CGT80
1/2 ton status
The smog guy decided to be picky this time. I didn't have all my EO stickers on the truck for the aftermarket parts. I was able to dig them out of my toolbox. Luckily I saved all my stickers and paperwork from every upgrade I have done to the truck.
The problem is getting all the vacuum lines run correctly. I am missing a couple parts and my carb is now an Edelbrock performer 600 rather than a Qjet. The carb is CA legal, I just have to make sure I get it hooked up right. The last item will be to get my idle mixture set so it will pass smog. In the past, the screws might have gotten tweaked a little as it was being tested, so that it would be adjusted to burn clean
. I don't know if that will happen this time.
Hopefully some people here know a bit about the emissions systems on these trucks. I know a fair bit, but still have questions on the vacuum switches.
I have two thermal vacuum switches on the intake. One is for the early fuel evap valve on the exhaust (also called a heat riser valve), and the spark delay switch. This is the big thermal switch that has four ports. The two bottom ones loop through the spark delay valve. That valve is inline to the vac advance on the dizzy. I am not sure when this valve should be open or at what temp. I don't know the original part number. There are a few available.
The other thermal vac switch is two ports and I think it goes to the egr and fuel canisters. I don't know what temp this one should be either.
I put a vac pump on these switches, but they leak, even if I cap the ports that would go to the smog equipment. This doesn't seem right. Will these hold vacuum or do they always loose some? I thought I might be able to use a vac pump to see when the switch opens. I would dip the switch into hot water to test it.
This engine is built as much as possible while still meeting CA smog. I need to get it to pass, but I also need to make sure I can tune it for best performance when needed.
Here are the smog parts:
EGR: when should it be activated for smog specs? Does it really reduce pinging and is it beneficial even when I want to tune for performance and don't care about passing smog?
AIR diverter valve from smog air pump: When should it inject air into the headers? Should it work only at running engine temp and not when the engine is cold? Does it need timed vacuum or manifold vacuum?
Fuel vapor charcoal canisters: same questions as above.
Vacuum Advance is tied to dedicated vac adv port on carb and is ported, so this should be fine for smog.
EFE/heat riser: seems this would go to manifold vac and be routed through a thermal switch so it lets the exhaust flow freely after it warms up. This carb (edelbrock 1400) has two emissions ports on the front and both are closed at an idle. When I crack the throttle, I get a reading on my vac gauge. The one for the dizzy seems like a more smooth increase in vac and the other is more sporadic.
My thought is that if I better understand how these are supposed to work, I will be able to route the lines properly and figure out if the switches are working right or if they need changed. I don't know how many of these emissions parts are used on 49 state trucks. Maybe you Komnifornia brothers will know a bit about this stuff.
Anyone know how lean my idle screws should be to pass smog. I would imagine that too lean will raise some of the emissions and too fat will raise others.
I can post pics of my factory hose diagram, or my carb diagram if needed. I figured I would try to get this stuff working as close to the way the factory intended as possible, since our laws are crap and we also have road side smog checks and smog every year or two for my truck. I would decline to let a road side check run my truck, as they are voluntary, but I don't want to get caught with my pants down. All of the major parts on the truck are 50 state legal, I have just been sliding on the hose routing and they don't make sure some of it works because the truck is hot when it gets tested, and at least the EFE and air cleaner will not be active at that point. A little tweaking gets it to burn clean. I don't have an exhaust gas analyzer or O2 reader to see how clean it burns.
Thanks
The problem is getting all the vacuum lines run correctly. I am missing a couple parts and my carb is now an Edelbrock performer 600 rather than a Qjet. The carb is CA legal, I just have to make sure I get it hooked up right. The last item will be to get my idle mixture set so it will pass smog. In the past, the screws might have gotten tweaked a little as it was being tested, so that it would be adjusted to burn clean
. I don't know if that will happen this time.Hopefully some people here know a bit about the emissions systems on these trucks. I know a fair bit, but still have questions on the vacuum switches.
I have two thermal vacuum switches on the intake. One is for the early fuel evap valve on the exhaust (also called a heat riser valve), and the spark delay switch. This is the big thermal switch that has four ports. The two bottom ones loop through the spark delay valve. That valve is inline to the vac advance on the dizzy. I am not sure when this valve should be open or at what temp. I don't know the original part number. There are a few available.
The other thermal vac switch is two ports and I think it goes to the egr and fuel canisters. I don't know what temp this one should be either.
I put a vac pump on these switches, but they leak, even if I cap the ports that would go to the smog equipment. This doesn't seem right. Will these hold vacuum or do they always loose some? I thought I might be able to use a vac pump to see when the switch opens. I would dip the switch into hot water to test it.
This engine is built as much as possible while still meeting CA smog. I need to get it to pass, but I also need to make sure I can tune it for best performance when needed.
Here are the smog parts:
EGR: when should it be activated for smog specs? Does it really reduce pinging and is it beneficial even when I want to tune for performance and don't care about passing smog?
AIR diverter valve from smog air pump: When should it inject air into the headers? Should it work only at running engine temp and not when the engine is cold? Does it need timed vacuum or manifold vacuum?
Fuel vapor charcoal canisters: same questions as above.
Vacuum Advance is tied to dedicated vac adv port on carb and is ported, so this should be fine for smog.
EFE/heat riser: seems this would go to manifold vac and be routed through a thermal switch so it lets the exhaust flow freely after it warms up. This carb (edelbrock 1400) has two emissions ports on the front and both are closed at an idle. When I crack the throttle, I get a reading on my vac gauge. The one for the dizzy seems like a more smooth increase in vac and the other is more sporadic.
My thought is that if I better understand how these are supposed to work, I will be able to route the lines properly and figure out if the switches are working right or if they need changed. I don't know how many of these emissions parts are used on 49 state trucks. Maybe you Komnifornia brothers will know a bit about this stuff.
Anyone know how lean my idle screws should be to pass smog. I would imagine that too lean will raise some of the emissions and too fat will raise others.
I can post pics of my factory hose diagram, or my carb diagram if needed. I figured I would try to get this stuff working as close to the way the factory intended as possible, since our laws are crap and we also have road side smog checks and smog every year or two for my truck. I would decline to let a road side check run my truck, as they are voluntary, but I don't want to get caught with my pants down. All of the major parts on the truck are 50 state legal, I have just been sliding on the hose routing and they don't make sure some of it works because the truck is hot when it gets tested, and at least the EFE and air cleaner will not be active at that point. A little tweaking gets it to burn clean. I don't have an exhaust gas analyzer or O2 reader to see how clean it burns.
Thanks
. I missed my chance for a good reply but I also didn't want to piss him off. What a ****ing idiot! It wouldn't run if it didn't have a cam installed.
