Is it possible to pass emissions with no EGR?

[d0n_3d]

Just as the title says...with a good emissions chip for say 72 lb/hr injectors and a full cat on...can I pass emissions???

 

[gofstbuick]

I just reviewed a basic of the test protocol. I suspect that an emissions sample is gathered even during acceleration to 33mph. Am I correct?. If so, the EGR will help control NOx and may cause you problems. You may attempt to run the mixture a little richer (this may cool combustion temps), to compensate for the lack of EGR. One of the problems is that the east coast and mid-west have CO issues, whereas California has HC and NOx issues. So the CO cutpoints may be tighter than California. Bottom line is when you richen the mixture, you may fail CO.

 

[rob nolan]

Originally posted by d0n_3d
Just as the title says...with a good emissions chip for say 72 lb/hr injectors and a full cat on...can I pass emissions???

Yes!!! I passed with 72s and my 93 Red Armstrong chip.

 

[d0n_3d]

cool, and i think illinois is a little stricter on emissions than indiana is...awesome i have nothing to worry about then...i am going with a PT-61 turbo and 57's actually, a little milder than once previous thought

 

[TurboJim]

If you can get it to 16.2:1 at the egr sample phase and not stall, it will pass

Seriously, NOx lowers below like 12.5:1 and rises until ~16:1 then falls like a rock again.

If you have a longer exhaust duiration cam, you may benefit from "self egr" that is, the backpressure in the exhaust, with a longer exh duration, leaves some exhaust in the chamber. This exhaust is inert and takes place of the space a volatile charge can occupy. The fact this inert "mixture" cannot burn, lowers chamber temps

Another thought is to retard the timing a bit to get the combustion event to occur closer to the time the exhaust valve will be opening, thus lowering combustion chamber temps below the magic 2500* mark, which will also reduce NOx.

Without using one of these methods to lower chamber temps, you wont pass NOx, sorry. FWIW, if you try anyway, My guess is 2300 ppm

Jim

 

[d0n_3d]

Originally posted by TurboJim
If you can get it to 16.2:1 at the egr sample phase and not stall, it will pass

Seriously, NOx lowers below like 12.5:1 and rises until ~16:1 then falls like a rock again.

If you have a longer exhaust duiration cam, you may benefit from "self egr" that is, the backpressure in the exhaust, with a longer exh duration, leaves some exhaust in the chamber. This exhaust is inert and takes place of the space a volatile charge can occupy. The fact this inert "mixture" cannot burn, lowers chamber temps

Another thought is to retard the timing a bit to get the combustion event to occur closer to the time the exhaust valve will be opening, thus lowering combustion chamber temps below the magic 2500* mark, which will also reduce NOx.

Without using one of these methods to lower chamber temps, you wont pass NOx, sorry. FWIW, if you try anyway, My guess is 2300 ppm

Jim

they don't test NOx in Indiana thank god