11 to 1 - too much on CA 91 pump gas?

[Dominik]

Again, I can only advise to see a dyno. You will see a dramatic power loss when timing is too advanced. Retard 3 deg from best value at the dyno to accommodate real live conditions (like underhood temp)

More critical is full throttle operation at medium engine speed where you have to keep an eye on your advance curve coming in too quickly. However, if this pinging is very short you can get away with it, but it is NOT recommended!
Typical example: your Winnebago going uphill at 2000rpm. Lift throttle or shift down.

And do not forget at idle speed where retarded timing can cause your headers to glow red hot in 2 minutes.

Don't fool around with this. One 1/4 mile run with wrong timing or one long back straight can cost you an engine.

[blykins]

Unfortunately, it's very hard to drive a dyno. The only real amount of tuning that you can do is for WOT and that includes jetting, total timing, etc., trying to find the most horsepower.

That same combination may have a horrible lag or dead spot on the street when you're out driving.

If you can get it close on the dyno, then the best scenario is to get it out and drive it, then tune from there.

One more important fact here is that timing will most likely not be the same from the dyno to the car anyway. MSD boxes can vary up to 5-6° and just because you had the timing set on the dyno doesn't mean that it will be the exact same in the car. This happens all the time to engines that I dyno and send out to the customer. I always advise the customers to recheck the timing once it's in the vehicle.

There are also airflow differences, where on the dyno, air is funneled in through a big hose. In the car, airflow gets in through several different ways and will not be the same volume of flow.