A guy that I work with was telling me that some ecotecs dont have EGR valves. He was saying that because of the timing on the cams they don't need an EGR because at lower RPMs some of the exaust gasses dont escape/are still in the combustion chamber. I have heard of people playing with DOHC cam'ed cars and thier cam timing to pas smog like this WITH the EGR hooked up and working.....but I've never heard of a newer motor not having an EGR valve....

sorry for all of that....but I was just wondering if LSJ's have EGR valves.....I just dont see how that cam timing would work for a DOHC car that had a blower on it.....

If it helps...the guy is that "full of $hit guy" at my work......I am just wondering if there is any truth to what he is saying about LSJ's/ECOTECS......THANKS....If this post should have been somewhere else....My bad....

 

honestly haven't looked under the hood of the cobalt for the egr so i'm not sure. years ago though gm had a 3.3 liter v6 that didn't have an egr so it is certainly possible.

 

Actually, most newer engine do NOT have EGR. EGR is really old, and newer designs simply eliminate the need for it.

LSJ in fact do not, and never have, had EGR.

In fact, the L61 engine had a casting provision for it in the original design, but never used it. And now, the current production engine deleted the casting.

 

It's actually not that exhaust gasses do not escape it's that on the intake stroke during the slight period of overlap some exhaust is sucked back into the cylinder which of course helps cool cylinder temps to avoid nox emissions.