Todd,

While I don't have an OS48 in my Stearman I do have the 52. I can say the 52 does fly the plane nicely. There is plenty of power for aerobatics and most times it's flying way too fast for scale speed even at 3/4 throttle. It's nice to have the extra power to pull you through the manuevers.

I suspect with a 48 the Stearman will fly in a very scale-like manner. Takeoffs will not be a problem and you may need to enter a shallow dive for loops but this would be like the real thing. If you are desparate for more power then you can up the nitro to 30% (I've been doing this with almost all my 4 strokes now with no ill effects) providing you increase the prop diameter a bit and reduce the pitch. You don't need speed to fly the plane, just power and a lower pitch will give you that.

IIRC OS dropped the 48 to produce the 52 and I can't see there would be a whole lot of difference between the two other than a few HP points.

All in all the 52 is more than enough engine to fly the Stearman so the 48 should work well for you.

hth

Jeff

you can see my Stearman build and flying video at my website: http://www.geocities.com/jbrundt2/N2S-1.html