Emissions reduction for VAAS cert

[chance23]

morning,

Had my first inspection for my VAAS cert (mod plate) and my emission were a little high. Not extreme, but over.
Before my next test I’ll change plugs/oil/filter, lean out a bit, clean out air filter (it has a new pvc valve), premium fuel and retard the timing. Any other go to’s I can be trying. At about $300 per emission test, in not keen on doing it a third time.
308 stroked to 383, Holley 750DP, decent crow cam ( hyd roller), VN heads.

 

[DerekP]

All your valves, piston rings and sleeves in good nick?

 

[chance23]

All your valves, piston rings and sleeves in good nick?

Yep. About 50 kms on them plus a few test runs. COME heads pre assembled.

 

[Heron SSV]

I've heard E85 can give a cleaner result for emissions testing

 

[Skylarking]

Not sure what is involved in certification but I’d have thought the standards you must meet depend on the vehicle’s manufacture date and whether the engine block is from the same year or something more modern. I thought the vehicle needed to comply with pollution rules for which ever (vehicle or engine) was the later. And if the engine was a later design, all pollution crap from the year must follow the engine.

So I’d think such related info would be useful, vehicle year, engine year, do you have the latest pollution gear from the latest of either vehicle or engine? It would be of interest to forum members as would the actual results of the emission test and what gasses and %’s were found.

So far you’ve posted about your VC a VR but they were different engines. Considered a build thread for this project?

Also, as you’re paying the engineer for signing it off, surely he has some thoughts on the subject which you can share here.

 

[shane_3800]

Do they test on a dyno at road speed?

 

[Skylarking]

Do they test on a dyno at road speed?

Interesting question... maybe VW group has the answer

 

[chance23]

Apologies, been out of internet range over the last few days.

The VR was for my brothers motor, not mine. I hadn’t put a build up here yet as it’s been a long build and I wanted the rego before I posted much up and she’s close now.

It was the CO2 reading that was 1 over (5 but needed to be 4). The Nox was fine. The engineer didn’t have much advice for the emissions. He’s about the component mods. He was great with other advice, but couldn’t offer much on that. It was done at idol with an analysis stick up the pipe.

The car is a vB commodore sedan, 308 VL black motor, stroked out to 383 with vn 600 come heads (and all internals), four barrel come manifold, Holley DP 750, crow CC 242/246 @50 thou hyd roller cam (CC41725), 11:1 compression, built 3500 stall, built manualised trimatic, Ford 9” rear end, coil overs, Holley electric fuel pump/filter/regulator, pacemaker headers (2.25” pipes into 2.5” duels, into 3”), PWR radiator and a few other things I’m sure.

 

[shane_3800]

Apologies, been out of internet range over the last few days.

The VR was for my brothers motor, not mine. I hadn’t put a build up here yet as it’s been a long build and I wanted the rego before I posted much up and she’s close now.

It was the CO2 reading that was 1 over (5 but needed to be 4). The Nox was fine. The engineer didn’t have much advice for the emissions. He’s about the component mods. He was great with other advice, but couldn’t offer much on that. It was done at idol with an analysis stick up the pipe.

The car is a vB commodore sedan, 308 VL black motor, stroked out to 383 with vn 600 come heads (and all internals), four barrel come manifold, Holley DP 750, crow CC 242/246 @50 thou hyd roller cam (CC41725), 11:1 compression, built 3500 stall, built manualised trimatic, Ford 9” rear end, coil overs, Holley electric fuel pump/filter/regulator, pacemaker headers (2.25” pipes into 2.5” duels, into 3”), PWR radiator and a few other things I’m sure.

With a big cam at idle you'll never pass. testing at idle seems like a joke to me.

The bigger cam has less vaccume so your idle tune will be rich as **** trying to keep the thing running.

I assume big cam to feed the 383ci of engine.

 

[Lacksballs]

Any cats fitted???

VL Black engines had a catalytic converters (1st non leaded GMH V8's). If not fit a couple of high flow cats, any reputable exhaust shop should be able to help you out.