Numbers. This discussion is sorely in need of some hard data on several counts. You can only do the math if you have the numbers! Do we have ANY of these measurements we need: Cylinder head volume; Deck height & Head gasket thickness (what would be a squish band, if not discussing a Hemi as opposed to a flat-top cylinder design). Once given these data, and then the bore size is chosen, the compression ratio can be calculated.
Being a Hemi chamber, the easiest way I know to measure the volume would be to measure by liquid displacement: Fill the head's chamber level with oil, then measure the volume of oil removed from the chamber. A reasonably accurate measurement can be achived by drawing the fluid out with a very large syringe like a veteranarian uses on large animals:
I took a picture of the biggest syringe I have, but I don't think it would be big enough to measure the Savage's cylinder head chamber volume. Using an estimated squish area, and compression ratio, I *guesstimate* that we are looking at a total chamber size in the area of 45cc (head chamber area + deck squish area + gasket thickness area). Maybe a 35cc syringe would be big enough to measure head volume, since much of my estimated 45cc total is from the squish and gasket areas. The volume of any relief pockets in piston tops for valve clearance would need to be included (subtracted) in measurements too. At the sizes we are talking about, even one CC is signifigant to the calculations.
Remember, as someone previously mentioned, just an overbore causes a compression ratio change, as you are then squeezing more cc of fuel/air into an area where the cylinder head displacement has not changed (although the squish area has). All this can be calculated too, but again, it requires hard data (measurements) or at least estimates.
Another nasty little issue someone brought up: Heat. That is the killer, and where the deal starts to go south if you get too power greedy. Hence my hesitation to buy into a deal of maximum bore AND compression ratio. You can toss around talk about what might be a safe compression ratio all day, and it doesn't mean squat, unless you also consider how far the cylinder has been punched out. Both of which are going to raise the engine temp. and though I live within a couple of miles of a drag strip, an engine which will only run a few minutes before overheating is of little interest to me. Also, while I'm interested in eventually adding an oil cooler, I don't want any piston/cylinder/head issues dictating an oil cooler as a necessity for my engine's survival on the street.
So... here is my opinion, and what will keep me interested in pulling my wallet out to the tune of $150 neighborhood: Keep the numbers reasonable on this first attempt. Either go for the big CC and a small CR boost, like 97mm @ 9.5:1 ... OR ... go conservitive on the CC and still keep the CR reasonable, like 95-96mm @ 10:1. As I stated earlier, if it were entirely up to me, I would go short on both and do 96mm @ 9.5:1 and see how that worked before throwing more money into the venture.
I would hope those numbers would be safe on premium pump gas, but honestly I think even those conservitive numbers are a risk. I personally wouldn't care to press it any farther on a first try.
Nobody will mistake me for Capt. Kirk and "Boldly going where no man has gone before."
All I want to do is sneak up on a few horsepower here and there. My ideal end game would be to reach the infamous one H.P./C.I. performance benchmark, without losing the beloved bottom end torque. I'm thinking 40-45 H.P. should be attainable without serious reliability issues. Maybe as much as 50. By then I'd expect the beginning of some serious trade-off in durability.
Ya got my 2¢ again