what are the good and bad things about a high compression motor?

High compression requires high octane fuel, pump premium may not be good enough, you may also need to add octane boosters, add xylene or tolulene (115+ octane stuff sold in your paint store as paint thinner) or use aviation fuel or racing fuel if you have access to them. High compression generates higher heat and stress on valves, piston rings, head gasket etc. High compression generates higher peak temperature so higher NOx emissions.

The advantages of high compression is that you also get high expansion ratio so you extract more energy out of the fuel. Some folks like Toyota Prius use Atkinson cycle which is basically a high compression engine with the overlap screwed up on the intake stroke to not completely fill the cylinder, and then benefit from the compression only on the power stroke for optimal expansion.

http://www.curbsideclassic.com/blog/the-atkinson-a...

I agree with three55..

Keep in mind that big blocks don't really like high rpm's, long term.. Also keep an eye on the oil.. the motor is most likely stroked and depending on stock size to stroke size the piston oil ring can intersect the wrist pin and can cause oil comsumption...

Keep it cool. Watch transmission temp with the stall converter, be sure to have some kind of cooler.

good luck

tim

Goods: lots of power, fairly good fuel economy if done right

Bads: lots of wear/tear on engine, requires a completely "built" engine, reduced reliablity.

Reliablity is the reason why a lot of older American cars had big displacement V8s. The idea was that if the engine had big parts, it didn't have to work as hard(meaning it didn't need to rev high etc).

800hp is more than enough for the street. Not every car on the road is a Camaro ZL1 or Mustang GT500.

What is the compression? I've found that I get along just fine with premium 93 octane and running 10.6 to 1, If you have a dragstrip closer and am running more than 11 to 1 compression you could always buy their 110 octane. I'm sure you probably tweaked up the timing to avoid detonation and ping/knock.