Emissions?
TECH Addict
Joined: Nov 2005
Posts: 2,379
Likes: 2
You really need to work on that tune.
With a LS1 224 cam on a 0.561 lift and a 112lsa, stock heads, long tubes, true duals I was still well within 98 LS1 limits which are just as tight. The idle had a good chop to it.
I passed again at a random testing facility on a 230 0.615 115 LSA cam and 5.3L heads.
With a LS1 224 cam on a 0.561 lift and a 112lsa, stock heads, long tubes, true duals I was still well within 98 LS1 limits which are just as tight. The idle had a good chop to it.
I passed again at a random testing facility on a 230 0.615 115 LSA cam and 5.3L heads.
the 224 cam is 224/224 duration is it not? that's alot less than my 230/240 duration cam on ported/polished heads, with the biggest valves we can fit stuffed into them lol.
Now factor in that you guys also have 2 cats, while we have 1, and consider that my shitty aftermarket one probably blew half the contents out...yes my tune went pig rich as I didnt compensate for the cylinder I disconnected (injector/spark) and the car tried to compensate. Yes the tune will make a bit of a difference, not 4000ppm worth
Now factor in that you guys also have 2 cats, while we have 1, and consider that my shitty aftermarket one probably blew half the contents out...yes my tune went pig rich as I didnt compensate for the cylinder I disconnected (injector/spark) and the car tried to compensate. Yes the tune will make a bit of a difference, not 4000ppm worth
If both are a go, I'll be looking for a pair of cats....I'll know in the next month/few weeks I think.
Launching!
Joined: Oct 2012
Posts: 258
Likes: 0
From: Canada
Guys with big cams and have to run the old style sniffer test, you need to back your timing huge... back to 10-12* at idle, rpm at idle set to at least 1200rpm. Will idle like absolute crap but you can get it to pass. Best way to set RPM is to find out what the test limit is for your car and set it as close to that as you can without obviously going over. My 227/229 .559 lft cam blew dam near 0 on everything when I got it to pass. The guy testing honestly thought what was coming out was cleaner than what was going in... lol He was completely dumbfounded. They thought there was no way the car could pass, and this was with the EGR removed completely and no rear O2
Guys with big cams and have to run the old style sniffer test, you need to back your timing huge... back to 10-12* at idle, rpm at idle set to at least 1200rpm. Will idle like absolute crap but you can get it to pass. Best way to set RPM is to find out what the test limit is for your car and set it as close to that as you can without obviously going over. My 227/229 .559 lft cam blew dam near 0 on everything when I got it to pass. The guy testing honestly thought what was coming out was cleaner than what was going in... lol He was completely dumbfounded. They thought there was no way the car could pass, and this was with the EGR removed completely and no rear O2
Car passed the 2500rpm, still failed idle with a 953ppm and a 2.0 CO% (200ppm and 1.0% allowed)
227/229 still isn't overly aggressive. My old 210/220 cam passed with flying colours
Bottomline is anybody that has a BIG cam, isn't passing the sniffer, and when I say big cam I am talking to anyone who has something above 230+ duration. I think the lift effect is very minimal
Last edited by LETZRIDE; Apr 6, 2013 at 12:18 PM.
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Joined: Oct 2012
Posts: 258
Likes: 0
From: Canada
We got a .610 with with just over 230 to pass this way. I failed miserably with 26* at idle with that mid size cam. Was just saying that the effect on mine was nuts running 12,this is how you can actually squeeze the big ones through using the same method. You passed the 2500 RPM because you were hiding the overlap with the increase in RPM. I bet you try 10-12* with idle RPM set to max allowed for the test and you will get through
maybe you're right...looking back at my tune right now, Im running 26* at idle for the test. But I also suppose every car is different...you guys also have the added advantage of dual cats.
The more I think about it to, it could be shop dependent/equipment dependent. Case and point...I went out to a honda dealership for the first test, and ran with my cutout open and with 1 cylinder pulled. Today I went to a different shop, ran with all cylinders firing and my cutout open and the tech couldn't even start the test due to dilution. Oddly enough the honda tech only had one sniffer in, this guy had a sniffer in each tail pipe and it booted him, I had to go close the cutout and come back.
Anyways, I have what I need for now, I'll deal with this again in 2 years if need be, by then I should have LT headers and 2 cats myself, so maybe all will be well. Maybe they'll amend the law to include any OBDII equipped vehicle to do the new test like it is in the USA.
In any event, as I was waiting around at this shop I was at today...the number of people coming in for re-test/failing the new test today was incredible. I overheard a lot of the codes to, many of them were b.s O2 voltage high/o2 voltage lean bank 2, etc.
I have a little writeup I'm doing up to showing step-by-step how to ready up your sensors...when I have some time I'll complete it (has snapshots of where to go in hp tuners etc) as I've had a couple people p.m me already asking how to do it and being a little confused. I'll link it here when I'm done.
cheers and hoping to see some of you guys at the strip this season.
The more I think about it to, it could be shop dependent/equipment dependent. Case and point...I went out to a honda dealership for the first test, and ran with my cutout open and with 1 cylinder pulled. Today I went to a different shop, ran with all cylinders firing and my cutout open and the tech couldn't even start the test due to dilution. Oddly enough the honda tech only had one sniffer in, this guy had a sniffer in each tail pipe and it booted him, I had to go close the cutout and come back.
Anyways, I have what I need for now, I'll deal with this again in 2 years if need be, by then I should have LT headers and 2 cats myself, so maybe all will be well. Maybe they'll amend the law to include any OBDII equipped vehicle to do the new test like it is in the USA.
In any event, as I was waiting around at this shop I was at today...the number of people coming in for re-test/failing the new test today was incredible. I overheard a lot of the codes to, many of them were b.s O2 voltage high/o2 voltage lean bank 2, etc.
I have a little writeup I'm doing up to showing step-by-step how to ready up your sensors...when I have some time I'll complete it (has snapshots of where to go in hp tuners etc) as I've had a couple people p.m me already asking how to do it and being a little confused. I'll link it here when I'm done.
cheers and hoping to see some of you guys at the strip this season.