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Discussion Starter #1
While at the dealership today,3 techs and I sat and talked about these 2 motors(35/45).Neither uses an EGR,but Infiniti is considering this mod backward,because the cam timing is used to clean it up(it is not that the motor runs clean,they use vvt to compensate for the absence of the EGR.Without the variables of the ECU there would be a serious lope at idle(cam duration),which the ECU can smooth out and why(plus calibration) these motors come alive above 3000 or 3500rpm.
With a EGR in place the car would be smoother at idle,make more bottom end torque and still give that kick above 3500..
The absense of the EGR makes the notor thirsty(cam duration/overlap) which the EGR would get around.

While some valve timing comes through the sensors(modifiable with a piggy back),most is in the ECU,So re flash is critical not a piggy back for best gains.

Hugh got a chance to drive my car focusing on the shift control,so he has more feel to solve the problem.I was finalizing my brake mods.
 

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brnjugfx45 said:
While at the dealership today, 3 techs and I sat and talked about these 2 motors (35/45).
Man, you're so lucky! I love TO Infi to death, but every time I want something "different" (oil level to 6.5 qt, +2deg timing bump) they act like I'm speaking Greek or something- I'd give anything to have 'em know something "extra" about the car!
 

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Discussion Starter #4
If you check...all cars do not have to have an EGR.

They decided who to ask on the shift mod from their training workshops.

I have been fortuate with my relationship with techs with all the cars I have ownedWhile under warranty with my GN,the mechanics would hide my car if a factory rep was in the shop(this was a huge dealership and did not require warranty approvals ,but the rep showed up every once in a while.
 

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For all us retards that don't know what an EGR is: (I had to look it up)

Exhaust Gas Recirculating Valves
What are they? What do they do? How do they fail??
EGR Valves have been around for a long time. Way back in 1972 GM used them in an attempt to reduce emissions of oxides of nitrogen (NOx) which were a major cause of air pollution, mainly photochemical smog, that kind of smog which is formed when strong sunlight shines down on the exhaust gasses we puke out of our tailpipes by the billions of cubic feet a day.

A short chemistry lesson is in order here. It was discovered way back when, that high combustion chamber peak temperatures (the really short duration high temperatures near the end of the combustion process) caused oxygen and nitrogen to combine chemically and form these oxides of nitrogen mentioned above. Most of the anti-pollution devices of the day did a pretty good job of reducing the other bad by-products of combustion, namely excessive hydrocarbons and carbon monoxide, however they tended to induce the formation of oxides of nitrogen. Something had to be done else we would all die of smog diseases.

The automotive engineers figured that they needed to do something to lower the peak combustion temperatures which only occurred under certain high load driving conditions. They figured they could do so at the expense of power and fuel economy but what the heck, ya can't have everything! If they could only add something to the combustion chamber that would act like sort of a fire extinguisher to cool the combustion temperatures that would do it.

So they invented a way to allow some very inert gas to get back into the combustion chamber only when needed. They needed a source of this gas - it wasn't air, cuz that contains oxygen and nitrogen which caused the problem in the first place. So they chose carbon dioxide. Where to get a supply of carbon dioxide . . . ??? Hmmmm, how about the exhaust system? That is mainly carbon dioxide and water (plus a zillion other noxious chemicals) Suppose we allow some of the exhaust gas to get back into the intake manifold under strict control and only when we need it? That would cool the combustion chamber and prevent the formation of the NoX. Maybe we should call it recirculated exhaust gas (REG??). But a guy named Reginald voted no cuz he didn't want his name associated with a car part, so they called it exhaust gas recirculation (EGR) since there was nobody around with that name.
 

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Discussion Starter #6
EGR was a quick fix to an emissions problem that simply required a manifold/head mod to work.When they failed,they were rarely fixed because the car ran better(they could leak and make noise).They showed up after the air pump fiasco back when...as I recall.
Gov't requires a clean exhaust,and cats.Any calibration engineer will confirm that you do not need cats to be clean.But,you may not tamper with any of the emissions equipment that came with the vehicle. :roll:
What impressed me about the conversation is the on-going think that is occurring on a motor that has been around and works.
 
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