VEs AFRs and Widebands
Turbo Mini Forums

I dug this up from wayback.

I'm plodding away at my simulations and this data is just about the only thing you can find about dual afr readings on an a-series carb'ed engine.

I have a 1D simulation model (revision mk 37 ish, it very easy to makes small mistakes). It now incorporates every diameter CSA change and angle in the entire siamese port ( intake and exhaust) correctly ( I hope) .

Results seem pretty plausible all round but there it still the charge robbing (its there really?) issue. If you feed a say 12.5AFR mix into the system it does produce different egt's for the inner and outer cylinders but only 20 to 30 degrees, not 150 like reported here. As it is 1D it can't do anything with inertia of fuel droplets and such, yet it still gives an EGT difference ( more AF mass thus more heat I guess).

What the sims does show is a that the inner and outer cylinders are two fully different animals with markedly different power levels. It you look at the mass flow traces ( and that is pretty well done with GPBlair type 1d sim) there is no charge robbing in the sense that the overlap causes the mass flow of the other cylinder to suddenly drop or anything like that.

is there more data available ?

cheers

That sir, is not rust, it is the progressive mass reduction system

http://aseriesmodifications.wordpress.com/

I have a huge amount of simulation data.

Start a new thread as most of the above is out of date.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."