Help! I Don't Speak Cam!

With street use, I'll assume you you mean a lot of cruising and roaming around in the hills, NOT street racing.... you will get better results if you define 'street use' more. Can you make your actual use plans clearer that just 'street use'?

In that case, you would like to go with a cam of not too much duration. If you go too short with a true 10.5 CR, you will end up with detonation problems. So how short you can go depends on if your compression ratio really is going to be 10.5:1. But such pistons as advertised for the 273 typically end up quite a bit lower in actual compression ratio.

So, to really answer your question, I would like to see what brand pistons you are planning on, and all details of what you plan to do around the combustion chamber. And the planned rear gear ratio does have a bearing on it....probably a 3.23 or 3.55 in that axle.