emissions tunning
emissions tunning For those of you who tune your own vehicles and are cammed...What are you adjusting to pass emissions? I got to pass emissions again by october but I just cammed the car this winter. All the emissions equiptment on my car is functioning, but if my memory serves me right, the car just barely passed without the cam/stall and some other goodies 2 years ago...
Right now my cruising afr is pretty close to 14.7, should I be leaving it like that, or should I be leaning that out for the test? Also, how about the spark timing tables, should I load the stock one back in or should I be fine with added timing? anything else I should be looking at?
Right now my cruising afr is pretty close to 14.7, should I be leaving it like that, or should I be leaning that out for the test? Also, how about the spark timing tables, should I load the stock one back in or should I be fine with added timing? anything else I should be looking at?
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For those of you who tune your own vehicles and are cammed...What are you adjusting to pass emissions? I got to pass emissions again by october but I just cammed the car this winter. All the emissions equiptment on my car is functioning, but if my memory serves me right, the car just barely passed without the cam/stall and some other goodies 2 years ago...
Right now my cruising afr is pretty close to 14.7, should I be leaving it like that, or should I be leaning that out for the test? Also, how about the spark timing tables, should I load the stock one back in or should I be fine with added timing? anything else I should be looking at?
Right now my cruising afr is pretty close to 14.7, should I be leaving it like that, or should I be leaning that out for the test? Also, how about the spark timing tables, should I load the stock one back in or should I be fine with added timing? anything else I should be looking at?
How aggressive is your cam? You still have the 3800 V6?
Easier thing... increase idle to 1100rpm. You can probably advance timing as well.
As far as Closed Loop AFR... you cannot adjust it with tuning... it will always hit around 14.7:1 due to O2 sensors.
If you barely passed without a cam... I suggest you take a look at your cats... as this will be more of an issue now.
How aggressive is your cam? You still have the 3800 V6?
Easier thing... increase idle to 1100rpm. You can probably advance timing as well.
As far as Closed Loop AFR... you cannot adjust it with tuning... it will always hit around 14.7:1 due to O2 sensors.
How aggressive is your cam? You still have the 3800 V6?
Easier thing... increase idle to 1100rpm. You can probably advance timing as well.
As far as Closed Loop AFR... you cannot adjust it with tuning... it will always hit around 14.7:1 due to O2 sensors.
Yes I still have the 3800 v6. My idle is set at 850 right now I believe. I am beginning to advance my timing and trying to smooth out the graph.
I dont know how aggressive you would consider my cam, the specs are -210/220 @ .050 -.320" lobe lift on the intake, .512 with a 1.6 rocker ratio-.320 lobe lift on the exhaust, .512 with a 1.6 rocker ratio -112 lobe separation.
The cat is still original.... I could force it to stay in open loop if that will help. As far as the closed loop afr, when I was calibrating the maf sensor early on I was getting an afr of around 16...I finally got the part throttle down to around 14.7ish, so I dunno....
so whats the methal hydrate do? and what does the raised idle do?...just curious...a couple people have told me to raise the idle...
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Verdad Gallardo Two more questions
1: does anyone know where to buy methal hydrate in Toronto? and how much do you add per litre of gas?
2: has anyone heard of shops checking the limit of your idle? I've heard that on one of the emissions stickers on the car there is an idle limit of 899 or something like that, and if you are above that idle they will automatically fail you?
1: does anyone know where to buy methal hydrate in Toronto? and how much do you add per litre of gas?
2: has anyone heard of shops checking the limit of your idle? I've heard that on one of the emissions stickers on the car there is an idle limit of 899 or something like that, and if you are above that idle they will automatically fail you?
Two more questions
1: does anyone know where to buy methal hydrate in Toronto? and how much do you add per litre of gas?
2: has anyone heard of shops checking the limit of your idle? I've heard that on one of the emissions stickers on the car there is an idle limit of 899 or something like that, and if you are above that idle they will automatically fail you?
1: does anyone know where to buy methal hydrate in Toronto? and how much do you add per litre of gas?
2: has anyone heard of shops checking the limit of your idle? I've heard that on one of the emissions stickers on the car there is an idle limit of 899 or something like that, and if you are above that idle they will automatically fail you?
2. Limit is 1250rpm. Automatic fail above that. I'd suggest setting it to 1100 for safety.
Mark
ok perfect...last question I did some research about the methyl stuff (or I guess gasline antifreeze)...I heard that it is actually not a good idea to be using it, since it can actually do engine damage, and eat up the pistons...anyone have any opinions on this? I want to insure I pass emissions, but not at the cost of an engine...my car has high milage on it (227k), I don't wanna do anything that might hurt it.
ok perfect...last question I did some research about the methyl stuff (or I guess gasline antifreeze)...I heard that it is actually not a good idea to be using it, since it can actually do engine damage, and eat up the pistons...anyone have any opinions on this? I want to insure I pass emissions, but not at the cost of an engine...my car has high milage on it (227k), I don't wanna do anything that might hurt it.
Mark
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Joined: Nov 2005
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If you are playing with hp tuners, then go for a drive and try to get your ltft's to +-5 with the MAF disabled. This will require a lot of driving 1hr min over traffic, hills, stop go etc. Try to hit every table possible while driving. Manual cars have an advantage here. Once you have your VE tables adjusted enough to match, activate the maf, and make sure you get no KR on quick throttle transitions and that your ltft remaint in the +-5 range. If not, adjust the maf by hand in small 1% increments to get it in line with the air coming in with the map tune. If your cam has a bit of lope, raise your idle rpm to as high as you can go without failing I think 1250 is max or something.
If you get the VE's in line with your O2 sensors, you will be running as close to stoich as possible. This is as clean as it gets and your cats will do the rest. To give you an idea, I passed in the middle of winter during a -20 cold snap with my thermostat recently replaced(1 month of broke thermostat in -30 temps not fun). No oil change, no special additives, no air filter change nada. I wasn't even close to failing.
Car is cammed, true dual exhaust over the axle, off the shelf magnaflow ODB2 cats, all bolt ons etc.
If you get the VE's in line with your O2 sensors, you will be running as close to stoich as possible. This is as clean as it gets and your cats will do the rest. To give you an idea, I passed in the middle of winter during a -20 cold snap with my thermostat recently replaced(1 month of broke thermostat in -30 temps not fun). No oil change, no special additives, no air filter change nada. I wasn't even close to failing.
Car is cammed, true dual exhaust over the axle, off the shelf magnaflow ODB2 cats, all bolt ons etc.
Go to Canadian Tire , and in the Interior Paints section you'll find a 4L jug of methyl hydrate which will cost about $8.00. Pour the entire 4L in a 1/4 tank of gas just to do the emissions test. Then once it's done immediately fill up your gas tank. This should work.
