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Emissions reduction for VAAS cert

Skylarking

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@chance23 what are the rules about idle speed?
Can you increase base idle and reduce fueling a little (get rid of the rich lumpy idle)?
Can you free up intake restrictions with new air filter?
Can you run E10 or a higher alcohol fuel blend (assume they run cleaner)?

Shouldn't these measures be enough to get you that little bit less CO2 % and allow you to pass the next test?

Just asking questions because I don't know and I'm interested in the outcome ;)

@Lacksballs will cats help with a rich lumpy idle on regular 91RON (assumeing that is what was in the tank during teh previous test)?
 

Lacksballs

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I doubt very much the rich lumpy idle will change, however what I would suggest is drain all the remaining fuel out of the vehicle, replace the fuel filter & fuel up with the fuel you intended using ie 98/E85 etc. Fit a pair of high flow cats & the appropriate pollution canister for the engine, check your thermostat operation (engine needs to be up to normal operating temperature as quick as possible or will run rich at idle for a lot longer) then arrange to take your car to a reputable tuner. They will be able to do a health check on the state of the engine then tune accordingly. You really need access to a 3 way gas analyser or you could be spending another $300 on the repeat test for nothing!
 

chance23

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Yep, was thinking that about the idle speed yesterday. There’s nothing that says it can’t be higher. Increase vacuum a bit and help suck a bit more oxygen in for more burn.
I’ve already dumped the fuel, cleaned the tank and changed fuel filters and filling with 98 (although E85 might be the go).
Changed air filter (it’s a 14” x 2” one).
High flow cats where on it, but the engineer stated they won’t be doing much for the emissions due to burn temps not getting high enough and apparently seeing some (carb) engines with big cams fail due to sucking back from the cats?
From my understanding the cats more affect the nitrogen than the carbon monoxide anyway.
Just seen that I can hire a 4 way anayliser from Kennards for about $120 for the day. Shame Victoria doesn’t offer free emissions testing like Sydney does.
I’ll keep this update until I get a resolution.
Thanks for the advice everyone, it’s appreciated.
 

Lacksballs

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Hence why some manufactures added "air pumps" to their engines back in the 80's to over come this issue.

See how you go with the gas analyser, adjusting the idle speed, timing & mixtures. What you may need to know at what points the tests are done so you can replicate the same conditions & record pre & post your adjustments.

OR you may need to replace your cam with a more STD grind to pass the tests!

good luck....
 
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