...another one of the "Can't make up my mind" posts.
Background: '85 K5, 350, vortec heads (7 years ago...), Q-Jet, Edelbrock TES headers, AIR injection, EGR pipe (from vortec manifold to O2 sensor port on DS collector). Needs to be compliant w/ AZ emissions, due next August. And they do a visual in addition to the sniffer.
I've had a TBI setup in a box for about a year now. Here are a bunch of random points I think I need to address:
When (If...?) I convert to TBI, I believe I need to retain the smog pump as it was original emissions equipment on the truck. AIR injection with the current headers happens upstream of the O2 sensor port - not sure how that would affect the computer and the fuel metering. Also, AIR injection is currently vacuum-controlled, so I need to find a similar port on the TBI/manifold in order to leave that alone.
Currently, the headers leak. Could be solved by a new gasket on each side, and then installation of an O2 sensor port in the passenger collector (since the driver's side is currently used for EGR.
However, I don't like headers anyway. A manifold from Pace could solve the driver's side issue of EGR + O2 ports; I'd still need a way to connect the smog pump. But that could possibly be done downstream of the O2 sensor port.
Question then remains what to do on the passenger side. A stock-ish manifold with AIR would be one possibility. It would allow me to keep the EFE unit on the passenger side, which is currently present but disabled due to the lack of an exhaust crossover passage in Vortec heads. And it would probably fit with the exhaust Y-pipe, well, sort of.
The current Y-pipe is another issue. It runs below the front driveshaft - which rubs on the Y-pipe when the front axle droops. Not that this is really a problem, it has been like that for a few years now. And the current Y-pipe wants to be close to the DS spring shackle bolt - to the point that it has pushed a nice indentation into the pipe just before the Y. This is despite several attempts to change it. It's not worn through, but...
The thought has occurred that if I go back to manifolds (which means I could actually get at the spark plugs again...) I could use a manifold (with AIR injection...?) that dumps in the center (like this...), and I could have a Y-pipe made to cross over in front of the oil pan sump (?). Not sure how much of a headache that would be, but it would get the Y-pipe away from the front driveshaft. Not sure how I'd fit the EFE unit in there, if only for the visual effect.
I'm aware that it all sounds pretty incoherent; I'm in the planning stages using my current motor. While a entire 5.3/4L65E swap would be certainly be nice, it's too involved with respect to time, space, and resources. Anyways, comments would be appreciated.
Background: '85 K5, 350, vortec heads (7 years ago...), Q-Jet, Edelbrock TES headers, AIR injection, EGR pipe (from vortec manifold to O2 sensor port on DS collector). Needs to be compliant w/ AZ emissions, due next August. And they do a visual in addition to the sniffer.
I've had a TBI setup in a box for about a year now. Here are a bunch of random points I think I need to address:
When (If...?) I convert to TBI, I believe I need to retain the smog pump as it was original emissions equipment on the truck. AIR injection with the current headers happens upstream of the O2 sensor port - not sure how that would affect the computer and the fuel metering. Also, AIR injection is currently vacuum-controlled, so I need to find a similar port on the TBI/manifold in order to leave that alone.
Currently, the headers leak. Could be solved by a new gasket on each side, and then installation of an O2 sensor port in the passenger collector (since the driver's side is currently used for EGR.
However, I don't like headers anyway. A manifold from Pace could solve the driver's side issue of EGR + O2 ports; I'd still need a way to connect the smog pump. But that could possibly be done downstream of the O2 sensor port.
Question then remains what to do on the passenger side. A stock-ish manifold with AIR would be one possibility. It would allow me to keep the EFE unit on the passenger side, which is currently present but disabled due to the lack of an exhaust crossover passage in Vortec heads. And it would probably fit with the exhaust Y-pipe, well, sort of.
The current Y-pipe is another issue. It runs below the front driveshaft - which rubs on the Y-pipe when the front axle droops. Not that this is really a problem, it has been like that for a few years now. And the current Y-pipe wants to be close to the DS spring shackle bolt - to the point that it has pushed a nice indentation into the pipe just before the Y. This is despite several attempts to change it. It's not worn through, but...
The thought has occurred that if I go back to manifolds (which means I could actually get at the spark plugs again...) I could use a manifold (with AIR injection...?) that dumps in the center (like this...), and I could have a Y-pipe made to cross over in front of the oil pan sump (?). Not sure how much of a headache that would be, but it would get the Y-pipe away from the front driveshaft. Not sure how I'd fit the EFE unit in there, if only for the visual effect.
I'm aware that it all sounds pretty incoherent; I'm in the planning stages using my current motor. While a entire 5.3/4L65E swap would be certainly be nice, it's too involved with respect to time, space, and resources. Anyways, comments would be appreciated.
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