Armond, thank you for your thoughts. It makes much more sense now. Its what I intended out of this thread, really. This brings me to another question, though. From what you are saying, we cant have the best of both worlds, right? I plan on rebuilding with 8.5:1 pistons. I plan on at first, running 10 psi, then going up to 15 psi. What do you think will be the best setup for this? You are saying to run around 11.0 - 11.3 or so A/F ratio, at WOT boost? With NO spark retard, just running the stock ecu WOT timing curve? Is that right? How high of boost can I go with the 8.5 compression, without using any spark retard, or before detonation sets in? I'm very curious.. I as are many others are going this setup, or may already have their motors set up with this or close compression ratio. At what point do you think we *need* to retard timing? From what I thihk you are saying, we need to add more fuel, increasing the actual A/F ratio, as boost pressure increases, INSTEAD of retarding timing? If thats the case, then all of the literature i have read up on, ect..is wrong? All of what i have read says with increased cylinder pressure, you need to retard timing, AND add the fuel of course..

What do you think of this. They talk of a n2o setup, but its still forced induction:

"Understand that, in our quest to delay cylinder pressure’s peak time, more is not necessarily better. Instead, consider that the ideal cylinder pressure would be just short of detonation pressure and this pressure would be maintained from top dead center, and as long as possible after TDC. If timing is really late, you won’t build enough cylinder pressure to start the car, let alone drive it. The 1000 PSI pressure in the example is not the maximum allowable combustion pressure but, rather, a comfortable pressure for illustration of the work principle.

Some nitrous manufacturers recommend, "retard the timing two degrees for each fifty horse power of nitrous". Other nitrous kits have the flame speed artificially slowed by the intentional use of a rich fuel to nitrous ratio. The maximum performance engine with a heavy nitrous load must achieve peak cylinder pressure progressively further after TDC. The heavy load engine will have the fuel and oxygen mix to make high cylinder pressures, with the combustion chamber size being drastically increased due to the piston being on its way toward bottom dead center. The strongest engines have less compression ratio, less spark advance, and more nitrous.

I have tried to explain the reason for a spark retard system in a Nitrous engine. However, many people just don’t like the idea of any retard. They say, "retard timing and exhaust heat goes up". It usually does in a stock nonnitrous engine because lower peak cylinder pressure slows the burning. If the timing is retarded in a non-nitrous engine, the exhaust opens before the fuel mix is finished burning and exhaust temperatures go up. Piston temperatures usually go down and exhaust valve temperature goes up. In the nitrous engine, exhaust temperature goes up for several reasons. The first is that the power output has gone up considerably. More power usually produces more waste heat. Second, the need to keep maximum cylinder pressures within reason has dictated that the biggest part of the fire happens closer to the exhaust valve opening time. There just isn’t enough piston travel to extract all the energy out of the charge before the exhaust valve opens. Now, we could and sometimes do, open the exhaust valve later so more combustion pressure energy can be used to turn the crank. The trade off is negative torque on the exhaust stroke. If we still have significant cylinder pressure in the cylinder as the piston moves from BDC to TDC on the exhaust stroke, your net Hp falls drastically. A real problem at higher RPM."

This is the link to all of it: http://www.kb-silvolite.com/page14.htm

13.5 @108 MPH-2.2 60ft(stupid FWD!)
S16G @ 18 PSI/FMIC/Running on MegaSquirt II (Now with sequential
fuel injection)
My webpage: http://eclipsed4evr.home.comcast.net
-1998 Mitsubishi Eclipse RS-T- "Toy"
-1992 Plymouth Laser Turbo AWD(SOLD)
-2000 Honda CR-V(daily)