Would it be better to use the RPM Airgap intake and lose the EGR or get a egr provisioned intake. Im going to be converting to carb sometime and this is going to be going with my zz4 engine and holley carb.

 

EGR is basically an emissions control device. The only reason to concern yourself with it is if you have to pass emissions testing/inspection of some sort.

Converting a '92 RS from TBI to carb will render it emissions-illegal. That being the case, why are you concerning yourself with EGR?

 

Because i read in a thread that the EGR is actually beneficial to the engine, like giving better gas mileage. Plus they do not do engine visuals here so they wont know its a carb.

 

If the induction & ignition systems are designed for EGR, then keeping it (as opposed to blocking it off and doing nothing else) will do what was stated.

When completely converting the system, then there is no additional benefit.

I've only had dyno sniffer tests for the last 9 years, but when I had no-load sniffer only, it didn't detect NOx's, which is what the EGR is designed to reduce. That may have changed, though, so it may be beneficial to retain the valve to pass even without a visual inspection.

If you look at a print-out from a previous test, you can tell whether or not NOx is one of the criterion.

 

FWIW, I've heard the ZZ4 cam has enough overlap that you get a little exhaust dilution of the intake charge at lower engine speeds so that EGR isn't necessary. But, no guarantees there.

 

Also the corvette heads on a ZZ4 motor don't have an exhaust crossover port to feed the manifold so an EGR valve won't do any thing if you installed it.