Removing some smog stuff

[LukeZ]

86 El Camino 305, LG4. I've posted about this before a long time ago.

I don't know if these are the correct terms, but I've been calling it the smog pump. In any event...

There is a belt driven pump with a vacuum tube leading to this other thing, it's the first picture at the top. I'll collectively call them the smog pump system. I want to remove both. Also the line leading to the cat (probably getting a new one soon anyways) and the Air tubes to the exhaust manifold (I'll plug em) will be removed.

The one pump has some wires and vacuum tubes going to and fro. If I remove it, I can simply plug to vacuum tubes.. but what about the electrical stuff? Will my carb and choke be messed up if I unplug it all? Note, I do not want to remove the charcoal canister. That is staying.

It's a weekend and I'm home from the University of Delaware for Thanksgiving break, and I need something to keep me busy. 😛

 

[LukeZ]

And before you say anything. I talked to DMV. It is 100% legal to remove this stuff off of the car, even if it's a daily driver that still has tiny through inspection. They don't care about hardware, just tailpipe emissions.

 

[LukeZ]

Okay so I got this part off. The other part that connects to the other half of the tube that you see will come off next

 

[565bbchevy]

My only concern would be if the catalytic converter needs air from the pump to cool it or to function properly.
My 86' Regal came with the 8 exhaust tubes already plugged off in the manifolds but the air pump was still hooked up so I didn't remove that until I gutted my catalytic and welded it back up along with welding a cap on the tube that comes off the catalytic so exhaust couldn't get out.

 

[LukeZ]

Well, I posted not too long ago about probably getting new exhaust, which includes a new cat. I have a couple appointments with different exhaust places in Delaware next week to get a quote, and from there I'll decide which place is the best bang for buck. Part of the reason I'm removing this is because if I get a new high flow cat or something that doesn't need and air tube, then it doesn't make sense to me to keep this pump. Thanks for bringing that up tho. I will need to buy plugs for my manifolds

 

[jiho]

My only concern would be if the catalytic converter needs air from the pump to cool it or to function properly.

That air fuels combustion of excess HC (hydrocarbons, unburned fuel) and CO (carbon monoxide, partly burned fuel). Disconnecting it will actually cool the cat some. However, there will be more HC and CO out the tailpipe, so it won't be functioning properly.

 

[jiho]

And before you say anything. I talked to DMV. It is 100% legal to remove this stuff off of the car, even if it's a daily driver that still has tiny through inspection. They don't care about hardware, just tailpipe emissions.

What state are you in? I'm in California, and I want to move there. 😀

But seriously -- you'll probably flunk the tailpipe test. The "feedback" carburetor system is not terribly accurate, and really needs the cat to clean up after it, from what I've seen. They generally have to race the motor a couple-three minutes to "condition" the cat (get it up to temp) before it's even got a chance -- and that's if the motor is well tuned. 😱

So that's why they don't care about the hardware -- they'll get you on the emissions!

 

[LukeZ]

What state are you in? I'm in California, and I want to move there. 😀

But seriously -- you'll probably flunk the tailpipe test. The "feedback" carburetor system is not terribly accurate, and really needs the cat to clean up after it, from what I've seen. They generally have to race the motor a couple-three minutes to "condition" the cat (get it up to temp) before it's even got a chance -- and that's if the motor is well tuned. 😱

So that's why they don't care about the hardware -- they'll get you on the emissions!

That's why I'll be getting a new cat, a brand new one. I still have the stock cat from 30 years ago on this car. I think it should pass.

Also, I'm in The First State lol. Yea our emissions arnt terrible but our cars rust to hell over here with all the salt from the ocean and the salt that they throw on the roads in wintertime.

 

[79 USA 1]

If I remember correctly there is a computer connection which routes to the diverter manifold to control the air flow to the air tubes as well as to the cat. Disconnecting that lead should throw a "Check Engine" code which could lead to a failure on emission testing.
I had a 86 El Camino which started life a LG4 305, I upgraded to a 355 out of a 76 Malibu and used all the computer controls from the El Camino with a stock Monte Carlo SS PROM chip.
I also ran full length tube headers modified to accept the AIR injection system, Dual cats and true dual exhaust. Only once was I questioned if the converters were still loaded, cost the shop a set of collector gaskets to break the system to check them.
I really don't think you will see much of a performance gain on a stock LG4 305 by eliminating the AIR pump system.

Just my $.02
Bob S.

 

[LukeZ]

If I remember correctly there is a computer connection which routes to the diverter manifold to control the air flow to the air tubes as well as to the cat. Disconnecting that lead should throw a "Check Engine" code which could lead to a failure on emission testing.
I had a 86 El Camino which started life a LG4 305, I upgraded to a 355 out of a 76 Malibu and used all the computer controls from the El Camino with a stock Monte Carlo SS PROM chip.
I also ran full length tube headers modified to accept the AIR injection system, Dual cats and true dual exhaust. Only once was I questioned if the converters were still loaded, cost the shop a set of collector gaskets to break the system to check them.
I really don't think you will see much of a performance gain on a stock LG4 305 by eliminating the AIR pump system.

Just my $.02
Bob S.

I'm not trying to make a race car out of a 305 lol. I just want to remove some clutter. And as for that check engine code you were referring too... does anyone know where DMV plugs in their computer to the car to check all that stuff? I don't remember them doing it to my car last time I had it inspected, but maybe I missed it.

I have an uncle who is a mechanic, and he might have one of those code checker things I could borrow. I just need to know where it gets plugged into the car at. Thanks