only vary slightly in terms of duration compared to the 98's. Good luck on the build, mines been a slow arduous process but should be going in soon.