Has anyone figured out if you want minimum or maximum overlap?

 

Relevant to my interests.

Hopefully someone has some good info for us. I plan to experiment with it later, but for now its minimal advance in cruise cells for the next few tanks. Tuned on the lean side and hoping to achieve decent mileage on e85.

 

I might have some relevant info from a toyota engine I can post when I get home. The pdf is on my home computer.

 

Since I cant seem to upload the file here is the link:
http://rav4world.com/pdf/2009/2009_R...w_Features.pdf
Pg 73 should have the relevant information.

 

That suggests big overlap to get EGR effects.

 

These 2 things go hand in hand though. Another thing I would suggest is go digging through the Ecomodder forum and see if you can find more information about cam timing in relation to improving MPG.

 

I havent passed the sniffer test here with my 04 motor due to high NOx. I need to get the car back on the road within a few days. This would be much easier than plumbing and controlling a stock egr valve.

 

Excessive overlap can increase HC too because of fuel going straight out the exhaust.

 

When does overlap occur on a stock VVT engine?

 

You mean in the stock mapping? Midrange RPMs, dunno how it changes with throttle position / load though.