Quench or Squish are commonly referred to as the distance from the top of the piston to the flat spot on the head. For example, if you have a zero deck block, the piston is level with the deck. So your quench or squish distance would be the thickness of your compresed head gasket. .040" -.035" is usually accepted as a good distance for steel rod engines in iron blocks.
The "squish" or "quench" issue isn't as important in a low compression engine. In fact, it's almost nonexistent. There are other ways to induce swirl, mainly chamber or piston dome design. Quench becomes more important as compression moves up because of the extra heat build up. That's when sharp edges in the chamber get hot - hot enough to cause detonation - and don't get the chance to cool off before the next cycle. There are several production engines that are on the far side of quench still made -- the AMC/Jeep 4.0L is one of them. Compression is 8.7:1, but the piston is around 0.060" down in the hole -- and I think it's more. Don't recall off the top of my head, but over in the "strokers" yahoo group (putting 258 cranks in 4.0L blocks to create 4.5L-4.7L sixes -- the 258 has 0.44" more stroke than the 4.0L, otherwise it's a drop in) this has come up a lot. The "budget stroker" uses the 258 crank and rods, and stock 4.0L pistons. Compression would go up to nearly 10:1, but a cam is used to bleed some pressure off to get it back down to an effective 9.2:1 or so. The engine can handle that without detonotation. The piston is about 0.080" down in the hole with this combo. I'm running one like that now, but added dish to the pistons rather then use a high overlap cam to get compression down. I had some pinging under medium loads before dishing the pistons (with a router while still in the block, no less!!), but now I never get pinging and have the same power though I lost 0.5 points in compression. How? I'm using the early Jeep EFI, which had a knock sensor (87-90). Timing was being turned down as far as it would go most of the time, but with the lower compression it's rarely turned down.
I think you are going to like your light car with a 305. Mine has a 305, saginaw 4 spd, and 3.08 gears. The car weighs in at 2200 lbs. It started with a 4.11 gear, but first was useless, and longer trips were a bear, but around town that gear was great. A three dueces setup disguses the engine and works well. The last time I checked, it was getting 16 mpg and still runs like a scalded ape.
not the lenth but the whith if you use say a 10mm wire and want to retard the spARK TO JUST ONE cyclinder in thirory a 7mm or a 6mm it would slow or retard the spark a bit dew to resistince but that is just a thought
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