Really? Thats a lot. Personally seen a BBC that went from 10:1 to 13:1 with nothing else changed and it gain only 40hp. Now he has to run race gas. Maybe there's more gain going from 8:1 to 11:1 (same 3pt increase)?
I have nothing personally to back this up but from what I have read it seems the gains diminish as the compression gets higher. Much more to be gained from going from 8:1 to 10:1 than there is from 12:1 to 14:1.
The only downside to W2s in my opinion is that they are Iron. My Dad and I built a W2 headed 416 for drag week. We had to lower the compression some to know we would be safe on pump gas and its HEAVY. It took three full turns on the torsion bars to support the R1 W2 headed 416 over my aluminum headed 360.
