[DavidNJ]

Ummm...Barry should chime in.

You should pick the shop to tune the car. They will either have or have access to a dyno. And should have the various jets, power valves, etc. for the tune. They should also have other tools, including a wide band O2 sensor coupled with the dyno.

Also talk with them about fuel. If you are pulling timing because of detonation, it is sometimes better to start with race gas and remove the detonation issue. Then, when the best settings are found, determine if detonation is an issue.

The other issue is weather dependent. I was just corresponding with someone who builds off-road racing engines, and temperature and altitude changes during a race apparently cause mixture issues that put extreme stresses on an engine. The weather on your tune day could be an issue.

I imagine Cobra owners in Arizona and Colorado have similar problems.