Thanks for the detailed response. Let's explore the option of introducing the exhaust gases before or after the carb.
On Mon, 2008-12-29 at 22:46 -0800, George Bearden wrote: > It displaces BOTH fuel and air, the mixture, not just oxygen selectively. > Thus the mixture remains almost the same. > > > wouldn't that really richen the O2/fuel ratio? > > No. Less fuel AND air. > In my application (or at least the way I saw it in my head), the exhaust gas would be intruduced into the inside of the air filter, inlet end of the carb (hopefully mixing with and tepmerature equalizing with the incoming fresh air source before finding it's way to the carb throttle plate). Since there is no EFI system, no immediate mixture setting changes at the carb will happen. The intakes gases/fuel mix should remain pretty much unchanged, but the fuel/O2 mix should effectively richen by virtue of the reduced concentration of O2 in the intake gases, but unchanged fuel delivery. > > Isin't richer farther from (and cooler than) detonation rather than > closer? > > Yes. > Or would it be better to do it the GM way, introduce the exhaust gas after the throttle plate? Then it would maintain the air/fuel mixture (as you say), but mostly reduce the effective power output without also richening the mixture. I kind of think enrichening it some might be a good thing if this is to happen at high energy (near or already pinging) combustion chamber conditions. Or am I just going to make alot of unnecessary soot (some if it on the intake side of my throttle plate)? Is it possible that HOT exhaust gasses introduced right after the carb might actually ignite the air/fuel stream in the vaccuum portion of the intake manifold? Should the gasses be routed through a cooling tube, maybe 1/2 or 3/4 inch x 4 or 5 feet long before entering the intake manifold? or maybe go through something like an intercooler? jg
