2QUIK6

Anyone have a ZZ4 cam with no EGR on a TPI that has to pass NOx emissions testing on a treadmill/dyno?
Has anyone done it with no EGR?
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WE used to have the standing idle and high idle test which did not measure NOx output, now we do and am worried I will not pass.
Thanks

AlexJH

Yup.

Make sure you disable EGR in the prom (this is vital). I also retarded the timing, and used G2P in the tank.

Previous owner passed with 1% (stock cam). I passed with 15% with the ZZ4.

SLOW91TA305

Whats this G2P you used in your tank?

AlexJH

Guaranteed to Pass.

93ND500

2QUIK6, been a while......

As for your question, my truck passed NOx running a similar setup. But I also had did some prom work to help it along.

2QUIK6

Hey Will, ya, hadn't been thinking too much about the truck, been playing with my new toy, the 79 TA. we just went to the treadmill emission tests here, so in preparation, I'm about to get a TCI tranny controller module to control the 4LE60 and rid myself of that dual stock ECM setup I have, that will clean up my wiring harness quite a bit.
Hey, with the stock TPI intake/plenum, do you think there's any breathing restrictions with the ZZ4 cam below 3500 rpms? My thoughts that the stock intake/plenum aren't restricting me until I get above 4-4.5k rpms which would be rare on the street.

93ND500

I've still got two computers too, but I have a 700R4(4L60) waiting to go in. I'm going to have the TPI computer to control everything. As for the stock intake system....it should be fine for what you doing with the truck.