I really, REALLY want to run a HSR or LT1 intake, but is there anything I can do to get around the EGR/higher noX issue. No visual inspection - just a sniffer.

I'd luv it, but don't think I'll get it

 

A longer duration cam with slightly more overlap will create a little reverse flow at low RPM, satisfying the EGR requirement. That's how the LT4s got away with no EGR valve.

 

nox the gas is created after 2,500 degrees.....and the higher the hc the lower the nox so i would say run it slightly rich, and a hudge cat on there

not the $99 special you want a HUDGE cat to pass sniffer, also is check engine part of your smog??

 

HUDGE is a brand name, or just a way of saying one big S.O.B.

Actually, I want to run a LT1 Convert. or a HSR, but need to pass emissions testing, so.... I guess lots of fuel, and a big mudda of a cat is the way to go - well, plus a big cam

 

A cam with enough overlap to self-EGR might not have enough vacuum at idle to keep the computer happy.

 

Like a sledge hammer in the middle of the night, crushing my happiness with truth....

 

Less timing in the map where the testing is performed will reduce NOx. It must be a dyno test if they are checking NOx. Almost no NOx is formed with no load. If you're changing the intake and cam (I kknow you didn't say you're changing the cam yet, but as long as the intake is off...), you'll need to do some PROM tuning anyway, so, you can make a temporary "emissions test" calibration bin easily.

 

Very true.

You can counter this by setting the idle a little higher and use a custom prom. I have seen custom PROM settings that allow for significant retard of spark on idle with a very progresive curve on throttle.

If you want to win the emissions test game- you'll need to burn your own chips and use a wide band O2 sensor to tailor your chips. To be honest- you'll get your money's worth out of tuning that way too.