Emissions help
- Thread starter 87targa
- Start date
Umm he should look to do the basics ..... Plugs, wires, and make sure his base timing is 10 degrees.
What are your mods?
What are your mods?
un burnt fuel, leave the timing at 10 degrees, check your o2 sensors to see if they are working properly(good wave form), and ignition. are you boosting ? maybe boost leak ? keep us posted
First test. i'll be doing a retest here in a few days.
all the numbers are in ppm
HC
199 max Mine:827 @ 15mph
184 max Mine:865 @ 25mph
CO
0.82 max Mine: 12.44 @ 15mph
0.72 max Mine: 12.46 @ 25mph
NO
1949 max Mine: 480 @ 15mph
1749 max Mine: 537 @ 25mph
Mods:
Hi flow cat, 750 injectors, 60-1 turbo (not in boost during test), 255 walbro, stage 2 crower cams (Adv. Dur.: 264264br>Dur @ .050: 220220br>Lift (in): .336"/.336" Lift (mm): 8.53/8.53), maft pro to tune, wideband o2.
the plugs are new, wires are magnecor, timing is advanced 2 degrees. The car past last year with the same mods other than the cams. I have not fully tuned the car with the new cams (at least down low). with the cams installed, i am running pig rich (down low) on my wideband. I am guessing that if i just tune out the car i should pass???
i'll keep you all posted on what happens
all the numbers are in ppm
HC
199 max Mine:827 @ 15mph
184 max Mine:865 @ 25mph
CO
0.82 max Mine: 12.44 @ 15mph
0.72 max Mine: 12.46 @ 25mph
NO
1949 max Mine: 480 @ 15mph
1749 max Mine: 537 @ 25mph
Mods:
Hi flow cat, 750 injectors, 60-1 turbo (not in boost during test), 255 walbro, stage 2 crower cams (Adv. Dur.: 264264br>Dur @ .050: 220220br>Lift (in): .336"/.336" Lift (mm): 8.53/8.53), maft pro to tune, wideband o2.
the plugs are new, wires are magnecor, timing is advanced 2 degrees. The car past last year with the same mods other than the cams. I have not fully tuned the car with the new cams (at least down low). with the cams installed, i am running pig rich (down low) on my wideband. I am guessing that if i just tune out the car i should pass???
i'll keep you all posted on what happens
you just answered your own question... if you KNOW your running pig rich why even bother trying to pass smog???
you could also advance/retard the cams to help some more...
and do you have a fuel pressure regulator?
you could also advance/retard the cams to help some more...
and do you have a fuel pressure regulator?
Stock cams, stock cats, pass smog. That simple. Your cams have overlap that the stockers don't. Well, more than stock anyway. So the intake charge is sent right out the exhaust valve.
And not having a real cat never helps either. A high flow cat on a clean car, mostly stock, might cut the mustard. Ignition timing has no effect on air fule ratio, and he is pig rich, as figgie correctly said.
And not having a real cat never helps either. A high flow cat on a clean car, mostly stock, might cut the mustard. Ignition timing has no effect on air fule ratio, and he is pig rich, as figgie correctly said.
Subtract some fuel man ..... you already know one of your major issues.
Think about it .... "I know i am running pig rich and I fail my emission due to a high HC count and HC means unburnt fuel" .... :slap:duh!!
Think about it .... "I know i am running pig rich and I fail my emission due to a high HC count and HC means unburnt fuel" .... :slap:duh!!
^ Except 98% of the info you received is BS. And next time you want help try posting the test results correctly. If you don't know how to read the report scan it...
jetjock;965134 said:
jetjock, i know that i have to be careful of what people say and what i take as good info.
I am not going to play with my timing. i do not have adjustable cam gears so i can not reduce over lap. the only thing i have is to tune it and lean it out a little. others here locally (who know about tuning and how to read the emissions report) have said what i thought, which is, i'm way rich. I just wanted to know what people here thought.
i don't have a scanner so here is what the results say.
15mph, 1672 rpm:
%CO2 measured: 5.2
%o2 measures: 0.0
HC (PPM)
Max: 199
Measured: 827
CO%
Max: 0.82
Measured: 12.44
NO (PPM)
Max: 1949
Measured: 480
Result: Fail
25 mph, 1845 rpm:
%CO2 measured: 5.2
%o2 measures: 0.0
HC (PPM)
Max: 184
Measured: 865
CO%
Max: 0.72
Measured: 12.46
NO (PPM)
Max: 1749
Measured: 537
Result: Fail
from what i know, because the co and hc are high, i have partial and unburnt fuel. if my hc were high only, i would be rich (is that correct?), if my co were high only, i would be lean (is that correct?). if my co and hc are high together, i am way rich (right?)
anyways, Does that format of the test results help any?? i'll lean out the car a bit and see what happens.
late
The overlapping cam also reduces cylinder pressure. That simulates a weak ignition. In addition to spitting your air/fuel mixture right out the pipes.
CO-carbon monoxide is a result of partially burned fuel. You did not have enough oxygen for the combustion to complete.
HC-hydrocarbon, is raw fuel in vapor form.
CO-carbon monoxide is a result of partially burned fuel. You did not have enough oxygen for the combustion to complete.
HC-hydrocarbon, is raw fuel in vapor form.
Ok, that's better. I withdraw the 98% comment and offer my apologies. The problem I had was that HC is not by any means a sole indicator of richness. You can be lean and have high HC. Plus it can also be caused by non-mixture related problems. Also CO isn't reported in ppm as previously stated. Now that I see all the numbers it's clear the engine is indeed rich.
Rich indeed at 8.99:1.
It is interesting to note that 440/750 * 14.71 = 8.63 (compare with 8.99)
I suggest going back to 440s to pass.
It is interesting to note that 440/750 * 14.71 = 8.63 (compare with 8.99)
I suggest going back to 440s to pass.